2024-03-29T10:01:00Zhttps://minerva.usc.es/oai/requestoai:minerva.usc.es:10347/211322023-07-10T06:18:16Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Ortiz Sanz, Juan Pedro
author
Gil Docampo, María de la Luz
author
Arza García, Marcos
author
Cañas Guerrero, Ignacio
author
2019
Infrared thermography (IRT) techniques for building inspection are currently becoming
increasingly popular as non-destructive methods that provide valuable information about
surface temperature (ST) and ST contrast (delta-T). With the advent of unmanned aerial vehicle
(UAV)-mounted thermal cameras, IRT technology is now endowed with improved flexibility from
an aerial perspective for the study of building envelopes. A case study cellar in Northwest (NW)
Spain is used to assess the capability and reliability of low-altitude passive IRT in evaluating a typical
semi-buried building. The study comparatively assesses the use of a pole-mounted FLIR B335 camera
and a drone-mounted FLIR Vue Pro R camera for this purpose. Both tested IRT systems demonstrate
good e ectiveness in detecting thermal anomalies (e.g., thermal bridges, air leakages, constructive
singularities, and moisture in the walls of the cellar) but pose some di culties in performing accurate
ST measurements under real operating conditions. Working with UAVs gives great flexibility for the
inspection, but the angle of view strongly influences the radiometric data captured and must be taken
into account to avoid disturbances due to specular reflections.
Ortiz-Sanz, J., Gil-Docampo, M., Arza-García, M., & Cañas-Guerrero, I. (2019). IR Thermography from UAVs to Monitor Thermal Anomalies in the Envelopes of Traditional Wine Cellars: Field Test. Remote Sensing, 11(12), 1424.
http://hdl.handle.net/10347/21132
10.3390/rs11121424
2072-4292
Drone
Thermal inspection
Heat leaks
Cellar
Winery
Thermal bridges
Infrared thermography
Wine maturation
UAS
IR Thermography from UAVs to Monitor Thermal Anomalies in the Envelopes of Traditional Wine Cellars: Field Test
oai:minerva.usc.es:10347/262412021-05-22T02:04:59Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956col_10347_10081col_10347_9747
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Marey Pérez, Manuel Francisco
author
Loureiro Veira, Xurxo
author
Corbelle Rico, Eduardo José
author
Fernández Filgueira, Cristina
author
2021
Resilience is not a particularly novel concept, but it has recently become frequently used as a measurement indicator of adaptation capacity under different approaches depending on the field of study. Ideally, for example, forest ecosystems would be resilient to wildfires, one of the most serious types of perturbation they are subjected to. In areas such as the northwest of Spain, a region with one of the most severe records of wildfire occurrence in western Europe, resilience indicators should be related with changes in land planning aimed to minimize the effects of forest fires. This article aimed to analyze the fire resilience strategies of a selected group of forest communities in northwest Spain. More specifically, the perceived risk of wildfires was compared with the actual record of fire events in these communities and the presence or absence of adaptive changes in management practices to reduce risk and improve recovery capacity. A mixed quantitative–qualitative approach was used to gather information about good practices, innovative solutions, and major obstacles for forest fire resilience in Galician common lands. The results suggest that while there is no single form of successful management, a key characteristic of resilient communities is the integration of fire as a management tool
Sustainability 2021, 13(9), 4761; https://doi.org/10.3390/su13094761
http://hdl.handle.net/10347/26241
10.3390/su13094761
2071-1050
Resilience
Forest fires
Common lands
Different Strategies for Resilience to Wildfires: The Experience of Collective Land Ownership in Galicia (Northwest Spain)
oai:minerva.usc.es:10347/225412020-07-06T08:42:02Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956col_10347_10081col_10347_9747
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Corral Rivas, José Javier
author
Vega Nieva, Daniel José
author
Rodríguez Soalleiro, Roque
author
López Sánchez, Carlos Antonio
author
Wehenkel, Christian
author
Vargas Larreta, Benedicto
author
Álvarez González, Juan Gabriel
author
Ruiz González, Ana Daría
author
2017
Accurate quantification of branch volume in trees is important for sustainable forest
management, especially as these fractions are increasingly used for bioenergy, and for precise
forest CO2 quantification. Whereas a large focus has been placed on the compatible estimation
of tree taper and bole volume with and without bark, little effort has been made to develop models
that allow a simultaneous prediction of these variables together with tree branch volume. In this
study, 595 Pinus cooperi trees and 700 Pinus durangensis trees were sampled in pine-oak forests in
the Sierra Madre Occidental, Mexico. A compatible system for predicting two segmented taper
functions, over and under bark; the corresponding merchantable volumes; coarse branch volume
and whole-tree volume was fitted using a modified continuous autoregressive structure to account
for autocorrelation. The proposed compatible equations explained more than 97% of the observed
variability in diameter over and under bark, volume over and under bark, and total tree volume and
more than 64% of the observed variability in branch volume in both species. The method described
can theoretically be replicated for any tree species, thus providing a better understanding of the
patterns of volume distribution by components, potentially improving carbon accounting system and
forest bioenergy planning.
Corral-Rivas, J. J., Vega-Nieva, D. J., Rodríguez-Soalleiro, R., López-Sánchez, C. A., Wehenkel, C., Vargas-Larreta, B., ... & Ruiz-González, A. D. (2017). Compatible system for predicting total and merchantable stem volume over and under bark, branch volume and whole-tree volume of pine species. Forests, 8(11), 417
http://hdl.handle.net/10347/22541
10.3390/f8110417
1999-4907
Taper function
Branch volume
Bark volume
Simultaneous fitting
Compatible System for Predicting Total and Merchantable Stem Volume over and under Bark, Branch Volume and Whole-Tree Volume of Pine Species
oai:minerva.usc.es:10347/162752022-11-14T14:01:44Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250col_10347_10081col_10347_16274
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Osorio Castelao, Lidia
author
Corbelle Rico, Eduardo José
author
Ónega López, Francisco José
author
2014
Este traballo busca caracterizar aos usuarios
potenciais das terras que actualmente se atopan en
situación de abandono ou infrautilización en Galicia. O
sector vacún leiteiro constitúe o núcleo básico do sector
agrario galego polo que coñecer a súa opinión como
demandantes de terra é unha prioridade para poder
establecer un plan de mobilidade de terras. A través da
aplicación dunha variante da metodoloxía Delphi
comprobouse que dende o sector existe un interese por
conseguir máis terra e poder aumentar así a base territorial
das explotacións e, en consecuencia, a súa capacidade
produtiva. A falta de información tanto técnica como
lexislativa relativa aos instrumentos que poden axudar á
mobilización de terras e o seu funcionamento, quedou
presente en moitos dos xuízos emitidos polo panel de
expertos consultados para este traballo, polo que este
constituiría o primeiro paso cara a consecución dunha
mobilidade efectiva de terras
This paper aims to identify potential users for
some of the land currently abandoned in Galicia. We
focused mainly on dairy farmers and cooperatives, as these
constitute today the core of the agricultural sector in the
region and should play a significant role in an eventual plan
for the mobilization of abandoned land. A Delphi expert
panel, formed by technicians working in cooperatives,
showed considerable interest on the part of the dairy farming
sector to increase the amount of land managed and,
therefore, their production capacity. We could also detect a
somewhat worrying lack of knowledge regarding matters
associated to territorial planning and land management
instruments that should be addressed in the first place in a
near future
Osorio Castelao, L., Corbelle Rico, E., & Ónega López, F. (2014). Recuperación e posta en produción de terras abandonadas: a visión do sector vacún leiteiro de Galicia como demandantes no mercado de terras. Recursos Rurais, 10, pp. 7-14. Recuperado de http://www.usc.es/revistas/index.php/rr/article/view/3318
http://hdl.handle.net/10347/16275
2255-5994
Abandono de terras
Cooperativas agrarias
Método Delphi
Mobilidade de terras
Delphi method
Farmer cooperatives
Land abandonment
Land mobility
Recuperación e posta en produción de terras abandonadas: a visión do sector vacún leiteiro de Galicia como demandantes no mercado de terras
oai:minerva.usc.es:10347/277502022-11-17T14:00:39Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Fouz Varela, David Mateo
author
Carballo Sánchez, Rodrigo
author
López Moreira, Iván
author
Iglesias Rodríguez, Gregorio
author
2022
The tidal and river in-stream energy resource in the Shannon Estuary (W Ireland) is investigated using of high-resolution numerical modelling and spatial analysis. Although freshwater discharges are large, their influence on the available resource is found to be all but negligible, the tide being the main driver of estuarine circulation. The Tidal Stream Exploitability (TSE) index is adapted to the analysis of estuaries with non-depth-limited areas (TSEndl), such as the Shannon Estuary, and then used to select the hotspots with potential for a tidal stream farm. For this purpose, a new depth penalty-limiting function is defined to avoid overestimating the available energy potential in areas with depths greater than those required for tidal energy converter operation. Seven hotspots are identified based on the revised index. The approach followed in this study illustrates the applicability of high-resolution numerical modelling and spatial analysis for identifying the most appropriate areas for tidal stream energy conversion. Finally, the potential of tidal stream energy to contribute to the much-needed decarbonisation of the energy mix in Ireland is emphasized
Renewable Energy 185 (2022) 61-74. https://doi.org/10.1016/j.renene.2021.12.055
http://hdl.handle.net/10347/27750
10.1016/j.renene.2021.12.055
0960-1481
Tidal stream energy
River in-stream energy
Non-depth-limited areas
Numerical modelling
Resource assessment
Tidal stream energy potential in the Shannon Estuary
oai:minerva.usc.es:10347/322542024-02-03T01:02:59Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Carral, Luis
author
Rodríguez-Guerreiro, Mª Jesús
author
Vargas, Andreina
author
Álvarez-Feal, Carlos
author
Carballo, Rodrigo
author
Lamas Galdo, María Isabel
author
López, Iván
author
2021
For the evolution and development of artificial reefs to attain the expected results, hydrodynamics is emerging as a key factor that must be taken analyzed in detail. In particular, thanks to the hydrodynamics of a given coastal area, suitable water circulation and velocity in the reef's interior can increase the yield and the renewal of nutrients favourable for larval settlement, along with reducing the sedimentation.
This document proposes a methodology for determining the geometry of an artificial reef group adapted to the specific characteristics of the selected zone of installation, the Ría de Ares-Betanzos (NW Spain), based on hydrodynamic criteria by defining the Artificial Reef Tool (ART). The starting point of the ART tool is the existing reef model or AR unit's design –a modular construction with productive and protective features. Then a high-resolution hydrodynamic circulation model (HCM) is developed allowing the high-resolution site-specific computation of the flow pattern in the selected area. Finally, the results obtained are used as input for a hydrodynamic model for food delivery prediction (HMFDP), allowing the estimation of the food supply to each module. The results obtained lead to the definition of the geometry of the reef group.
Luis Carral, María Isabel Lamas–Galdo, Mª Jesús Rodríguez-Guerreiro, Andreina Vargas, Carlos Álvarez-Feal, Iván López, Rodrigo Carballo, Configuration methodology for a green variety reef system (AR group) based on hydrodynamic criteria – Application to the Ría de Ares-Betanzos, Estuarine, Coastal and Shelf Science, Volume 252, 2021, 107301, ISSN 0272-7714, https://doi.org/10.1016/j.ecss.2021.107301.
0272-7714
1096-0015
http://hdl.handle.net/10347/32254
10.1016/j.ecss.2021.107301
Artificial reef
Hydrodynamics
Coastal dynamics
Computational fluid dynamics (CFD)
Configuration methodology for a green variety reef system (AR group) based on hydrodynamic criteria - Application to the Ria de Ares-Betanzos
oai:minerva.usc.es:10347/224022022-11-22T12:47:41Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956col_10347_10081col_10347_9747
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Magdon, Paul
author
González Ferreiro, Eduardo Manuel
author
Pérez Cruzado, César
author
Purnama, Edwine Setia
author
Sarodja, Damayanti
author
Kleinn, Christoph
author
2018
Estimates of aboveground biomass (AGB) in forests are critically required by many actors including forest managers, forest services and policy makers. Because the AGB of a forest cannot be observed directly, models need to be employed. Allometric models that predict the AGB of a single tree as a function of diameter at breast height (DBH) are commonly used in forest inventories that use a probability selection scheme to estimate total AGB. However, for forest areas with limited accessibility, implementing such a field-based survey can be challenging. In such cases, models that use remotely sensed information may support the biomass assessment if useful predictor variables are available and statistically sound estimators can be derived. Airborne laser scanning (ALS) has become a prominent auxiliary data source for forest biomass assessments and is even considered to be one of the most promising technologies for AGB assessments in forests. In this study, we combined ALS and forest inventory data from a logged-over tropical peat swamp forest in Central Kalimantan, Indonesia to estimate total AGB. Our objective was to compare the precision of AGB estimates from two approaches: (i) from a field-based inventory only and, (ii) from an ALS-assisted approach where ALS and field inventory data were combined. We were particularly interested in analyzing whether the precision of AGB estimates can be improved by integrating ALS data under the particular conditions. For the inventory, we used a standard approach based on a systematic square sample grid. For building a biomass-link model that relates the field based AGB estimates to ALS derived metrics, we used a parametric nonlinear model. From the field-based approach, the estimated mean AGB was 241.38 Mgha −1 with a standard error of 11.17 Mgha −1 (SE% = 4.63%). Using the ALS-assisted approach, we estimated a similar mean AGB of 245.08 Mgha −1 with a slightly smaller standard error of 10.57 Mgha −1 (SE% = 4.30%). Altogether, this is an improvement of precision of estimation, even though the biomass-link model we found showed a large Root Mean Square Error (RMSE) of 47.43 Mgha −1 . We conclude that ALS data can support the estimation of AGB in logged-over tropical peat swamp forests even if the model quality is relatively low. A modest increase in precision of estimation (from 4.6% to 4.3%), as we found it in our study area, will be welcomed by all forest inventory planners as long as ALS data and analysis expertise are available at low or no cost. Otherwise, it gives rise to a challenging economic question, namely whether the cost of the acquisition of ALS data is reasonable in light of the actual increase in precision
Magdon, P.; González-Ferreiro, E.; Pérez-Cruzado, C.; Purnama, E.S.; Sarodja, D.; Kleinn, C. Evaluating the Potential of ALS Data to Increase the Efficiency of Aboveground Biomass Estimates in Tropical Peat–Swamp Forests. Remote Sens. 2018, 10, 1344
http://hdl.handle.net/10347/22402
10.3390/rs10091344
2072-4292
Model-assisted
Forest inventory
Biomass
Evaluating the potential of ALS data to increase the efficiency of aboveground biomass estimates in tropical peat–swamp forests
oai:minerva.usc.es:10347/235332021-08-09T07:36:22Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Mirás Avalos, José Manuel
author
Ramírez Cuesta, Juan M.
author
Fandiño Beiro, María
author
Cancela Barrio, Javier José
author
Intrigliolo, Diego S.
author
2020
Water erosion is a severe threat to soil resources, especially on cultivated lands, such as vineyards, which are extremely susceptible to soil losses. In this context, management practices aiming at reducing erosion risks must be favored. This current study aimed at estimating soil losses in two vineyards under Atlantic climatic conditions (Galicia, North West Spain). The capacity of two management practices for reducing soil erosion was tested and compared with tilled soil in the inter-rows: (i) application of mulching, and (ii) maintaining native vegetation. Soil losses were assessed using erosion pins and micro-plots. In addition, the improved stock unearthing method (ISUM) was employed in one of the vineyards to estimate soil remobilization since plantation. Soil loss rates in one of the vineyards were lower when soil was managed under mulching (0.36 Mg ha−1) and native vegetation (0.42 Mg ha−1), compared to tilled soil (0.84 Mg ha−1). Sediment losses measured in the second vineyard ranged between 0.21 and 0.69 Mg ha−1, depending on the treatment, but no clear conclusions could be drawn. Long-term soil loss, as estimated by ISUM, was of the same order of magnitude than that obtained by erosion pins and micro-plots. In both vineyards, soil loss rates were lower than those registered in Mediterranean vineyards, and were below the limit for sustainable erosion in Europe. Nevertheless, soil management practices alternative to tillage in the inter-row might reduce erosion risks under Atlantic climate conditions
Mirás-Avalos, J.M.; Ramírez-Cuesta, J.M.; Fandiño, M.; Cancela, J.J.; Intrigliolo, D.S. Agronomic Practices for Reducing Soil Erosion in Hillside Vineyards under Atlantic Climatic Conditions (Galicia, Spain). Soil Syst. 2020, 4, 19
http://hdl.handle.net/10347/23533
10.3390/soilsystems4020019
2571-8789
Cover crops
Mulching
Runoff
Soil erosion assessment
Sustainability
Temperate climate
Vineyards
Vitis vinifera
Agronomic Practices for Reducing Soil Erosion in Hillside Vineyards under Atlantic Climatic Conditions (Galicia, Spain)
oai:minerva.usc.es:10347/223422020-05-16T02:01:45Zcom_10347_2916com_10347_2891com_10347_2888com_10347_227com_10347_2954com_10347_2893col_10347_12324col_10347_10081
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López Serrano, Pablito Marcelo
author
López Sánchez, Carlos Antonio
author
Díaz Varela, Ramón Alberto
author
Corral Rivas, José Javier
author
Solís Moreno, Raúl
author
Vargas Larreta, Benedicto
author
Álvarez González, Juan Gabriel
author
2015
The Sierra Madre Occidental mountain range (Durango, Mexico) is of great ecological interest because of the high degree of environmental heterogeneity in
the area. The objective of the present study was to estimate the biomass of
mixed and uneven-aged forests in the Sierra Madre Occidental by using Landsat-5 TM spectral data and forest inventory data. We used the ATCOR3 ® atmospheric and topographic correction module to convert remotely sensed imagery digital signals to surface reflectance values. The usual approach of modeling stand variables by using multiple linear regression was compared with a
hybrid model developed in two steps: in the first step a regression tree was
used to obtain an initial classification of homogeneous biomass groups, and
multiple linear regression models were then fitted to each node of the pruned
regression tree. Cross-validation of the hybrid model explained 72.96% of the
observed stand biomass variation, with a reduction in the RMSE of 25.47% with
respect to the estimates yielded by the linear model fitted to the complete
database. The most important variables for the binary classification process in
the regression tree were the albedo, the corrected readings of the short-wave
infrared band of the satellite (2.08-2.35 µm) and the topographic moisture
index. We used the model output to construct a map for estimating biomass in
the study area, which yielded values of between 51 and 235 Mg ha-1. The use
of regression trees in combination with stepwise regression of corrected satellite imagery proved a reliable method for estimating forest biomass.
López-Serrano PM, López-Sánchez CA, Díaz-Varela RA, Corral-Rivas JJ, Solís-Moreno R, Vargas-Larreta B, Álvarez-González JG (2015). Estimating biomass of mixed and uneven-aged forests using spectral data and a hybrid model combining regression trees and linear models. iForest 9: 226-234. - doi: 10.3832/ifor1504-008
http://hdl.handle.net/10347/22342
10.3832/ifor1504-008
1971-7458
Regression trees
Stepwise regression
Remote sensing
ATCOR3
Terrain features
Image texture
Estimating biomass of mixed and uneven-aged forests using spectral data and a hybrid model combining regression trees and linear models
oai:minerva.usc.es:10347/162852022-11-15T13:37:25Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250col_10347_10081col_10347_16280
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Gorgoso Varela, José Javier
author
López Fernández, Celia
author
Rojo Alboreca, Alberto
author
Cruz Cobos, Francisco
author
2015
The Mexican Management Method for Unevenaged
Forests or MMOBI (from the Spanish Método
Mexicano de Ordenación de Bosques Irregulares) is the
continuous cover forestry management system usually used
in the state of Durango (Mexico). The silviculture system
applied in the MMOBI is based on selective logging aimed at
yielding a reverse “J-shaped” distribution.
The objective of the present study was to analyze the
application of the MMOBI to natural mixed stands in Asturias
(northern Spain). These stands are represented in strata
numbers 4 and 9, defined in the third Spanish National
Forest Survey, composed mainly of deciduous hardwoods.
The observed diameter distributions and the ideal diameter
distributions obtained by the MMOBI for each genus were
estimated. The percentage of felling intensity (IC%) was
generally low in stratum 4, and was less than 20% for most
genera except Fraxinus and Acer, for which IC > 50%. In
stratum 9, IC% was generally higher than in stratum 4,
although also low to intermediate, except for the genus Tilia
(IC > 50%), whose trees are part of what commonly called
Green Tree Retention.
The MMOBI is presented as an alternative forest
management method in protective stands in this region
El Método Mexicano de Ordenación de Bosques
Irregulares (MMOBI) es el sistema de gestión forestal de
cubierta forestal continua empleado habitualmente en el
estado de Durango (México). La selvicultura que se aplica
en el MMOBI consiste en cortas de selección individual (o
entresaca árbol a árbol), buscando una distribución
diamétrica en forma de J invertida.
En este trabajo se analiza la aplicación del MMOBI en las
masas naturales mixtas de Asturias (norte de España)
representadas en los estratos números 4 y 9 del Tercer
Inventario Forestal Nacional, formados mayoritariamente
por frondosas caducifolias.
Se ha calculado para cada género la distribución diamétrica
real y se ha estimado la ideal según el MMOBI. El
porcentaje de intensidad de corta (IC%) fue generalmente
bajo en el estrato 4, siendo inferior al 20% en la mayoría de
los géneros excepto en Fraxinus y Acer con IC >50%. En el
estrato 9 la IC% fue generalmente más alta que en el estrato
4, aunque también fue de baja a intermedia, excepto para el
género Tilia con IC >50%, cuyos árboles se suelen incluir en
el Green Tree Retention.
El MMOBI se presenta como una alternativa de gestión para
masas con un carácter preferente protector
Gorgoso-Varela, J., López-Fernández, C., Rojo-Alboreca, A., & Cruz-Cobos, F. (2015). Application of Mexican Management Method for Unevenaged Forests (MMOBI) to natural mixed stands in Asturias (northern Spain). Recursos Rurais, 11, pp. 61-71. Recuperado de http://www.usc.es/revistas/index.php/rr/article/view/3333
http://hdl.handle.net/10347/16285
2255-5994
Forest management
Natural mixed stands
Deciduous hardwoods
De Liocourt
Green Tree Retention
Gestión forestal
Masas naturales
Frondosas autóctonas
De Liocourt
Green Tree Retention
Application of Mexican Management Method for Unevenaged Forests (MMOBI) to natural mixed stands in Asturias (northern Spain)
oai:minerva.usc.es:10347/215922020-09-07T11:43:16Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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González Ferreiro, Eduardo Manuel
author
Miranda Barrós, David
author
Barreiro Fernández, L.
author
Buján Seoane, Sandra
author
García Gutiérrez, Jorge
author
Diéguez Aranda, Ulises
author
2013
Aims of study: To evaluate the potential use of canopy height and intensity distributions, determined by airborne LiDAR, for the estimation of crown, stem and aboveground biomass fractions
To assess the effects of a reduction in LiDAR pulse densities on model precision
Area of study: The study area is located in Galicia, NW Spain. The forests are representative of Eucalyptus globules stands in NW Spain, characterized by low-intensity silvicultural treatments and by the presence of tall shrub
Material and methods: Linear, multiplicative power and exponential models were used to establish empirical relationships between field measurements and LiDAR metrics
A random selection of LiDAR returns and a comparison of the prediction errors by LiDAR pulse density factor were performed to study a possible loss of fit in these models
Main results: Models showed similar goodness-of-fit statistics to those reported in the international literature. R2 ranged from 0.52 to 0.75 for stand crown biomass, from 0.64 to 0.87 for stand stem biomass, and from 0.63 to 0.86 for stand aboveground biomass. The RMSE/MEAN · 100 of the set of fitted models ranged from 17.4% to 28.4%
Models precision was essentially maintained when 87.5% of the original point cloud was reduced, i.e. a reduction from 4 pulses m–2 to 0.5 pulses m–2
Research highlights: Considering the results of this study, the low-density LiDAR data that are released by the Spanish National Geographic Institute will be an excellent source of information for reducing the cost of forest inventories
Gonzalez-Ferreiro, E. et al.(2013). Modelling stand biomass fractions in Galician Eucalyptus globulus plantations by use of different LiDAR pulse densities. "Forest Systems", vol. 22, n. 3 p.510-525
2171-5068
http://hdl.handle.net/10347/21592
10.5424/fs/2013223-03878
2171-9845
Eucalypt plantations
Airborne laser scanning
Aboveground biomass
Carbon stocks
Remote sensing
Forest inventory
Modelling stand biomass fractions in Galician Eucalyptus globulus plantations by use of different LiDAR pulse densities
oai:minerva.usc.es:10347/178892022-02-11T11:24:30Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Gil Docampo, María de la Luz
author
Ortiz Sanz, Juan Pedro
author
Martínez-Rodriguez, Santiago
author
Marcos-Robles, José Luis
author
Arza-García, Marcos
author
Sánchez-Sastre, Luis Fernando
author
2018-10-02
Water supply devices enable afforestation in dry climates and on poor lands with generally
high success rates. Previous survival analyses have been based on the direct observation of
each individual plant in the field, which entails considerable effort and costs. This study
provides a low-cost method to discriminate between live and dead plants in afforestations
that can efficiently replace traditional field inspections through the use of UAVs equipped
with RGB and NIR sensors. The method combines the use of a conventional camera with an
identical camera modified to record the NIR channel. Survival analysis was performed with
digital image processing techniques based on calculated indices associated with plant vigour
and PCA-based decorrelation. The method yielded results with high global accuracy rates
(~96.2%) with a minimum percentage of doubtful plants, even in young plantations
(seedlings < 30 cm tall). The procedure could be particularly useful in hazardous areas
M. L. Gil-Docampo, J. Ortiz-Sanz, S. Martínez-Rodríguez, J. L. Marcos-Robles, M. Arza-García & L. F. Sánchez-Sastre (2018) Plant survival monitoring with UAVs and multispectral data in difficult access afforested areas, Geocarto International, DOI: 10.1080/10106049.2018.1508312
1010-6049
http://hdl.handle.net/10347/17889
10.1080/10106049.2018.1508312
UAV
Plant control
Degraded region
Gap detection
Waterboxx
Plant survival monitoring with UAVs and multispectral data in difficult access afforested areas
oai:minerva.usc.es:10347/218322020-05-18T18:51:04Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Castro Ramos, Ángel
author
Pereira González, José Manuel
author
Amiama Ares, Carlos
author
Bueno Lema, Javier
author
2015
The aim of this study was to determine the characteristics of the dairy farms that installed an automatic milking system (AMS). A survey of 38 dairy farms with AMS, in Galicia (Spain), collected information on quantitative and qualitative variables. Following elimination of redundant variables, categorical principal component analysis identified 4 factors accounting for 43.7% of the total variance. Using these factors, the farms studied were subjected to hierarchical cluster analysis which differentiated 4 types of farms: (A) farms with more leisure and quality of life where the AMS covered the expectations of farmers (29%); (B) farms that removed cows more often due to AMS and farmers with more stress (34%); (C) farms with little leisure and farmers with no successor (21%); (D) large farms with many fulltime employees (FTE) where the AMS had covered farmer’s expectations the least (11%). Generally the farms were based on a family structure with a high percentage of FTE. With the adoption of AMS these farms sought to increase milk production, save labour and have more flexibility. With 87% of farms with free cow traffic the activity that took the most of the farmer’s time was fetching cows for milking (1 h/day). Nearly 58% of farmers were completely satisfied with their AMS, although this value reached 91% in farms with herd sizes below the average which were better adapted to the use of one AMS.
Ángel Castro, José M. Pereira, Carlos Amiama and Javier Bueno (2015). Typologies of Dairy Farms with Automatic Milking System in Northwest Spain and Farmers’ Satisfaction, Italian Journal of Animal Science, 14:2, 3559, DOI: 10.4081/ijas.2015.3559
1594-4077
http://hdl.handle.net/10347/21832
10.4081/ijas.2015.3559
1828-051X
Automatic milking system
Farm structure
Farm typology
Farmer satisfaction
Typologies of Dairy Farms with Automatic Milking System in Northwest Spain and Farmers’ Satisfaction
oai:minerva.usc.es:10347/290852022-11-14T13:34:46Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Ortiz Sanz, Juan Pedro
author
Gil Docampo, María de la Luz
author
Bastos Costas, Guillermo
author
2022
Gridshells are unexploited structures, over which lengths measurement are difficult to do due to their size and complex curvature. To deformation measurement on a timber gridshell beam and on an entire gridshell, we used an affordable photogrammetry system that consisted of a consumer-level camera, a tripod, a mast with a gimbal to elevate the camera, a laptop, and two photogrammetric software: PhotoModeler Scanner and Metashape. The beam was subjected to a bending test, and the gridshell was loaded with 105 kg of dead load per node on its five central nodes. The maximum error in the measurement was 1.26 mm on the beam and 3.45 mm on the gridshell, which corresponded to 0.77 ‰ error relative to the span of the beam and 0.41 ‰ relative to the length of the gridshell. Three-dimensional models obtained through the proposed method serve as dimensional data with a uniform error around the object
Measurement 198 (2022) 111365
http://hdl.handle.net/10347/29085
10.1016/j.measurement.2022.111365
0263-2241
Gridshell
Photogrammetry
Timber
Metric quality
3D model
Inexpensive photogrammetry applied to displacement measurement of a gridshell
oai:minerva.usc.es:10347/178422023-07-10T06:17:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_9747col_10347_15615
00925njm 22002777a 4500
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Rodríguez Soalleiro, Roque
author
Eimil Fraga, Cristina
author
Gómez García, Esteban
author
García Villabrille, Juan Daniel
author
Rojo Alboreca, Alberto
author
Muñoz, Fernando
author
Oliveira Rodríguez, Nerea de
author
Sixto, Hortensia
author
Pérez Cruzado, César
author
2018-11-05
Background: Coupling biomass models with nutrient concentrations can provide sound estimations of carbon and nutrient contents, enabling the improvement of carbon and
nutrient balance in forest ecosystems. Although nutrient concentrations are often assumed to be constant for some species and specific tree components, at least in mature stands, the concentrations usually vary with age, site index and even with tree density.The main objective of this study was to evaluate the sources of variation in nutrient concentrations in biomass compartments usually removed during harvesting operations, covering a range of species and management conditions: semi-natural forest, conventional forest plantations and short rotation forestry (SRF). Five species (Betula pubescens, Quercus robur, Eucalyptus globulus, Eucalyptus nitens and Populus spp.) and 14 genotypes were considered. A total of 430 trees were sampled in 61 plots to obtain 6 biomass components: leaves, twigs, thin branches, thick branches, bark and wood. Aboveground leafless biomass was pooled together for poplar. The concentrations of C, N, K, P, Ca, Mg, S, Fe, Mn, Cu, Zn and B were measured and the total biomass of each sampled tree and plot were determined. The data were analysed using boosted regression trees and conventional techniques.
Results: The main sources of variation in nutrient concentrations were biomass component >> genotype (species) ≈ age > tree diameter. The concentrations of Ca, Mg and K were most strongly affected by genotype and age. The concentrations of P, K, Ca, Mg, S and Cu in the wood component decreased with age, whereas C concentrations increased, with a trend to reach 50% in the older trees. In the SRF, interamerican poplar and P. trichocarpa
genotypes were comparatively more efficient in terms of Ca and K nutrient assimilation index (NAI) (+ 65 – 85%) than eucalypts, mainly because leafless biomass can be removed. In the conventional eucalypt plantations (rotation 15 years), debarking the wood at logging (savings of 225% of Ca and 254% of Mg for E. globulus) or the use of selected genotypes (savings of 45% of P and 35% of Ca) will provide wood at a relatively lower nutrient cost. Considering all the E. globulus genotypes together, the management for pulp with removal of debarked wood shows NAI values well above (× 1.7 – × 3.9) the ones found for poplar or eucalypt SRF and also higher (× 1.6 – × 4.0) than the ones found for oak and birch managed in medium or long rotations. The annual rates of nutrient removal were low in the native broadleaved species but the rates of available soil nutrients removed were high as compared to poplar or eucalypts. Management of native broadleaved species should consider nutrient stability through selection of the biomass compartments removed.
Conclusions: The nutrient assimilation index is higher in poplar grown under short rotation
forestry management than in the other systems considered. Nutrient management of fast growing eucalyptus plantations could be improved by selecting efficient genotypes and limiting removal of wood. The values of the nutrient assimilation index are lower in the
natural stands of native broadleaved species than in the other systems considered
Rodríguez-Soalleiro R., Eimil-Fraga C., Gómez-García E., García-Villabrille J.D., Rojo-Alboreca A., Muñoz F., Oliveira N., Sixto H., Pérez-Cruzado C. 2018. Exploring the factors affecting carbon and nutrient concentrations in tree biomass components in natural forests, forest plantations and short rotation forestry. Forest Ecosystems 5: 35
2197-5620
http://hdl.handle.net/10347/17842
10.1186/s40663-018-0154-y
Nutrient removal
Biomass crops
Poplar genotypes
Eucalyptus
Oak
Birch
Plantation sustainability
Exploring the factors affecting carbon and nutrient concentrations in tree biomass components in natural forests, forest plantations and short rotation forestry
oai:minerva.usc.es:10347/176132022-11-23T11:54:13Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
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Rojo Alboreca, Alberto
author
García Villabrille, Juan Daniel
author
Corral-Rivas, José Javier
author
Alía, Ricardo
author
Montero González, Gregorio
author
2017
Aim of study: To propose a new approach to defining rotation ages on the basis of productive and technological aspects and to present an example of application of the methodology to natural Pinus sylvestris stands in relation to silvicultural treatment (light or heavy thinning) and site index.
Area of study: Central Spain.
Material and methods: We assumed that the price per m3 of logwood suitable for veneer is four times higher than logwood not apt for veneer. Considering the yield distribution for different technological and commercial classes, a model of diameter distributions and yield tables, the variation in an average price index for different age classes, site indexes and silvicultural treatments was calculated. The age at which the price index rises by less than 3%, the proportion of trees with d.b.h. higher than 40 cm, and other aspects such as the possible presence of fungal decay in old-growth stands were also taken into account to establish three criteria for defining rotation ages.
Main results: The proposed methodology generates a wide range of rotation ages between 100 and 140 years for lightly thinned stands, and between 90 and 140 years for heavily thinned stands, depending on the site index.
Research highlights: The proposed approach is based on technological and productive criteria, with the limitations imposed by sanitary risks. The methodology can be applied to generate rotation ages in relation to different site indexes and silvicultural treatments, provided that the timber market prices and the yield distribution for different technological and commercial classes are known, and that a model of diameter distributions and yield tables are available.
Rojo-Alboreca, A., García-Villabrille, J., Corral-Rivas, J., Alía, R., & Montero, G. (2017). A new approach to defining rotation ages on the basis of productive and technological aspects. Application to natural Pinus sylvestris L. stands in Central Spain. Forest Systems, 26(2), e03S. doi:http://dx.doi.org/10.5424/fs/2017262-10628
2171-5068
http://hdl.handle.net/10347/17613
10.5424/fs/2017262-10628
2171-9845
Scots pine
Price index
Veneer timber
Yield tables
Diameter distributions
A new approach to defining rotation ages on the basis of productive and technological aspects. Application to natural Pinus sylvestris L. stands in Central Spain
oai:minerva.usc.es:10347/220422020-05-06T02:01:43Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Gómez García, Esteban
author
2013
En este estudio se describe la metodología para desarrollar un modelo dinámico de crecimiento para rodales regulares y su desagregación para predecir volúmenes según destinos comerciales y la biomasa de árboles individuales (total o por componentes). Como ejemplo se toman los modelos desarrollados para rodales regulares de Betula pubescens Ehrh. y Quercus robur L. en Galicia (noroeste de España). La condición de un rodal se describe por las variables de estado; altura dominante, número de árboles por hectárea y área basal. El desarrollo de funciones de transición en diferencias algebraicas permite proyectar dichas variables a cualquier instante futuro. Un sistema de desagregación permite estimar, a partir de las variables de estado, el número de árboles y la altura media por clase diamétrica. Por último, el volumen y la biomasa se estiman desarrollando funciones de salida, que utilizan los diámetros y alturas estimadas en el proceso de desagregación
This study presents a methodological process that can be used to develop disaggregated dynamic growth models for estimating total and merchantable volume and aboveground tree biomass (total or by tree component) for single species in even-aged stands. An example for birch (Betula pubescens Ehrh.) and pedunculate oak (Quercus robur L.) stands in Galicia (northwestern Spain) is used. The stand state at any point in time is defined by three static variables: dominant height, number of trees per hectare and stand basal area. These variables are projected using transition functions in algebraic difference form. A disaggregation system allows estimation of the number of trees and the average height per diameter class from state variables. Finally, output functions that use the estimated diameters and heights are used to estimate volume and biomass
Gómez-García, Esteban. (2013). Modelos dinámicos de crecimiento para rodales regulares y su desagregación para la estimación de volúmenes y biomasa. Revista Chapingo serie ciencias forestales y del ambiente, 19(3), 337-350. https://dx.doi.org/10.5154/r.rchscfa.2012.08.047
2007-3828
http://hdl.handle.net/10347/22042
10.5154/r.rchscfa.2012.08.047
2007-4018
Betula pubescens Ehrh.
Quercus robur L.
Sistema de desagregación
Galicia
España
Disaggregation system
Spain
Modelos dinámicos de crecimiento para rodales regulares y su desagregación para la estimación de volúmenes y biomasa
oai:minerva.usc.es:10347/218262020-04-28T02:02:15Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Raposo González, Juan Ramón
author
Molinero, J.
author
Dafonte Dafonte, Jorge
author
2012
Quantifying groundwater recharge in crystalline rocks presents great difficulties due to the high heterogeneity of the underground medium (mainly, due to heterogeneity in fracture network, which determines hydraulic parameters of the bedrock like hydraulic conductivity or effective porosity). Traditionally these rocks have been considered to have very low permeability, and their groundwater resources have usually been neglected; however, they can be of local importance when the bedrock presents a net of well-developed fractures. The current European Water Framework Directive requires an efficient management of all groundwater resources; this begins with a proper knowledge of the aquifer and accurate recharge estimation. In this study, an assessment of groundwater resources in the Spanish hydrologic district of Galicia-Costa, dominated by granitic and metasedimentary rocks, was carried out. A water-balance modeling approach was used for estimating recharge rates in nine pilot catchments representatives of both geologic materials. These results were cross-validated with an independent technique, i.e. the chloride mass balance (CMB). A relation among groundwater recharge and annual precipitation according to two different logistic curves was found for both granites and metasedimentary rocks, thus allowing the parameterization of recharge by means of only a few hydrogeological parameters. Total groundwater resources in Galicia-Costa were estimated to be 4427 hm3 yr−1. An analysis of spatial and temporal variability of recharge was also carried out.
Raposo, J. R., Molinero, J., and Dafonte, J.: Parameterization and quantification of recharge in crystalline fractured bedrocks in Galicia-Costa (NW Spain), Hydrol. Earth Syst. Sci., 16, 1667–1683, https://doi.org/10.5194/hess-16-1667-2012, 2012.
1027-5606
http://hdl.handle.net/10347/21826
10.5194/hess-16-1667-2012
1607-7938
Parameterization
Quantification
Crystalline
Galicia-Costa
Underground medium
Chloride mass balance (CMB)
Parameterization and quantification of recharge in crystalline fractured bedrocks in Galicia-Costa (NW Spain)
oai:minerva.usc.es:10347/322602024-02-03T01:03:26Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Carballo, Rodrigo
author
López, Iván
author
Iglesias, Gregorio
author
2020
The intra-annual variability in the wave resource is often disregarded when analysing the performance of wave energy converters (WECs), despite the fact that this variability is substantial in the majority of the areas of interest for the development of wave energy. The objective of this work is to analyse and quantify the intra-annual variability in the performance of oscillating water column (OWC) WECs through a case study in Galicia (NW Spain). To this end a three-step methodology which combines numerical and experimental modelling is followed: (i) intra-annual wave energy resource matrices are determined numerically through a high-resolution procedure; (ii) efficiency matrices of the device are determined by means of physical modelling, considering the influence of air compressibility and different turbine specifications represented through different values of turbine-induced damping; and (iii) finally, intra-annual energy capture matrices are calculated by combining the resource and efficiency matrices. It is found that the intra-annual variability in the energy capture of an OWC converter is significant, over 20% in the case study considered, albeit slightly smaller than that of the wave energy resource itself. The turbine-induced damping exerts a modulating effect over the variability in the intra-annual captured energy. Furthermore, the optimum damping which maximises the performance of the OWC converter varies from month to month.
I. López, R. Carballo, G. Iglesias, Intra-annual variability in the performance of an oscillating water column wave energy converter, Energy Conversion and Management, Volume 207, 2020, 112536, ISSN 0196-8904, https://doi.org/10.1016/j.enconman.2020.112536.
0196-8904
http://hdl.handle.net/10347/32260
10.1016/j.enconman.2020.112536
Oscillating water column
Physical modelling
Air compressibility
Numerical modelling
Wave energy
Turbine-induced damping
Intra-annual variability in the performance of an oscillating water column wave energy converter
oai:minerva.usc.es:10347/226942020-05-30T02:00:59Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Riesco Muñoz, Guillermo
author
Díaz González, J.
author
2007
Se estudió la densidad, contracción, higroscopicidad y punto de saturación de la pared celular en la madera de ejemplares jóvenes de tres especies importantes en la producción maderera española: Pinus pinaster, Pinus sylvestris y Pinus radiata. Se muestrearon 29 pinos procedentes de raleos efectuados en diferentes masas forestales de Galicia (noroeste de España). El material de ensayo fueron probetas de pequeñas dimensiones sin defectos. La madera de Pinus pinaster resultó semipesada y más inestable en dimensiones ante los cambios de humedad que las de Pinus radiata y Pinus sylvestris, que resultaron ligeras y relativamente estables, especialmente Pinus radiata. La densidad en Pinus pinaster fue similar a la obtenida en estudios anteriores sobre pies adultos. Pinus radiata y Pinus sylvestris presentaron madera más ligera que la de pies adultos. Las propiedades relativas a la estabilidad dimensional fueron similares en la madera joven analizada y en la madera de pies adultos, a excepción de la madera de Pinus radiata, que resultó más estable en la muestra que en la madera adulta. La variación entre zonas del fuste y entre individuos fue notable para las variables densidad y peso específico, aun en el caso de árboles muestreados en un mismo rodal y estación.
Wood density, shrinkage, hygroscopicity and fibre saturation point were studied in young trees corresponding to three important species in the spanish timber production (Pinus pinaster, Pinus sylvestris and Pinus radiata). Twenty-nine thinned pines from different stands of Galicia (northwestern Spain) were sampled. The test material was small size defect-free specimens. The wood of Pinus pinaster exhibited intermediate density and more instability in dimensions, due to environmental moisture changes, than wood of Pinus radiata and Pinus sylvestris. These woods were light and relatively stable, especially Pinus radiata. The density in Pinus pinaster was similar to that obtained in previous studies on adult trees. Pinus radiata and Pinus sylvestris showed lower density than adult trees. The shrinkage properties were similar in the analyzed young wood and in the wood of adult trees, excepting the wood sampled for Pinus radiata, more stable than adult wood. Even with a sample of trees from the same stand in a specific site, there were significant differences in wood density among positions in each tree and among trees.
Riesco Muñoz, G., & Díaz González, J. (2007). Características físicas de la madera de pino procedente de raleos en el noroeste de España. Maderas. Ciencia y tecnología, 9(3), 233-244.
http://hdl.handle.net/10347/22694
0718-221X
Pinus
Propiedades físicas de la madera
Clara
Raleo
Galicia
Pinus
Physical properties of wood
Thinning
Galicia
Características físicas de la madera de pino procedente de raleos en el noroeste de España
oai:minerva.usc.es:10347/217082023-07-10T06:12:13Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Baño Gómez, Vanessa
author
Argüelles Bustillo, Ramón
author
Regueira, R.
author
Guaita Fernández, Manuel
author
2012
El objetivo de este trabajo es el desarrollo de un modelo numérico bidimensional de piezas de madera de Pinus sylvestris L. libre de defectos que prediga su comportamiento frente a solicitaciones externas. Para su desarrollo, fue necesario realizar ensayos experimentales sobre probetas de pequeño tamaño con el fin de obtener los datos de las propiedades mecánicas para el Pinus sylvestris L. de procedencia española. A partir de los datos experimentales obtenidos, se desarrolla un programa de elementos finitos que considera la ortotropía de la madera, la no linealidad de la rama compresión-acortamiento y los distintos módulos de elasticidad a tracción y a compresión para vigas libres de defectos. El programa simula el ensayo experimental de flexión en cuatro puntos según la Norma UNE-EN 408 y aborda la determinación de las tensiones y deformaciones de las vigas de madera en las tres fases de comportamiento: elástica, elastoplástica y plástica.
The objective of this paper is to develop a twodimensional numerical model to simulate the response of Scots pine (Pinus sylvestris L.) defect free timber members in order to predict the behaviour of these members when subjected to external forces. For this purpose, data of the mechanical properties of Scots pine were obtained by performing experimental tests on
specimens. We determined the stresses and deformations of timber beams in the elastic-plastic and plastic phases. In addition, we developed a finite element software that considered the orthotropic nature of timber, the non-linearity of the compression-reduction
branch and the differing moduli of elasticity in tension and compression for Scots pine beams free from defects. The software developed simulates an experimental four point bending test according to UNE-EN 408 Standard.
Baño, V., Bustillo, R. A., Regueira, R., and Fernández, M. G. (2012). Determinación de la curva tensión-deformación en madera de Pinus sylvestris L. para la simulación numérica de vigas de madera libre de defectos. Materiales de construcción, (306), 269-284.
0465-2746
http://hdl.handle.net/10347/21708
10.3989/mc.2012.64110
1988-3226
Madera estructural
Simulación numérica
MEF
Pinus sylvestris L.
Timber construction
Numerical simulation
FEM
Pinus sylvestris L.
Determinación de la curva tensión-deformación en madera de ‘Pinus sylvestris’ L. para la simulación numérica de vigas de madera libre de defectos
oai:minerva.usc.es:10347/267132022-11-15T13:26:20Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2923com_10347_2891com_10347_15613com_10347_15468col_10347_10081col_10347_12110col_10347_15615
00925njm 22002777a 4500
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Vázquez Méndez, Miguel Ernesto
author
Diéguez Aranda, Ulises
author
González Rodríguez, Miguel Ángel
author
2021
Climate change might entail significant alterations in future forest productivity, profitability and management. In this work, we estimated the financial profitability (Soil Expectation Value, SEV) of a set of radiata pine plantations in the northwest of Spain under climate change. We optimized silvicultural interventions using a differentiable approach and projected future productivity using a machine learning model basing on the climatic predictions of 11 Global Climate Models (GCMs) and two Representative Concentration Pathways (RCPs). The forecasted mean SEV for future climate was lower than current SEV (∼22% lower for RCP 4.5 and ∼29% for RCP 6.0, with interest rate = 3%). The dispersion of the future SEV distribution was very high, alternatively forecasting increases and decreases in profitability under climate change depending on the chosen GCM. Silvicultural optimization considering future productivity projections effectively mitigated the potential economic losses due to climate change; however, its ability to perform this mitigation was strongly dependent on interest rates. We conclude that the financial profitability of radiata pine plantations in this region might be significantly reduced under climate change, though further research is necessary for clearing the uncertainties regarding the high dispersion of profitability projections
Forests 2021, 12(7), 899; https://doi.org/10.3390/f12070899
http://hdl.handle.net/10347/26713
10.3390/f12070899
1999-4907
Differentiable optimization
Pinus radiata
Stand-level management
Climate change
Risk modelling
Forecasting Variations in Profitability and Silviculture under Climate Change of Radiata Pine Plantations through Differentiable Optimization
oai:minerva.usc.es:10347/226952020-05-30T02:00:54Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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García Lamparte, Andrés Manuel
author
Santé Riveira, Inés
author
Crecente Maseda, Rafael
author
2010
La estructura urbana condiciona en gran medida su evolución futura. En el presente trabajo
se analiza la evolución de los usos del suelo en un área rururbana de la costa norte de Galicia,
identificando los procesos de cambio de los pequeños asentamientos urbanos característicos
de las áreas periféricas gallegas. El análisis del patrón espacial de los usos urbanos se abordó
mediante el cálculo de una serie de métricas espaciales, para posteriormente estudiar las variables que condicionaron la generación de esos patrones mediante técnicas de regresión logística
y de este modo identificar los procesos que originaron la estructura urbana.
The urban structure conditions greatly its future evolution. In the present work the evolution
of land uses in a rururban area of the Galician north coast is analyzed, by identifying the land
use change processes of the small urban settlements of the periferic Galician areas. The
analysis of the spatial pattern of urban land uses was carried out by means of several spatial
metrics, subsequently the variables that conditioned these patterns were studied through
logistic regression techniques, so the processes causing the urban structure were identified.
Lamparte, A. G., Riveira, I. S., & Maseda, R. C. (2010). Análisis de los factores que condicionan la evolución de los usos del suelo en los pequeños asentamientos urbanos de la costa norte de Galicia. Boletín de la Asociación de geógrafos españoles, (54).
0212-9426
http://hdl.handle.net/10347/22695
Patrones
Crecimiento urbano
Dispersión
Regresión logística
Índices del paisaje
Patterns
Urban growth
Dispersion
Logistic regression
Landscape indexes
Análisis de los factores que condicionan la evolución de los usos del suelo en los pequeños asentamientos urbanos de la costa norte de Galicia
oai:minerva.usc.es:10347/227802022-11-23T12:01:49Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Vega Nieva, Daniel José
author
Nava Miranda, María Guadalupe
author
Calleros Flores, Eric
author
López Serrano, Pablito Marcelo
author
Corral Rivas, José Javier
author
Cruz López, María Isabel
author
Cuahutle, M.
author
Ressl, Rainer
author
Alvarado Celestino, Ernesto
author
González Cabán, Armando
author
Jiménez, Enrique
author
Álvarez González, Juan Gabriel
author
Ruiz González, Ana Daría
author
Burgan, R. E.
author
Preisler, Haiganoush K.
author
Briseño Reyes, Jaime
author
Montiel Antuna, Eusebio
author
2018
Understanding the linkage between accumulated fuel dryness and temporal fire occurrence risk is key for improving decision-making in forest fire management, especially under growing conditions of vegetation stress associated with climate change. This study addresses the development of models to predict the number of 10-day observed Moderate-Resolution Imaging Spectroradiometer (MODIS) active fire hotspots—expressed as a Fire Hotspot Density index (FHD)—from an Accumulated Fuel Dryness Index (AcFDI), for 17 main vegetation types and regions in Mexico, for the period 2011–2015. The AcFDI was calculated by applying vegetation-specific thresholds for fire occurrence to a satellite-based fuel dryness index (FDI), which was developed after the structure of the Fire Potential Index (FPI). Linear and non-linear models were tested for the prediction of FHD from FDI and AcFDI. Non-linear quantile regression models gave the best results for predicting FHD using AcFDI, together with auto-regression from previously observed hotspot density values. The predictions of 10-day observed FHD values were reasonably good with R2 values of 0.5 to 0.7 suggesting the potential to be used as an operational tool for predicting the expected number of fire hotspots by vegetation type and region in Mexico. The presented modeling strategy could be replicated for any fire danger index in any region, based on information from MODIS or other remote sensors.
Vega-Nieva, D.J.; Briseño-Reyes, J.; Nava-Miranda, M.G.; Calleros-Flores, E.; López-Serrano, P.M.; Corral-Rivas, J.J.; Montiel-Antuna, E.; Cruz-López, M.I.; Cuahutle, M.; Ressl, R.; Alvarado-Celestino, E.; González-Cabán, A.; Jiménez, E.; Álvarez-González, J.G.; Ruiz-González, A.D.; Burgan, R.E.; Preisler, H.K. Developing Models to Predict the Number of Fire Hotspots from an Accumulated Fuel Dryness Index by Vegetation Type and Region in Mexico. Forests 2018, 9, 190. https://doi.org/10.3390/f9040190
http://hdl.handle.net/10347/22780
10.3390/f9040190
1999-4907
MODIS
Fire hotspots
Fire occurrence risk
Fire danger systems
Developing Models to Predict the Number of Fire Hotspots from an Accumulated Fuel Dryness Index by Vegetation Type and Region in Mexico
oai:minerva.usc.es:10347/37952022-07-04T12:20:55Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250col_10347_10081col_10347_3773
00925njm 22002777a 4500
dc
Riesco Muñoz, Guillermo
author
Remacha Gete, Andrés
author
Pedras Saavedra, Francisco
author
2006
Se seleccionaron 35 robles procedentes de
varias zonas de Galicia sobre los que se determinaron sus
principales características dendrométricas así como las
condiciones del entorno. Los árboles fueron apeados para
obtener probetas de madera libre de defectos, con
dimensiones normalizadas, en las que se determinó el peso
específico. Se constató la variación del peso específico de
la madera entre individuos, siendo éste mayor en el
duramen. La variación entre individuos fue parcialmente
atribuida a circunstancias ambientales, que influyen de
forma diferente en el peso específico del duramen y en el de
la albura. Las características ambientales más influyentes
en el peso específico fueron el relieve y la localización
geográfica, siendo inapreciable la influencia de las variables
dendrométricas. En cuanto a la localización geográfica, la
madera de roble es más ligera cuanto más al interior de
Galicia, más al oriente y mayor sea la altitud. La variación
de la calidad de la madera entre individuos y entre zonas
justifica que esta especie sea una fuente de diversidad a
conservar. La localización de determinadas estaciones para
el cultivo del roble no garantiza la obtención de madera más
uniforme para la industria, debido a la baja relación entre
peso específico y factores ambientales.
1885-5547
http://hdl.handle.net/10347/3795
Roble
Propiedades de la madera
Peso específico
Fisiografía
Oak
Wood properties
Specific gravity
Physiography
Influencia de la situación geográfica y la fisiografía en la calidad de la madera de "Quercus robur" L.
oai:minerva.usc.es:10347/277182022-11-28T13:12:00Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Vega, José Antonio
author
Arellano Pérez, Stéfano
author
Álvarez González, Juan Gabriel
author
Fernández Filgueira, Cristina
author
Jiménez, Enrique
author
Fernández Alonso, José María
author
Vega Nieva, Daniel José
author
Briones Herrera, Carlos Iván
author
Alonso Rego, Cecilia
author
Fontúrbel, María Teresa
author
Ruiz González, Ana Daría
author
2022
Shrub-dominated ecosystems cover large areas globally and play essential roles in ecological processes. Aboveground biomass expressed on an area basis (AGB) is central to many of the ecological processes and services provided by shrublands and is important as the main fuel source for wildfires. Hence, its accurate estimation in shrublands is crucial for ecologists and land managers. This is especially relevant in fire-prone regions such as NW Spain, where shrublands are an important part of the landscape, providing multiple services, but are severely impacted by wildfires. Although biomass models are available for numerous shrub species at the individual plant level, operational models based directly on easily measured shrub stand attributes are scarce. In this study, equations for estimating AGB and loads of different fuel components by size and condition (live and dead) from stand biometric variables were developed for the nine most prevalent shrub communities in NW Spain. Non-linear iterative seemingly unrelated regression was used to fit compatible systems of equations for estimating fuel loads, with shrub stand height and cover and litter depth as predictors for individual shrub communities and all data combined. In general, the goodness-of-fit statistics indicated that the estimates were reasonably accurate for all communities (grouped and ungrouped). The best results were obtained for AGB and total fuel load, including litter, whereas the poorest results were obtained for standing live and dead fine fuel load. Model performance was reduced when height was the only independent variable, although the reduction was small for most fuel categories, except litter load for which the variability was adequately explained by the litter depth. These results illustrate the feasibility of the stand level approach for constructing operational models of shrub fuel load that are accurate for most of fuel components, while also highlighting the ongoing challenges in live and dead fine fuel modelling. The equations developed represent an appreciable advance in shrubland biomass assessment in the region and areas with similar characteristics and may be instrumental in generating fuel maps, fire management improvement and better C storage assessment by vegetation, among other many uses
Forest Ecology and Management 505 (2022) 119926. https://doi.org/10.1016/j.foreco.2021.119926
http://hdl.handle.net/10347/27718
10.1016/j.foreco.2021.119926
0378-1127
Shrubland biomass
Dominant shrub species
Compatible equations systems
Biometric variables
Litter fuel load
Fuel fractions load
Fuel components
Live and dead fine fuel
Fuel management
Modelling aboveground biomass and fuel load components at stand level in shrub communities in NW Spain
oai:minerva.usc.es:10347/276242023-07-10T06:11:40Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2913com_10347_2891com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_15794col_10347_9747col_10347_15615
00925njm 22002777a 4500
dc
Molina Valero, Juan Alberto
author
Martínez Calvo, Adela
author
Ginzo Villamayor, María José
author
Novo Pérez, Manuel Antonio
author
Álvarez González, Juan Gabriel
author
Montes, Fernando
author
Pérez Cruzado, César
author
2022
Terrestrial Laser Scanning (TLS) devices show great potential for application in Forest Inventories (FIs) as they are capable of registering high resolution point clouds rapidly and automatically. Nevertheless, operational use of TLS for FI purposes has been hampered by the absence of algorithms for processing the acquired data, particularly in the single-scan mode, as occlusions result in loss of information. The R package FORTLS has been developed to overcome this obstacle, as it automates the processing of single-scan TLS point cloud data for forestry purposes and includes several features that deal with occlusions. FORTLS makes use of the main advantage of the single-scan scenario in FI, thus improving the efficiency of data acquisition and post-processing. All of these features of the FORTLS package are potentially valuable for the operational use of TLS in FIs, in combination with inference techniques derived from model-based and model-assisted approaches
Environmental Modelling & Software 150 (2022) 105337
http://hdl.handle.net/10347/27624
10.1016/j.envsoft.2022.105337
1364-8152
Forest monitoring
Forest stands parameters
LiDAR
Precision forestry
Remote sensing
Terrestrial-based-technologies
Operationalizing the use of TLS in forest inventories: the R package FORTLS
oai:minerva.usc.es:10347/220432023-07-10T06:17:01Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Stankova, Tatiana Vassileva
author
Diéguez Aranda, Ulises
author
2012
The height-diameter relationship is an important and extensively investigated forest model, but generalized and mixed-effects models of wider applicability are currently lacking in the forest modeling literature for Scots pine (Pinus sylvestris L.) plantations in Bulgaria. Considering the practical advantages of deterministic and mixed-effects models, the present study aims to derive a generalized deterministic height-diameter relationship and a simple mixed-effects model for plantation-grown Scots pine in Bulgaria. Ten generalized and six local models of adequate mathematical properties were selected and examined in several subsequent steps with a representative data set. A deterministic model was derived for tree height reconstruction from the individual tree diameters, stand dominant height and diameter, number of trees per hectare and stand age. Mixed-effects models were developed from the individual-tree and stand diameters and heights applicable to determine the height-diameter relationship in field surveys. Both types of models can be applied with confidence, according to their advantages and specifications, for estimating the height-diameter relationship of Scots pine plantations in Bulgaria, presenting a unique contribution for the particular species, study area and type of model. The choice of the tested models is relevant to the height-diameter relationship investigation of biologically related and geographically close species and types of stands and the study procedure allows repetition of the work to provide reliable solutions of the problem where information on such type of model is deficient or incomplete
Vassileva Stankova, T., & Diéguez-Aranda, U. (2012). Height-diameter relationships for Scots pine plantations in Bulgaria: optimal combination of model type and application. Annals Of Forest Research, 56(1), 149-163. doi:10.15287/afr.2013.50
1844-8135
http://hdl.handle.net/10347/22043
10.15287/afr.2013.50
2065-2445
Deterministic model
Height-diameter relationship
Mixed-effects model
Model localization
Practical model application
Scots pine plantations
Height-diameter relationships for Scots pine plantations in Bulgaria: optimal combination of model type and application
oai:minerva.usc.es:10347/212162020-04-08T02:00:48Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Ortiz Sanz, Juan Pedro
author
Gil Docampo, María de la Luz
author
Rego Sanmartín, María Teresa
author
Arza García, Marcos
author
2019
0099-1112
http://hdl.handle.net/10347/21216
10.14358/PERS.85.5.338
2374-8079
The Future Professionals in Geomatics
oai:minerva.usc.es:10347/322632024-02-03T01:03:00Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Carballo, Rodrigo
author
López, Iván
author
Taveira Pinto, Francisco
author
Iglesias, Gregorio
author
2020
Air compressibility is often neglected in experimental work due to practical difficulties, even though it is known to affect the performance of OWC wave energy converters. The key question, of course, is to what extent. In this work the impact of air compressibility on the capture width ratio is thoroughly quantified by means of a comprehensive experimental campaign, with no fewer than 330 tests encompassing a wide range of wave conditions and levels of turbine-induced damping, and two experimental set-ups: one designed to account for air compressibility, the other to neglect it. This approach is complemented with the use of the RANS-based CFD model OpenFOAM® to calibrate the pressure-vs-flowrate curves, which enables the flowrate to be determined based on the pressure drop measurements from the physical model. We find that the errors that derive from disregarding air compressibility may lead to either under- or over-predictions of power output, and are highly dependent on the operating conditions, more specifically the wave conditions (sea state) and turbine-induced damping.
I. López, R. Carballo, F. Taveira-Pinto, G. Iglesias, Sensitivity of OWC performance to air compressibility, Renewable Energy, Volume 145, 2020, Pages 1334-1347, ISSN 0960-1481, https://doi.org/10.1016/j.renene.2019.06.076.
0960-1481
http://hdl.handle.net/10347/32263
10.1016/j.renene.2019.06.076
1879-0682
Wave energy
Wave power
Oscillating water column
Physical modelling
CFD
Capture-width ratio
Sensitivity of OWC performance to air compressibility
oai:minerva.usc.es:10347/220452020-05-06T02:01:46Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Amiama Ares, Carlos
author
Bueno Lema, Javier
author
Álvarez López, Carlos José
author
Riveiro Valiño, José Antonio
author
2011
In this paper, the performance of a manual GPS guidance system to assist farming operations is evaluated. The
distribution of granular fertilizer was simulated in order to discretize areas with excessive application of fertilizers
and areas with fertilizer application rates below the intended rate. The path of travel followed by a tractor with the
manual GPS guidance system was analysed and compared with a commercial parallel tracking system and without
guidance assistance. In addition, the analysis evaluated how the use of manual GPS guidance systems improves the
performance of field operations that require large distances between passes. Under the experimental conditions used,
the best results were obtained using a commercial parallel tracking system but, for our purposes, small differences
were observed between the results obtained with the commercial system and the results obtained with the developed
manual GPS guidance system, getting pass-to-pass average error values of 0.26 and 0.73 m, respectively. The results
obtained with both systems were significantly better than the results obtained when no guidance assistance was used.
In our trials, area with appropriate fertilizer rate was clearly increased when guidance assistance was used. Values of
area with correct fertilizer rate applied ranged between 87% with commercial parallel tracking and 59% without
guidance assistance. The use of the manual GPS guidance system presented in this paper has proved sufficient to obtain
good results for mechanical fertilizer spreading
En este trabajo se ha evaluado un sistema de asistencia al guiado manual para la realización de labores agrícolas. Se simuló la distribución de fertilizante granulado con el objetivo de discretizar áreas con excesiva cantidad
de fertilizante y áreas con cantidades inferiores a las previstas. Se comparó la trayectoria seguida por un tractor utilizando el sistema GPS de asistencia al guiado manual con un sistema comercial de guiado paralelo, y sin asistencia al guiado. Nuestro análisis ha permitido evaluar las mejoras que estos sistemas suponen para la realización de
labores que requieran elevadas distancias entre pasadas. En nuestras condiciones, los mejores resultados se obtuvieron con un sistema comercial de guiado paralelo, si bien, considerando nuestro propósito, las diferencias fueron reducidas respecto a las obtenidas con el sistema de asistencia al guiado manual desarrollado, con valores medios de error pasada a pasada de 0,26 y 0,73 m, respectivamente. Los resultados obtenidos con ambos sistemas
fueron significativamente mejores que los obtenidos cuando no se utiliza ningún sistema de asistencia. En nuestros ensayos, el área con dosis adecuadas de fertilizante se incrementó de forma clara con la utilización del sistema de asistencia al guiado manual. Los valores de superficie con dosis correctas de fertilizante aplicado oscilaron
entre el 87% con el sistema comercial de guiado paralelo y el 59% sin asistencia al guiado. Los resultados obtenidos evidencian que el sistema de asistencia al guiado manual desarrollado es válido para la aplicación mecánica de fertilizantes
Amiama Ares, C. et al. (2011). Manual GPS guidance system for agricultural vehicles. Spanish journal of agricultural research, nº 3, pp. 702-712
1695-971X
http://hdl.handle.net/10347/22045
10.5424/sjar/20110903-353-10
2171-9292
Parallel tracking
Precision agriculture
Spreader simulation
Agricultura de precisión
Guiado paralelo
Simulación de fertilización mecánica
Manual GPS guidance system for agricultural vehicles
oai:minerva.usc.es:10347/223942021-05-21T07:33:03Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Fernández Nogueira, David
author
Corbelle Rico, Eduardo José
author
2018
This work aims to provide a comprehensive, wall-to-wall analysis of land use/cover changes in the continental areas of Portugal and Spain between 1990 and 2012. This overall objective is developed into two main research questions: (1) Whether differences between the extent and prevalence of changes exist between both countries and (2) which are the hotspots of change (areas where a given land use/cover transition dominates the landscape) in each country. We used Corine Land Cover in three different points in time (1990, 2000, 2012) to explore eight characteristic land cover transitions and carried out a cluster analysis at LAU2 level (municipalities in Spain, parishes in Portugal) that allowed to identify the areas in which each transition was dominant. The main findings include the decline of agricultural area and the increase of urbanized and artificial covers in both countries, but different trends followed by forest cover, with an increase in Spain and a decrease in Portugal. At the same time, the spatial analysis provided an overview of the main gradients of change related to tensions between agricultural intensification–extensification, on the one hand, and deforestation–afforestation, on the other
Fernández-Nogueira, D.; Corbelle-Rico, E. Land Use Changes in Iberian Peninsula 1990–2012. Land 2018, 7, 99
http://hdl.handle.net/10347/22394
10.3390/land7030099
2073-445X
Land use/cover change
Corine Land Cover
Iberian Peninsula
Cluster analysis
Intensification
Afforestation
Extensification
Urbanization
Deforestation
Land use changes in Iberian Peninsula 1990–2012
oai:minerva.usc.es:10347/138102020-01-31T18:02:36Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Fernández Parajes, José
author
Riesco Muñoz, Guillermo
author
2015-10
La depuración de aguas residuales en pequeños núcleos debe orientarse hacia alternativas diferentes
a las que se suelen aplicar en poblaciones de mayor tamaño. En este sentido, la tecnología actual
ofrece un amplio abanico de tratamientos, especialmente los denominados naturales o de bajo
coste. Teniendo en cuenta los últimos desarrollos en este campo, en el presente trabajo se aplica una
metodología de ayuda a la toma de decisiones para facilitar la elección del sistema de tratamiento
más adecuado en núcleos rurales de Galicia. Los núcleos escogidos para el análisis abarcan gran parte
de la diversidad del problema en el ámbito rural gallego.
FERNÁNDEZ-PARAJES, J.; RIESCO MUÑOZ, G. 2015. Selección del tratamiento óptimo de aguas residuales para poblaciones del medio rural de Galicia. Industria Química, 28, 86-99.
2340-2113
http://hdl.handle.net/10347/13810
Tratamiento de aguas
Sistemas ecológicos de depuración de aguas residuales
Aguas residuales en municipios pequeños
Selección del tratamiento óptimo de aguas residuales para poblaciones del medio rural de Galicia
oai:minerva.usc.es:10347/301492023-06-12T12:34:03Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Núñez Temes, Carlos
author
Bastos Costas, Guillermo
author
Arza García, Marcos
author
Castro Ponte, Alberte
author
Lorenzana Fernández, José Antonio
author
Ortiz Sanz, Juan Pedro
author
Portela Barral, María
author
Gil Docampo, María de la Luz
author
Prego Martínez, Francisco Javier
author
2022
This study aims to introduce the use of 3D-digital image correlation (DIC) to the in situ testing of pavements and to support the development of techniques for a rapid evaluation of the conservation status of existing roads. Little research was found on this topic. The passage of a car wheel on an asphalt pavement was adopted as a case study. The DIC measurements were compared to those gathered by contact sensors. From a qualitative point of view, the DIC measurements captured the realistic shape of a deflection basin. From a quantitative point of view, the deflection values provided by the DIC system had a mean error of 0.015 mm and a standard deviation of 0.011 mm. At the moment of highest load, these errors had a mean value and standard deviation of − 0.016 mm and 0.021 mm, respectively. Thus, to improve the accuracy of the system, we propose modifying the camera support, speckle pattern, and control of natural light
Núñez-Temes, C., Bastos, G., Arza-García, M. et al. Assessment of pavement deflection under vehicle loads using a 3D-DIC system in the field. Sci Rep 12, 9491 (2022). https://doi.org/10.1038/s41598-022-13176-3
http://hdl.handle.net/10347/30149
10.1038/s41598-022-13176-3
2045-2322
Civil engineering
Engineering
Assessment of pavement deflection under vehicle loads using a 3D-DIC system in the field
oai:minerva.usc.es:10347/307832023-06-24T02:02:48Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Gil Docampo, María de la Luz
author
Peña Villasenín, Simón
author
Bettencourt, Ana
author
Ortiz Sanz, Juan Pedro
author
Peraleda Vázquez, Sara
author
2023
Cultural heritage in coastal or shallow aquatic environments is often located in areaswhere access is difficult or where accurate survey and documentation may notalways be possible with terrestrial or aquatic equipment. The combination of photo-grammetry and unmanned aerial vehicles (UAVs) generates a range of possibilitiesacross multiple sectors, including history, ethnography and cultural heritage studies.Additionally, these methods can be used to prospect new archaeological sites. Thisarticle presents three case studies that use UAV techniques and Structure fromMotion and Multiview Stereo (SfM-MVS) photogrammetry to conduct topographicand geometric registrations of archaeological, historical and ethnographic sites (someof which are classified as cultural heritage sites). These examples are located incoastal or shallow aquatic environments that are difficult to survey with traditionalmethods. The results show that it is possible to carry out detailed geometric registra-tion and heritage prospection over large coastal or shallow aquatic environmentsusing a low-cost UAV. Furthermore, the results of this work show great advantagesin terms of cost and quality, even in cases where the seabed is below a shallow watercolumn. Other particularities of SfM-MVS application in aquatic environments arediscussed. From an interdisciplinary perspective, this methodology will offer newpossibilities for the study, restoration and conservation of archaeological, historicaland ethnographic monuments
Gil-Docampo, M., Peña-Villasenín, S., Bettencourt, A. M. S., Ortiz-Sanz, J., & Peraleda-Vázquez, S. (2023). 3D geometric survey of cultural heritage by UAV in inaccessible coastal or shallow aquatic environments. Archaeological Prospection, 1– 16. https://doi.org/10.1002/arp.1901
1075-2196
http://hdl.handle.net/10347/30783
10.1002/arp.1901
1099-0763
3D modelling
Aerial prospecting
Close-range photogrammetry
Cultural heritage
3D geometric survey of cultural heritage by UAV in inaccessible coastal or shallow aquatic environments
oai:minerva.usc.es:10347/37802022-07-04T12:18:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250com_10347_2956col_10347_10081col_10347_3771col_10347_9747
00925njm 22002777a 4500
dc
Escariz Ferrín, Avelino
author
Miranda Barrós, David
author
Álvarez López, Carlos José
author
2005
En la conferencia sobre Desarrollo Rural de
Salzburgo en 2003, se reconocía la diversidad de Europa en
cuanto a sus paisajes, sus sistemas de producción, así
como a su capacidad de retener y atraer población. Es en
este punto donde realizamos nuestra contribución, para que
el hecho de pertenecer a un núcleo rural no suponga una
depreciación de la calidad de vida y del bienestar. Surge así
la necesidad de evaluación, no sólo de las necesidades de
la población rural sino de la valoración del bienestar rural,
entendido el término como complejo y de difícil valoración.
Por otra parte, la Unión Europea señala que el desarrollo
rural se basa en mejorar la calidad de vida, interviniendo en
la calidad ambiental, el nivel de renta y las condiciones de
vida y trabajo. La evaluación de la calidad de vida, se puede
acometer mediante la creación de un marco conceptual de
cálculo, donde se reflejen conjuntamente las distintas
variables que intervienen en el análisis, mediante la
creación de una batería de indicadores multivariable. En
esta aproximación al conocimiento de la calidad de vida se
realizó una diferenciación espacial en 22 comarcas de
Galicia, tomando como base el concepto del bienestar rural
y la opinión de los agricultores.
1885-5547
http://hdl.handle.net/10347/3780
Desarrollo rural
Indicadores multivariantes
Encuestas de opinión
Rural development
Multivariate indicators
Opinion surveys
La opinión de los agricultores gallegos sobre sus condiciones de vida, el desarrollo rural en Galicia
oai:minerva.usc.es:10347/226482020-05-29T02:01:39Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Muñoz, Fernando
author
Cancino, Jorge
author
Rodríguez Soalleiro, Roque
author
Olave, Rodrigo
author
2018
Se establecieron cultivos experimentales de Miscanthus x giganteus en tres sitios contrastantes del centro-sur de Chile para evaluar su crecimiento y potencial energético. Al segundo año de crecimiento el cultivo presentó grandes diferencias entre sitios, altura (52,1 a 158,2 cm), rendimiento en biomasa (1,1 a 9,0 Mg ha-1), contenido de cenizas (3,8 a 9,6%) y poder calorífico (16,64 a 18,14 MJ kg-1). La composición química de la biomasa indicó celulosa en un 36%, hemicelulosa con 22,3% y lignina con 26,9%. El análisis elemental indicó 41,9% de C y 6,6% de H. Miscanthus x giganteus presenta condiciones para su utilización en la generación de energía en Chile.
Experimental crops of Miscanthus x giganteus were planted in three contrasting sites in Chile south central to evaluate its growth and energy potential. In the second year of growth, the crop exhibited large differences among sites regarding height (52.1 to 158.2 cm), biomass yield (1.1 to 9.0 Mg ha-1), ash content (3.8 to 9.6%) and calorific value (16.64 to 18.14 MJ kg-1). The chemical composition of the biomass indicated cellulose 36%, hemicellulose 22.3% and lignin 26.9%. Elemental analysis indicated C and H content of 41.9% and 6.6% respectively. Therefore, Miscanthus x giganteus offers suitable attributes to be used for energy generation in Chile.
Muñoz, Fernando; Cancino, Jorge; Rodríguez, Roque; Olave, Rodrigo (2018) "Evaluación de crecimiento, rendimiento y calorimetría de biomasa de Miscanthus x giganteus (Poaceae) establecido en el centro-sur de Chile: ". En: Revista de la Facultad de Ciencias Agrarias, Vol. 50, no. 1, p. 47-60. https://bdigital.uncu.edu.ar/10695.
0370-4661
http://hdl.handle.net/10347/22648
1853-8665
Biomasa
Dendroenergía
Cultivos dendroenergéticos
Energía renovable
Biomass
Crops for wood energy
Renewable energy
Evaluación de crecimiento, rendimiento y calorimetría de biomasa de Miscanthus x giganteus (Poaceae) establecido en el centro-sur de Chile
oai:minerva.usc.es:10347/226922020-05-30T02:01:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Diéguez Aranda, Ulises
author
Grandas Arias, José Antonio
author
Álvarez González, Juan Gabriel
author
Gadow, Klaus von
author
2006
A model for predicting the height growth of even-aged, birch (Betula pubescens Ehrh.) dominated stands in Galicia (north-western Spain) was developed. Data from stem analysis of 214 trees were used for model construction. Two dynamic site equations derived with the generalized algebraic difference approach (GADA) were tested, which combine compatible site index and height models in one common equation. Both equations are base-age invariant and directly estimate height and site index from any height and age. The fittings were done in one stage using the base-age-invariant dummy variables method. A second-order continuous-time autoregressive error structure was used to correct the inherent autocorrelation of the longitudinal data used in this study. Cieszewski’s model best described the data. This model is therefore recommended for height growth prediction and site classification of birch stands in Galicia.
Diéguez-Aranda, U., Grandas-Arias, J. A., Álvarez-González, J. G., & von Gadow, K. (2006). Site quality curves for birch stands in north-western Spain. Silva Fennica, 40(4), 631.
0037-5330
http://hdl.handle.net/10347/22692
10.14214/sf.319
2242-4075
Site quality
Generalized algebraic difference approach
Base-age invariant dynamic equation
Hossfeld model
Betula pubescens
Galicia
Site Quality Curves for Birch Stands in North-Western Spain
oai:minerva.usc.es:10347/330832024-03-21T09:21:42Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Vega, José Antonio
author
Álvarez González, Juan Gabriel
author
Arellano Pérez, Stéfano
author
Alonso Rego, Cecilia
author
Ruiz González, Ana Daría
author
2024
Geospatial fire behaviour and fire hazard simulators, fire effects models and smoke emission software commonly use standard fuel models in order to simplify data collection and the inclusion of complex fuel scenarios. These fuel models are often mapped using remotely sensed data. However, given the great complexity of fuelbeds, with properties that vary widely in both time and space, the use of these standard fuel models can greatly limit accurate fuel mapping. This affects fuel hazard assessment, fuel reduction treatment plans, fire management decision-making and evaluation of the environmental impact of wildfire. In this study, we developed unique customized fire behaviour fuel models for shrub and bracken communities, by using k-medoids clustering analysis based on both fuel structural characteristics and potential fire behaviour. We used an original database of 722 destructive sample plots in nine different shrub and bracken communities covering the entire distribution area in Galicia (NW Spain), one of the regions in Europe most affected by forest fires. Measurements of cover, height and fuel fractions loads differentiated by size and vegetative state (live or dead) were used to estimate the potential rate of fire spread with five different models including fireline intensity, heat per unit area and the flame length for each sampling site and considering extreme environmental conditions. The optimal number of clusters was established by combining practical knowledge about the shrubland communities under study and their associated fire behaviour, with maximization of the mean value of the silhouette variable and minimization of the within-cluster sum of squares. The structural characteristics of the medoids derived from the analysis were associated with each of the proposed customized fuel models. Finally, a simple dichotomous classification based only on shrub height was developed to enable construction of spatially explicit fuel model maps based on remotely sensed data. Thus, the methodology applied allows generation of a more realistic representation of fuel distribution in the landscape, based on fuel structure measurements of natural regional ecosystems rather than on the use of standard models. We believe that the proposed methodology is generally applicable to communities composed of other shrub and fern species in different biogeographical regions.
Journal of Environmental Management Volume 351, February 2024, 119831
0301-4797
http://hdl.handle.net/10347/33083
10.1016/j.jenvman.2023.119831
Wildland fuels
Fuel models
Medoids
Cluster analysis
Fire behaviour
Fire management
Fuels classification
Developing customized fuel models for shrub and bracken communities in Galicia (NW Spain)
oai:minerva.usc.es:10347/181662022-02-11T11:23:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Arza García, Marcos
author
Gil Docampo, María de la Luz
author
Ortiz Sanz, Juan Pedro
author
2019-01-22
Photogrammetry is a cost-effective and versatile technique used for the threedimensional (3D) registration of archaeological heritage sites. Managing datasets of
heterogeneous images in terms of camera type, elevation platform, position or
acquisition time can now be addressed by structure from motion (SfM) software via
bundle adjustment in a single block based on collinearity principles. This development
enables new possibilities with regard to data completeness assurance for 3D
documentation, even for complex sites with occlusive elements and hidden areas.
However, hybrid photogrammetry in large datasets often requires multiple
photogrammetric blocks that must be processed individually and subsequently aligned
to obtain a unified point cloud. In this paper, we discuss the steps required to
homogenize the information and the methods used to perform block alignment in these
cases. A case study of low-altitude aerial photogrammetry with several cameras and
platforms is presented for the Roman camp of A Cidadela in NW Spain as a
representative example of an archaeological site that is difficult to survey using a single
photogrammetric platform. The relatively large expanse of the area and the fact that it is
partially covered by a protective structure constitute an ideal framework for the fusion
of multiplatform imagery. The most accurate digital surface model (DSM) was obtained
via point-based method fusion, during which subsets are aligned based on automatically
extracted tie points (TPs) between the dense point clouds; however, point-based method
fusion is very time consuming. When hardware capabilities allow, conducting the
process in a single block is preferable, which is a noticeably more accurate procedure
than independent block fusion
Arza-García, M., Gil-Docampo, M., & Ortiz-Sanz, J. (2019). A hybrid photogrammetry approach for archaeological sites: Block alignment issues in a case study (the Roman camp of A Cidadela). Journal Of Cultural Heritage. doi: 10.1016/j.culher.2019.01.001
1296-2074
http://hdl.handle.net/10347/18166
10.1016/j.culher.2019.01.001
Modelling
Hidden areas
Aerial
UAV
Pole
A hybrid photogrammetry approach for archaeological sites: Block alignment issues in a case study (the Roman camp of A Cidadela)
oai:minerva.usc.es:10347/275112022-02-09T03:02:25Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_9747col_10347_15614
00925njm 22002777a 4500
dc
Molina Valero, Juan Alberto
author
Rodríguez Ruiz, Joel
author
Pérez Cruzado, César
author
Martínez Calvo, Adela
author
2022
Este libro contiene las actas del Workshop sobre Teledetección Próxima Terrestre para Aplicaciones Forestales que tuvo lugar los días 1, 2 y 3 de septiembre de 2021 en la Escuela Politécnica Superior de Ingeniería del Campus Terra de la Universidade de Santiago de Compostela (Lugo, España). Este workshop tuvo como objetivo la puesta en común de resultados científicos y aplicaciones prácticas de estas tecnologías en el ámbito forestal, así como la práctica de aspectos operativos en la toma y análisis de datos. Para ello, constó de jornadas científico-técnicas con formato de congreso (híbrido presencial-telemático), sesiones prácticas de toma de datos en campo y de su posterior análisis y procesado en ordenador mediante la impartición de talleres (presencial), y de una mesa redonda de reflexión sobre el estado del arte de estas tecnologías en todos los ámbitos forestales implicados. Este evento fue organizado conjuntamente por los grupos de investigación GI-1716 Proyectos y Planificación (PROEPLA) y GI-1837 Unidad de Gestión Ambiental y Forestal Sostenible (UXAFORES) de la Universidade de Santiago de Compostela. La celebración del workshop fue financiada por la Diputación de Lugo y la Universidade de Santiago de Compostela, a través de la Convocatoria de axudas 2021 para a realización de actividades de investigación e/ou transferencia no ámbito do desenvolvemento rural no Campus de Lugo, y por la Consellería de Educación, Universidade e Formación Profesional de la Xunta de Galicia que, mediante el Programa de Consolidación y Estructuración de Unidades de Investigación Competitivas, financia los grupos de referencia competitiva PROEPLA (GRC GI-1716, ED431C 2021/27) y UXAFORES (GRC GI-1837, ED431C 2018/07). Además, el evento fue patrocinado por las empresas ÁLAVA INGENIEROS y GRAFINTA, que han participado como sponsors vinculados a dos de las tecnologías de teledetección próxima terrestre objeto de la actividad: escáner láser terrestre (TLS) y localización simultánea y mapeo (SLAM), respectivamente. En la organización del Workshop sobre Teledetección Próxima Terrestre para Aplicaciones Forestales se contó con la colaboración del Campus Terra y la Escuela Politécnica Superior de Ingeniería de la Universidade de Santiago de Compostela, que proporcionaron los espacios en los que tuvieron lugar de forma presencial las distintas sesiones y talleres del workshop
978-84-09-37465-6
D. L.: C 17-2022
http://hdl.handle.net/10347/27511
LiDAR
Fotogrametría
Imágenes estereoscópicas
Sensores remotos
SLAM
TLS
Actas del Workshop sobre Teledetección Próxima Terrestre para Aplicaciones Forestales
oai:minerva.usc.es:10347/37832022-07-04T12:18:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2917com_10347_2891com_10347_3770com_10347_250com_10347_2956col_10347_10081col_10347_11706col_10347_3771col_10347_9747
00925njm 22002777a 4500
dc
Álvarez González, Juan Gabriel
author
Balboa Murias, Miguel Ángel
author
Merino García, Agustín
author
Rodríguez Soalleiro, Roque
author
2005
En este trabajo se ha caracterizado la
acumulación de biomasa arbórea en masas adultas de
Eucalyptus globulus y Pinus pinaster en Galicia. Diferentes
intereses industriales, energéticos y ambientales han
motivado que en los últimos años el análisis de las distintas
posibilidades de aprovechamiento de la biomasa forestal
esté adquiriendo un creciente protagonismo, por lo que la
cuantificación de la biomasa arbórea de estos sistemas
forestales constituye un primer paso fundamental e
ineludible. La estimación de la biomasa arbórea se basa en
el empleo de un sistema de ecuaciones que relacionan el
peso de cada fracción arbórea con variables de árbol
sencillas de medir en campo. El ajuste de este sistema de
ecuaciones se ha realizado de forma simultánea empleando
datos procedentes de un muestreo destructivo de 75
eucaliptos y 125 pinos seleccionados en 12 masas adultas.
En las masas de eucalipto, los valores de acumulación de
biomasa arbórea variaron entre 142 y 426 Mg ha-1. Estos
valores oscilaron entre 203 y 438 Mg ha-1 para las masas
de pino. Los porcentajes registrados de biomasa de
madera, corteza y copa, con respecto al total de biomasa
aérea fueron 82; 7 y 11 % para eucalipto y 68; 11 y 21 %
para pino.
1885-5547
http://hdl.handle.net/10347/3783
Modelización
Fracciones arbóreas
Seemingly unrelated regression
Modelling
Tree components
Estimación de la biomasa arbórea de "Eucalyptus globulus" y "Pinus pinaster" en Galicia
oai:minerva.usc.es:10347/322552024-02-03T01:03:17Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Carballo, Rodrigo
author
Iglesias, Gregorio
author
López, Iván
author
2019
The energy conversion performance of oscillating water column (OWC) wave energy converters at a specific site is often studied by means of analytical models. Based on linear theory, these models lose accuracy when viscous losses and turbulence become significant—more generally, when nonlinear effects play a role, as they often do in real operating conditions. In this work we apply a novel methodology based on a combination of numerical modelling and laboratory tests to investigate OWC performance without these shortcomings. First, high-resolution wave resource characterisation matrices are obtained by means of numerical modelling. Second, the resource matrices are combined with the OWC efficiency matrices obtained through laboratory tests and, importantly, including the effects of turbine-induced damping and air compressibility—usually disregarded in small-scale laboratory tests, but relevant for full-size (prototype) devices. The combined matrices thus obtained express, through a wave height-period distribution, the energy captured by the OWC for different values of the damping coefficient. On this basis, developers can select the most appropriate value of turbine-induced damping for a given site, based on performance values. The implementation of the novel methodology is illustrated through a case study in Galicia (NW Spain), in which three deployment sites are considered. We find that the turbine-induced damping must be matched to the wave climate of the site for an OWC device to achieve high performance; indeed, changes in damping cause variations in the total annual energy captured of up to 11%, which increase to 25% for specific sea states.
I. López, R. Carballo, G. Iglesias, Site-specific wave energy conversion performance of an oscillating water column device, Energy Conversion and Management, Volume 195, 2019, Pages 457-465, ISSN 0196-8904, https://doi.org/10.1016/j.enconman.2019.05.030.
0196-8904
http://hdl.handle.net/10347/32255
10.1016/j.enconman.2019.05.030
Wave energy
Characterisation matrices
OWC
Air compressibility
Physical modelling
Capture width ratio
Site-specific wave energy conversion performance of an oscillating water column device
oai:minerva.usc.es:10347/192572020-01-31T10:26:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_8426com_10347_250col_10347_10081col_10347_18912
00925njm 22002777a 4500
dc
Álvarez López, Carlos José
author
Palmeiro Ramos, Manuel
author
Crecente Maseda, Rafael
author
2002
Este traballo comenta os aspectos máis significativos do proceso proxectual seguido desde o encargo de realizar unha candidatura á Iniciativa LIFE-MEDIO AMBIENTE, ata a actualidade, cando faltan escasos meses para finaliza-la execución do proxecto. Pretendemos discuti-los termos de referencia do proceso de formulación, da fase de xestión, da execución e, por último, formularémo-las previsións para a explotación. A idea do presente proxecto partiu da necesidade de diversificación da economía rural e da relevancia do turismo (de natureza), como posible xerador potencial de efectos multiplicadores, tanto da formación de emprego como do rendemento económico, todo iso dentro da conservación e da revalorización dun medio de características ambientais significativas e degradadas.
A través do Proxecto LIFE Tambre I, aprobado e cofinanciado pola Dirección Xeral XI da Comisión Europea, inténtase valoriza-los recursos naturais e, ó mesmo tempo, compatibiliza-lo seu aproveitamento coa actividade industrial de producción de enerxía eléctrica. As actividades propostas no proxecto están encamiñadas á creación dunha nova funcionalidade do medio natural: o turismo rural. Ademais, como peza fundamental para a articulación de tódalas actividades e a súa conservación ó longo do tempo, estase elaborando un Plan de Ordenación do Medio Físico, co que se intentan cimenta-los piares básicos da economía ambiental da zona: a administración dos recursos, a súa distribución e a busca dos seus limites de dispoñibilidade durante a fase de explotación do proxecto
This assignment comments on the most significant aspects of the Project “LIFE-MEDIOAMBIENTE” from the date of its commission until now, a few months before final implementation of the project. Our purpose is to discuss the terms of reference for the processes and the execution. Finally, we will explain the previsions for its use. The idea for the current Project arises from the need for the diversion of the rural economy and from the relevance of rural turism as a potential trigger to increase, not only job creation, but also economic performance. This would occur in conjunction with the conservation and reassignment of a medium with distinctive environmental characteristics.
The Project LIFE Tambre I, approved and financed by the DGXI of the European Comission, at-tempts to evaluate the natural resources and, at the same time, make it compatible with the exploitation of the industrial production of electrical energy. The recommendations proposed by the Project, have the objective of creating a new systems of management of the environment, rural turism. Moreover, as a key piece of the coordination of all these activities and their conservation for the long-term future, a new plan for the coordination of the environment is being elaborated on. This plan intends to cement the basic pillars of the environment economy of the region: ad-ministration of resources, their distribution and the exploration of the available limits during the implementation phase of the Project
Este trabajo comenta los aspectos mas significativos del proceso proyectual seguido desde el encargo de realizar una candidatura a la Iniciativa LIFE-MEDIOAMBIENTE, hasta la actualidad, cuando faltan escasos meses para finalizar la ejecución del proyecto. Pretendemos discutir los términos de referencia del proceso de formulación, de la fase de gestión, de la ejecución y, por último, formularemos las previsiones para la explotación. La idea del presente proyecto partió de la necesidad de diversificación de la economía rural y de la relevancia del turismo (de naturaleza), como posible generador potencial de efectos multiplicadores, tanto de la formación de empleo como del rendimiento económico, todo ello dentro de la conservación y de la revalorización de un medio de características ambientales significativas y degradadas.
A través del Proyecto LIFE Tambre I, aprobado y cofinanciado por la Dirección General XI de la Comisión Europea, se intenta valorizar los recursos naturales y, al mismo tiempo, compatibilizar su aprovechamiento con la actividad industrial de producción de energía eléctrica. Las actividades propuestas en el proyecto están encaminadas a la creación de una nueva funcionalidad del medio natural: el turismo rural. Además, como pieza fundamental para la articulación de todas las actividades y su conservación a lo largo del tiempo, se está elaborando un Plan de Ordenación del Medio Físico, con el que se intentan cimentar los pilares básicos de la economía ambiental de la zona: la administración de los recursos, su distribución y la búsqueda de sus limites de disponibilidad durante la fase de explotación del proyecto
Revista Galega de Economía, vol. 11, núm. 2 (2002), pp. 1-21 ISSN 1132-2799
1132-2799
http://hdl.handle.net/10347/19257
2255-5951
LIFE-MEDIO AMBIENTE
Desenvolvemento rural sostido
Turismo rural
Recuperación ambiental
LIFE ENVIRONMENT
Sustainable rural development
Rural turism
Environmental recovery
Desarrollo rural sostenido
Ambiente e desenvolvemento rural. Proxecto LIFE99 ENV/E/00286 "Rehabilitación Tambre I Proxecto Piloto"
oai:minerva.usc.es:10347/222282020-05-13T02:00:55Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956col_10347_10081col_10347_9747
00925njm 22002777a 4500
dc
Barrasa Rioja, Martín
author
Lamosa Quinteiro, Santiago
author
Fernández Rodríguez, María Dolores
author
Fernández Rodríguez, María Elena
author
2012
The influence of the type of farming on harmful gas exposures to carbon dioxide (CO2
), ammonia (NH3
) and hydrogen
sulfide (H2
S) was assessed from the perspective of animal welfare and occupational hygiene. Summer data of H2
S, NH3
and CO2
concentrations and of environmental parameters were collected from 31 farms. The indices of exposure for longterm exposures to NH3
suggest the lowest acceptability of exposure was observed on poultry farms. CO2
had the highest
dependence on production activity. For H2
S, no differences were found based on farming activity. Both the stocking density
and volume of air available affected the daily exposure and the index of exposure to CO2
. Significant differences were observed
between hourly CO2
concentrations, depending on the level of activity inside the building. A positive correlation was found
between gas concentrations and temperature increase. All values of daily and short-term exposures were below exposure
limit values, which suggests that exposure conditions were appropriate for workers’ health during the measurement period.
Analysis of the working hours and average hourly concentration of gases during the times of day, with presence of workers
inside the farm buildings, revealed significant differences for CO2
.
Barrasa, M., Lamosa, S., Fernandez, M. D., & Fernandez, E. (2012). Occupational exposure to carbon dioxide, ammonia and hydrogen sulphide on livestock farms in north-west Spain. Annals of Agricultural and Environmental Medicine, 19(1).
1232-1966
http://hdl.handle.net/10347/22228
1898-2263
Livestock farms
Harmful gases
Animal welfare
Occupational hygiene
Occupational exposure to carbon dioxide, ammonia and hydrogen sulphide on livestock farms in north-west Spain
oai:minerva.usc.es:10347/158652023-07-10T06:16:43Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Görgens, Eric B
author
García-Gutiérrez, Jorge
author
Guerra Hernández, Juan
author
Estraviz Rodriguez, Luiz Carlos
author
Tomé, Margarida
author
González Ferreiro, Eduardo Manuel
author
2017-02-17
This study aimed to develop ALS-based models for estimating stem, crown and
aboveground biomass in three types of Mediterranean forest, based on low density ALS
data. Two different modelling approaches were used: (i) linear models with different
variable selection methods (Stepwise Selection [SS], Clustering/Exhaustive search [CE]
and Genetic Algorithm [GA]), and (ii) previously Published Models (PM) applicable to
diverse types of forest. Results indicated more accurate estimations of biomass components
for pure Pinus pinea L. (rRMSE = 25.90-26.16%) than for the mixed (30.86-36.34%) and
Quercus pyrenaica Willd. forests (32.78-34.84%). All the tested approaches were valuable,
but SS and GA performed better than CE and PM in most cases
Juan Guerra-Hernández, Eric Bastos Görgens, Jorge García-Gutiérrez, Luiz Carlos Estraviz Rodriguez, Margarida Tomé & Eduardo González-Ferreiro (2016) Comparison of ALS based models for estimating aboveground biomass in three types of Mediterranean forest, European Journal of Remote Sensing, 49:1, 185-204
2279-7254
http://hdl.handle.net/10347/15865
10.5721/EuJRS20164911
Biomass components
Remote Sensing
Airborne laser scanning
Mediterranean Forest
Feature selection approaches
Comparison of ALS based models for estimating aboveground biomass in three types of Mediterranean forest
oai:minerva.usc.es:10347/167542022-02-11T11:25:30Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Arza García, Marcos
author
Gil Docampo, María de la Luz
author
Ortiz Sanz, Juan Pedro
author
Martínez-Rodríguez, Santiago
author
2018-03-01
The integration of local measurements and monitoring via global-scale Earth
observations has become a new challenge in digital Earth science. The increasing
accessibility and ease of use of virtual globes (VGs) represent primary advantages of
this integration, and the digital Earth scientific community has adopted this
technology as one of the main methods for disseminating the results of scientific
studies. In this study, the best VG software for the dissemination and analysis of
high-resolution UAV (Unmanned Aerial Vehicle) data is identified for global and
continuous geographic scope support. The VGs Google Earth and Sputnik
Geographic Information System (GIS) are selected and compared for this purpose.
Google Earth is a free platform and one of the most widely used VGs, and one of its
best features its ability to provide users with quality visual results. The proprietary
software Sputnik GIS more closely approximates the analytical capacity of a
traditional GIS and provides outstanding advantages, such as DEM overlapping and
visualization for its dissemination
Arza-García, M., Gil-Docampo, M., Ortiz-Sanz, J., & Martínez-Rodríguez, S. (2018). Virtual globes for UAV-based data integration: Sputnik GIS and Google Earth™ applications. International Journal of Digital Earth, 1-11
1753-8947
http://hdl.handle.net/10347/16754
10.1080/17538947.2018.1470205
2040-0934
Virtual Reality
Geospatial data
Geographic visualization
Multiscale
DEM
Virtual Globes for UAV-based data integration: Sputnik GIS and Google Earth™ applications
oai:minerva.usc.es:10347/166712023-07-10T06:12:26Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Moreno Fernández, Daniel
author
Álvarez González, Juan Gabriel
author
Rodríguez Soalleiro, Roque
author
Pasalodos Tato, María
author
Cañellas, Isabel
author
Montes, Fernando
author
Díaz Varela, Emilio Rafael
author
Sánchez González, Mariola
author
Crecente Campo, Felipe
author
Álvarez Álvarez, Pedro
author
Barrio Anta, Marcos
author
Pérez Cruzado, César
author
2018-05-15
Sustainable production of wood is one of the main services provided by forest systems. Site productivity in the case of forests is often evaluated through the site quality. However, most of the works addressing the site quality have been done at local or regional scale. In this work, we aim to develop site quality models for five dominant species in Spanish forests (Fagus sylvatica, Pinus pinaster atlantica, Quercus pyrenaica, Pinus nigra, Pinus sylvestris) and create site quality maps at a national-scale from these models. First, we develop site quality models using site form (height-diameter relationship) as the reference index and the Spanish National Forest Inventory as dataset. Then, we fit spatial additive models entering physiographic and climatic variables in order to predict the site quality over the whole country. Additionally, we plot site form maps for the five species in order to describe spatial pattern in site quality at a national scale. Altitude and aspect appeared to be fundamental variables in the assessment of site quality. The accuracy of the spatial additive models ranged from 38.2% to 47.9%. The correspondence between the predicted and observed maps of site qualities is clear. Our results provide a tool which could be used by forest managers in land use planning as well as in forest policy decision-making at a national scale. We suggest that this method could be used in other countries and that the maps could be expanded to the European scale to assessing the way in which site quality varies across Europe always considering that the relationships between forest productivity and environmental variables could vary among biogeoclimatic zones
Moreno-Fernández, D., Álvarez-González, J. G., Rodríguez-Soalleiro, R., Pasalodos-Tato, M., Cañellas, I., Montes, F., ... & Pérez-Cruzado, C. (2018). National-scale assessment of forest site productivity in Spain. Forest Ecology and Management, 417, 197-207. https://doi.org/10.1016/j.foreco.2018.03.016
0378-1127
http://hdl.handle.net/10347/16671
10.1016/j.foreco.2018.03.016
Uneven-aged stands
Height-diameter curves
Sustainable forest management
International forest policy
Guide curves
National-scale assessment of forest site productivity in Spain
oai:minerva.usc.es:10347/185472023-07-10T06:16:46Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2918com_10347_2891com_10347_18391com_10347_15468col_10347_10081col_10347_13951col_10347_18392
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Boubeta Martínez, Miguel
author
Lombardía Cortiña, María José
author
González Manteiga, Wenceslao
author
Marey Pérez, Manuel Francisco
author
2015
Wildfires are one of the main causes of forest destruction, especially in Galicia (north-west Spain), where the area burned by forest fires in spring and summer is quite high. This work uses two semiparametric time-series models to describe and predict the weekly burned area in a year: autoregressive moving average (ARMA) modelling after smoothing, and smoothing after ARMA modelling. These models can be described as a sum of a parametric component modelled by an autoregressive moving average process and a non-parametric one. To estimate the non-parametric component, local linear and kernel regression, B-splines and P-splines were considered. The methodology and software were applied to a real dataset of burned area in Galicia for the period 1999–2008. The burned area in Galicia increases strongly during summer periods. Forest managers are interested in predicting the burned area to manage resources more efficiently. The two semiparametric models are analysed and compared with a purely parametric model. In terms of error, the most successful results are provided by the first semiparametric time-series model
Boubeta, M., Lombardía, M., González-Manteiga, W., & Marey-Pérez, M. (2016). Burned area prediction with semiparametric models. International Journal Of Wildland Fire, 25(6), 669. doi: 10.1071/wf15125
1049-8001
http://hdl.handle.net/10347/18547
10.1071/WF15125
1448-5516
Bootstrap
Forest fires
Time series
Burned area prediction with semiparametric models
oai:minerva.usc.es:10347/312232024-02-26T09:13:49Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Fouz Varela, David Mateo
author
Carballo Sánchez, Rodrigo
author
López Moreira, Iván
author
González Vázquez, Xesús Pablo
author
Iglesias Rodríguez, Gregorio
author
2023-07-15
The cost-effective analysis (CEA) of hydrokinetic farms is typically based on simplistic assumptions regarding the performance and cost structure of hydrokinetic energy converters (HECs) and, in consequence, may lead to ill-informed decision-making. In this work, a novel approach to selecting the most appropriate combination of HEC and site within a coastal area is developed, with the accurate computation of the CEA parameters as the cornerstone. The approach, which is illustrated through a case study in the Shannon Estuary (W Ireland), encompasses four models, namely: (i) HEC-site selection model, (ii) energy production model, (iii) CAPEX model, and (iv) OPEX model. By avoiding simplistic assumptions, the proposed approach improves on current procedures and enables developers to accurately compute any cost-effective parameter of interest. In particular, operation and maintenance costs are considered, along with economies of scale, which are typically disregarded in existing procedures. Beyond the interest of the results of the Shannon case study, the approach can be implemented in other regions with potential for hydrokinetic energy conversion
Energy 282 (2023) 128373
0360-5442
http://hdl.handle.net/10347/31223
10.1016/j.energy.2023.128373
Tidal stream
Tidal energy
Marine renewable energy
Offshore renewable energy
Cost model
Energy production model
A methodology for cost-effective analysis of hydrokinetic energy projects
oai:minerva.usc.es:10347/218812020-04-30T02:01:27Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Fraguela Formoso, José Angel
author
Carral Couce, Luis
author
Iglesias Rodríguez, Gregorio
author
Castro Ponte, Alberte
author
Rodríguez Guerreiro, María Jesús
author
2011
El modelo empresarial surgido en los últimos años, necesita sistemas de gestión que permitan controlar de forma sistemática las actividades y procesos de la empresa, con la participación e implicación de todos sus trabajadores, con el objetivo de lograr los resul-tados previstos. En estos modelos de gestión, no basta con tener en cuenta solamente los parámetros económicos y de productividad. La satisfacción de los trabajadores, de los clientes y del entorno social en el que desarrolla su actividad, las actuales exigencias en materia de seguridad y salud en el trabajo, de la calidad y medioambientales, deben de ocupar posiciones preponderantes y de mejora continua
he entrepreneurial model that has arisen over the last years requires management systems that allow to control in a sys-tematic manner the activities and processes of the company, with the participation and implication of all its workers with the objective of achieving the intended goals. In these management models it is not suffi cient to take account of the economic and productivity param-eters. The satisfaction of workers, clients and the social environment in which the company operates, as well as the current requirements in terms of safety and health at work, of quality and environmental respect, all must be duly considered and continuously improved
Fraguela Formoso, J.A. et al. (2011). La integración de los sistemas de gestión. Necesidad de una nueva cultura empresarial."DYNA", Vol. 78, N. 167, p. 44-49
0012-7353
http://hdl.handle.net/10347/21881
2346-2183
Gestión
Seguridad
Calidad
Medioambiente
Management
Safety
Quality
Environment
La integración de los sistemas de gestión. Necesidad de una nueva cultura empresarial
oai:minerva.usc.es:10347/211302020-04-04T02:01:46Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Imaña Encinas, José
author
Antunes Santana, Otacílio
author
Riesco Muñoz, Guillermo
author
2019
1545 trees of Eucalyptus urophylla S.T. Blake were measured, felled and scaled with the purpose to select a wood
volume equation with one and two independent variables. The cross-validation sample was done in 310 trees.
The objective of this work was to select and to test tree stem volume equations with one and two independent
dendrometrical variables (breast height diameter and height) to be used in a Eucalyptus urophylla plantation
at the rotation age for firewood production. Selection criteria were the adjusted coefficient of determination,
estimated standard error, graphic distribution of waste and the Furnival index. From seven tested equations with
one dendrometrical variable, the Hohenadl-Krenn model (v=ß0+ß1
d+ß2
d2
) showed the highest statistical reliability
and it presented the best fit (R2
aj = 0.98, Sx = 0.06 e IF = 0.01), producing the regression equation: v = 21.5461 +
4.4448·d + 0.2247·d2
. From the other nine volume models that were considered, the two variable Meyer equation
(v=ß0+ß1
d+ß2
d2
+ß3dh+ß4d2
h+ß5h) presented the best fit, but lower than the Hohenadl-Krenn model.
Fueron medidos, apeados y troceados 1545 árboles
de Eucalyptus urophylla S.T. Blake con la finalidad de
seleccionar ecuaciones volumétricas con una y dos
variables independientes. La muestra de la validación
cruzada fue en 310 árboles. Fueron empleadas las
variables dendrométricas diámetro normal y altura
total del árbol para ajustar ecuaciones volumétricas
en una plantación de E. urophylla destinada a la
producción de leña y en edad de cosecha. Los criterios
de selección fueron los estadísticos: coeficiente de
determinación ajustado, error padrón de la estimación,
distribución gráfica de residuos e índice de Furnival.
De siete ecuaciones ensayadas con una variable
dendrométrica, la seleccionada fue la ecuación de
Hohenadl-Krenn (v=ß0+ß1
d+ß2
d2
), que obtuvo la
mayor fiabilidad estadística, presentando el mejor
ajuste (R2
aj = 0,98, Sx = 0,06 e IF = 0,01). Su expresión
matemática fue: v= 21,5461 + 4,4448∙d + 0,2247∙d2
. De
los nueve modelos ensayados que consideraron dos
variables dendrométricas la ecuación de Meyer log
v=ß0+ß1
d+ß2
d2
+ß3dh+ß4d2
h+ß5h presentó el mejor ajuste.
Sin embargo, en eficiencia fue inferior al compararla con
la ecuación de Hohenadl-Krenn.
Imaña-Encinas, J., Antunes-Santana, O., & Riesco-Muñoz, G. (2019). Selección de una ecuación volumétrica para Eucalyptus urophylla ST Blake en la región central del estado de Goiás, Brasil. Revista Forestal Mesoamericana Kurú, 16(39), 2-9.
2215-2504
http://hdl.handle.net/10347/21130
10.18845/rfmk.v16i39.4406
Forest mensuration
Dendrometrical variable
Regression analysis
Volume equation
Mensura forestal
Variable dendrométrica
Análisis de regresión
Tarifa de cubicación
Tarifa de ordenación
Selección de una ecuación volumétrica para Eucalyptus urophylla s.t. Blake en la región central del estado de Goiás, Brasil
oai:minerva.usc.es:10347/211292020-04-05T15:15:52Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Vilanova, Mar
author
Fandiño Beiro, María
author
Frutos Puerto, Samuel
author
Cancela Barrio, Javier José
author
2019
Vineyard management can influence the growth and yield components in the vineyards and therefore on the
grape and wine quality. In this work, a chemical study was conducted (2014–2015) to examine the effect of
fertigation on chemical composition of Albariño. A control (Rain-fed) and fertigation (60% and 100%) treatments were apply at same irrigation depth, where fertigation 100% is complete nutrient requirements to
Albariño trellis system in this location (Rias Baixas AOC, NW Spain).
Results showed that non-volatile compounds of Albariño musts were not affected by fertigation treatments.
However, the effect of fertigation treatments on the volatile composition was observed. Terpenes and C13-norisoprenids were the most affected families of volatile compounds by fertigation treatments, where 60% fertigation exhibited the highest concentration, improving the wine aroma quality. Application of principal component analysis (PCA) showed a good separation of Albariño grape according to fertigation treatments and
vintages.
Vilanova, M., Fandiño, M., Frutos-Puerto, S., & Cancela, J. J. (2019). Assessment fertigation effects on chemical composition of Vitis vinifera L. cv. Albariño. Food chemistry, 278, 636-643.
0308-8146
http://hdl.handle.net/10347/21129
10.1016/j.foodchem.2018.11.105
1873-7072
Nutrition grapevine
Aroma compounds
Irrigation
Volatiles
No-volatiles
Assessment fertigation effects on chemical composition of Vitis vinifera L. cv. Albarino
oai:minerva.usc.es:10347/242762023-07-10T06:21:40Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Siqueira, Glécio Machado
author
Dafonte Dafonte, Jorge
author
Vidal Vázquez, Eva
author
Válcarcel Armesto, Montserrat
author
2012
O objetivo deste trabalho foi avaliar a distribuição espacial da rugosidade do solo em microparcelas compostas por diferentes solos de Galícia (Espanha) após aplicação de distintas chuvas simuladas. Os agregados do solo, de 3-5 cm, foram coletados nos municípios de Lugo e Taboada. Em laboratório as parcelas experimentais foram construídas utilizando-se base metálica móvel de 0,86 m x 0,86 m (0,73 m2). A rugosidade do solo (dm) foi determinada com rugosímetro laser, antes e depois da aplicação de quantidades crescentes de chuva simulada (50 mm h-1 e 75 mm h-1) durante uma hora. O índice de rugosidade aleatória (RR) cresceu com o aumento do volume de chuva simulada no solo franco (Taboada). Todos os tratamentos estudados apresentaram alta razão de dependência espacial entre amostras (RD) em função do grande número de leituras fornecidas pelo rugosímetro laser, que favorece uma minimização da variabilidade ao acaso
The objective of this study was to evaluate the spatial distribution of soil roughness in microplots composed of different soils in Galicia (Spain) after application of different simulated rainfall. Clusters of 3-5 cm soil were collected in the municipalities of Lugo and Taboada. In the laboratory experimental plots were built using metallic mobile 0.86 m x 0.86 m (0.73 m2). The roughness of the soil (dm) was determined with laser reliefmeter before and after application of different amounts of rain (50 mm h-1 and 75 mm h-1) for an hour. The index of random roughness (RR) increased with increasing the volume of simulated rain in loam soil (Taboada). All treatments studied showed a high rate of spatial dependence between samples (RD), depending on the number of readings provided by laser reliefmeter, which favors a minimization of random variability
1981-1160
http://hdl.handle.net/10347/24276
10.5039/agraria.v7i4a1783
1981-0997
Geoestatística
Manejo do solo
Erosão hídrica
Agregação do solo
Geostatistics
Soil tillage
Water erosion
Soil aggregation
Distribuição espacial da rugosidade do solo em microparcelas experimentais sob diferentes intensidades de chuva simulada
oai:minerva.usc.es:10347/200062020-01-31T15:00:24Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Fernández Parajes, José
author
Riesco Muñoz, Guillermo
author
2016
Se describe la comunidad de peces del río Masma y sus principales afluentes a partir del inventario demográfico de las especies (trucha común y reo, anguila, salmón atlántico, lamprea, platija y mugílidos) y a partir del análisis del hábitat (calidad del agua, morfometría del cauce, vegetación y presión pesquera). Se realizaron 22 estaciones de muestreo por pesca eléctrica durante tres años. Los resultados informan de un hábitat de buena calidad para los salmónidos, levemente alterado por la acción humana y con una abundancia de peces intermedia (densidad: 3 847 ind/ha; biomasa: 127.1 kg/ha), con existencias y producciones mucho más altas en los afluentes que en el curso principal.
La especie más abundante fue la trucha común (68% de los ejemplares de la muestra), escaseando los individuos de las clases de edad superiores a 4+. Se concluye que el
origen del desequilibrio demográfico que se detecta está en la elevada presión de los pescadores tanto en tramos libres como en vedados y acotados. La alta presión pesquera sobre la trucha común es en parte atribuible a que la talla mínima pescable que se aplica en la zona incluye clases de edad no reproductivas (1+). Se expone una propuesta de mejora de la gestión basada en conservar el hábitat en su estado actual, junto con el cambio de las tallas mínimas de captura y la reubicación de las zonas de pesca, con objeto de favorecer
la regeneración natural de las poblaciones de salmónidos y lograr a medio plazo estabilizar las clases de edad
The fish populations in the Masma River and its main affluents were described on the basis of the study of the demographic characteristics of the species (brown trout, European eel, Atlantic salmon, sea lamprey, European flounder and Mugilidae) and the habitat analysis (water quality, morphometry of the river bed, vegetation and fishing effort). An electrofishing survey was carried out in 22 sampling points during three years. The expected high quality of the habitat for salmonids was shown in a slightly altered environment (intermediate stocks, 3 847 ind/ha, 127.1 kg/ha), being the abundances and productions much higher in the affluents than in the main river. Brown trout was the most abundant species (68 % of the individuals of the sample), with low presence of individuals
of age 4+ and upper classes. The unbalanced age distribution is originated by the overfishing pressure in the area. The high fishing pressure on brown trout is partly attributable to the fishing minimum size, that encompasses non reproductive classes (1+). A
management improvement is proposed, based on the preservation of the current state of the habitat, changes in the minimum catching length and relocation of fishing areas, to achieve and enhance natural regeneration of salmonids and to stabilize age classes in the medium term
Fernández-Parajes, J., & Riesco-Muñoz, G. (2016). Poblaciones de peces del río Masma y afluentes (España). Propuestas de gestión. Tecnología y ciencias del agua, 7(3), 37-52
2007-2422
http://hdl.handle.net/10347/20006
0187-8336
Anguilla anguilla
Galicia
Gestión de pesquerías
Inventario de peces
Mugilidae
Petromyzon marinus
Platichthys flesus
Salmo salar
Salmo trutta
Fisheries management
Fisheries inventory
Poblaciones de peces del río Masma y afluentes (España). Propuestas de gestión
oai:minerva.usc.es:10347/286672022-11-23T12:32:25Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Ortiz Sanz, Juan Pedro
author
Gil Docampo, María de la Luz
author
Rego Sanmartín, María Teresa
author
Arza García, Marcos
author
Tucci, G.
author
Parisi, E. I.
author
Bonora, V.
author
Mugnai, Francesco
author
2020
The advent of the smartphones brought with them higher processing capabilities and improved camera specifications which boosted the applications of mobile-based imagery in a range of domains. One of them is the 3-D reconstruction of objects by means of photogrammetry, which now enjoys great popularity. This fact brings potential opportunities to develop educational procedures in high schools using smartphone-based 3-D scanning techniques. On this basis, we designed a Project Based e-Learning (PBeL) initiative to introduce secondary students to the disciplines of photogrammetry through the use of their mobile phones in an attractive and challenging way for them. The paper describes the motivation behind the project "D3MOBILE Metrology World League", supported by ISPRS as part of the "Educational and Capacity Building Initiative 2020"programme. With this Science, Technology, Engineering and Mathematics (STEM) initiative, we implement a methodology with the format of an international competition, that can be adapted to daily classwork at the high school level anywhere in the world. Therefore, the championship is essentially structured around a collection of well-thought-out e-learning materials (text guidelines, video tutorials, proposed exercises, etc.), providing a more flexible access to content and instruction at any time and from any place. The methodology allows students to gain spatial skills and to practice other transversal abilities, learn the basics of photogrammetric techniques and workflows, gain experience in the 3-D modelling of simple objects and practice a range of techniques related to the science of measurement
Ortiz-Sanz, J. P., Gil-Docampo, M., Rego-Sanmartín, T., Arza-García, M., Tucci, G., Parisi, E. I., ... & Mugnai, F. (2020). D3mobile metrology world league: training secondary students on smartphone-based photogrammetry. The International Archives of Photogrammetry, Remote Sensing and Spatial Information Sciences, 43, 235-241.
1682-1750
http://hdl.handle.net/10347/28667
10.5194/isprs-archives-XLIII-B5-2020-235-2020
3-D Scanning
Challenges
Education
Free apps
Mobile phones
STEM
D3Mobile metrology world league: training secondary students on smartphone-based photogrammetry
oai:minerva.usc.es:10347/176092020-10-22T12:33:32Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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García-Montiel, Emily
author
Cubbage, Frederick
author
Rojo Alboreca, Alberto
author
Lujan-Álvarez, Concepción
author
Montiel-Antuna, Eusebio
author
Corral-Rivas, José Javier
author
2017
Mexico has had a non-state forest certification system under the Forest Stewardship Council
(FSC) since it was initiated in 1993, and developed a new state-sponsored Mexican Forest Certification System (MFCS) that began in 2008. Several analyses have been made of FSC forest certification in Mexico, but none have summarized the new MFCS system or compared its standards with FSC. We compare the implementation of the non-state FSC market forest certification with the state-sponsored MFCS system in Mexico, and review literature on forest certification, focusing on all studies in Mexico. MFCS has had substantial enrollment of more than 902,802 ha by 2016, compared to 900,388 ha for the more-established FSC program. MFCS can be acceptable for stand-alone forest certification, and might be viewed as a stepwise path to FSC certification. The merits of both systems are analyzed in terms of standard content, likely sustainable forestry practices, access to markets, and community
forestry enterprises.
García-Montiel, E.; Cubbage, F.; Rojo-Alboreca, A.; Lujan-Álvarez, C.; Montiel-Antuna, E.; Corral-Rivas, J.J. An Analysis of Non-State and State Approaches for Forest Certification in Mexico. Forests 2017, 8, 290
1999-4907
http://hdl.handle.net/10347/17609
10.3390/f8080290
State and non-state forest certification systems
FSC
MFCS
NMX-143
An Analysis of Non-State and State Approaches for Forest Certification in Mexico
oai:minerva.usc.es:10347/261382021-05-08T02:04:52Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Sinde González, Ízar
author
Gil Docampo, María de la Luz
author
Arza García, Marcos
author
Grefa Sánchez, José
author
Yánez Simba, Diana
author
Pérez, Patricio
author
Abril Porras, Víctor Hugo
author
2021
Pastures account for more than 56% of the total agricultural area of Ecuador and constitute the main food source for livestock. Hence, the agile, affordable, and reliable quantification of aboveground biomass (AGB) is an essential task in grazing utilization and management. In this paper, a method to estimate the AGB via aerial photogrammetry with a low-cost UAV multirotor is proposed. Digital terrain models and crop surface models were generated from data captured during two flights at different times, and the volume between them was calculated. An empirical relationship between volume and dry biomass was obtained by harvesting and weighing some samples and deriving a density factor (DF). The method was tested over 54 plots with different types of forage under differential fertilization treatments. Fertilized annual ryegrass exhibited the best growth and highest biomass (2632 kg/ha). The estimation and calculation of the crop volume via UAV-based photogrammetry saves time and generates notably precise (R2 = 0.78) information on the dry biomass
International Journal of Applied Earth Observation and Geoinformation, 101 (2021), 102355
0303-2434
http://hdl.handle.net/10347/26138
10.1016/j.jag.2021.102355
Cultivated pastures
CSM
Precision agriculture
DTM
Aboveground biomass
Biomass estimation of pasture plots with multitemporal UAV-based photogrammetric surveys
oai:minerva.usc.es:10347/306222023-05-31T02:03:14Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Tafur, Nestor
author
Somoza Cerviño, Alba
author
Pérez Muñuzuri, Alberto
author
Rodriguez Cabo, Borja
author
Barrio Iribarren, Izaskun
author
Panadero Ruiz, Asier
author
García Mayoral, M. Flor
author
Soto Campos, Ana María
author
2023
This study aims to assess a surfactant blend for enhanced oil recovery from carbonate rocks. Due to the abundance of these reservoirs, their profitable exploitation would ensure our petrochemical needs are met, and maintain current quality of life. The objective of this work is to increase the technology readiness level of our previous proposal based on the use of a blend of pure sodium dodecylbenzene sulfonate and the surface-active ionic liquid cocosalkylpentaethoximethyl ammonium methylsulfate. To that aim, the method was adapted for its application with a commercially available petrochemical surfactant (RECOLAS103, a mixture of lineal alkyl benzene sulfonates), and reservoir simulations were carried out to evaluate its effectiveness. Phase behavior, stability, dynamic interfacial tension, adsorption and core flooding were the experimental tests carried out. An optimized formulation consisting of 1 wt% of blend (40 wt% RECOLAS103) in synthetic sea water was found stable and able to reduce water-oil interfacial tension down to 0.02 mN/m. The dynamic blend adsorption in carbonate rocks was found to be 0.60 mg/grock, a promising value for the application. Core flooding tests were conducted at 25 and 120 °C and additional oil recoveries achieved ranged from 10.2 to 12.7% of the original oil in place, the lowest production obtained at the highest temperature. This work offers an advance in the application of surfactants for EOR in carbonate reservoirs, since it improves previous proposals that show stability or high adsorption problems. Moreover, a chemical injection optimization was also carried out by simulation with the CMG-STARS software. Results point to the possibility of reaching higher oil recoveries than those obtained experimentally if the extraction method is optimized
Geoenergy Science and Engineering 224 (2023) 211619
http://hdl.handle.net/10347/30622
10.1016/j.geoen.2023.211619
2949-8910
Blend
Microemulsion
Flooding
History match
Assessment of a surface-active ionic liquid formulation for EOR applications: Experimental and simulation studies
oai:minerva.usc.es:10347/223632020-05-16T02:01:35Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Bouzas Cid, Yolanda
author
Trigo Córdoba, Emiliano
author
Orriols, Ignacio
author
Falqué, Elena
author
Mirás Avalos, José Manuel
author
2018
Adopting cover crops for vineyard soil management can provide several benefits, including soil protection, reductions in vine vigor, and enhancements in berry composition. However, the effects of this practice on wine aroma have seldom been addressed. This study aimed to determine the influence of different cover crops and soil tillage on the must and wine amino acid composition and wine volatile compounds of the red cultivar, ‘Mencía’ (Vitis vinifera L.), grown in Northwest Spain. Treatments consisted of soil tillage (ST), native vegetation (NV), English ryegrass (ER), and subterranean clover (SC). Cover crops did not alter the macro-constituents of musts; however, musts from NV and SC tended to lower concentrations of amino acids. Some color attributes of wines were influenced by cover crops in the vineyard. Methanol and trans-linalool oxide (pyran) concentrations in wines were significantly affected by soil management. Professional tasters encountered differences in visual, aroma, and palate descriptors of wines depending on the treatment imposed in the vineyard. These alterations in sensory properties seemed to obey to slight modifications of wine chemical characteristics due to vineyard soil management. According to these results, cover crops might be useful for modulating wine aroma in humid climates
Bouzas-Cid, Y.; Trigo-Córdoba, E.; Orriols, I.; Falqué, E.; Mirás-Avalos, J.M. Influence of Soil Management on the Red Grapevine (Vitis vinifera L.) Mencía Must Amino Acid Composition and Wine Volatile and Sensory Profiles in a Humid Region. Beverages 2018, 4, 76
http://hdl.handle.net/10347/22363
10.3390/beverages4040076
2073-445x
Nitrogen fraction
Red wine
Sensory profile
Soil management
Tillage
Volatile compounds
Influence of soil management on the red grapevine (vitis vinifera L.) mencía must amino acid composition and wine volatile and sensory profiles in a humid region
oai:minerva.usc.es:10347/196932020-01-31T08:31:54Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_8426com_10347_250com_10347_2956col_10347_10081col_10347_18919col_10347_9747
00925njm 22002777a 4500
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Marey Pérez, Manuel Francisco
author
Rodríguez Vicente, Verónica
author
Crecente Maseda, Rafael
author
2007
O monte arborado en Galicia experimentou un auxe significativo nas últimas décadas
tanto en superficie coma en valor económico. Este desenvolvemento forestal foi obxecto de importantes
publicacións centradas, principalmente, en inventarios ou en censos relativos á produción
e subministración da madeira. Porén, as condicións nas que se asenta este éxito non
están tan amplamente documentadas, isto é, a estrutura da propiedade forestal e o perfil do seu
xestor son practicamente tópicos descoñecidos. Partindo desta premisa, coñecer os factores
que determinan o comportamento forestal é a base para comprender este auxe e, deste modo,
proxectar a súa futura tendencia e planificar medidas públicas de apoio. Este traballo forma parte
dunha liña de investigación máis ampla para o desenvolvemento dun modelo metodolóxico
de análise e estudo dos propietarios forestais galegos. Preséntanse os resultados obtidos dun
cuestionario persoal a 103 propietarios titulares catastrais con máis de 1 hectárea de superficie
forestal produtora no municipio de Barreiros, no nordeste da provincia de Lugo, nun intento por
caracterizar a propiedade individual e por comprender a conduta forestal do xestor. A análise
expón que esta actividade pode ser unha ocupación económica interesante, aínda que actualmente
non se practica como tal. Considerando o éxito parcial de medidas públicas exclusivamente
agrarias ou forestais, asegurar o futuro da pequena propiedade requirirá ferramentas ou
programas públicos orientados a integrar o conxunto de producións tradicionais da explotación
familiar. Dese modo, poderase incentivar a continuidade xeracional da explotación mediante a
práctica forestal e agrogandeira
El monte arbolado en Galicia ha experimentado un auge significativo en las últimas décadas tanto en superficie como en valor económico. Este desarrollo forestal ha sido objeto de importantes publicaciones centradas, principalmente, en inventarios o en censos relativos a la producción y suministro da madera. Sin embargo, las condiciones en las que se asienta este éxito no están tan ampliamente documentadas, esto es, la estructura de la propiedad forestal y el perfil de su gestor son prácticamente tópicos desconocidos. Partiendo de esta premisa, conocer los factores que determinan el comportamiento forestal es la base para comprender este auge y, de ese modo, proyectar su futura tendencia y planificar medidas públicas de apoyo. Este trabajo forma parte de una línea de investigación más amplia para el desarrollo de un modelo metodológico de análisis y estudio de los propietarios forestales gallegos. Se presentan los resultados obtenidos de un cuestionario personal a 103 propietarios titulares catastrales con más de 1 hectárea de superficie forestal productora en el municipio de Barreiros, en el nordeste de la provincia de Lugo, en un intento por caracterizar la propiedad individual y por comprender la conducta forestal del gestor. El análisis expone que esta actividad puede ser una ocupación económica interesante, aunque actualmente no se practica como tal. Considerando el éxito parcial de medidas públicas exclusivamente agrarias o forestales, asegurar el futuro de la pequeña propiedad requerirá herramientas o programas públicos orientados a integrar el conjunto de producciones tradicionales de la explotación familiar. De ese modo, se podrá incentivar la continuidad generacional de la explotación mediante la práctica forestal y agroganadera
Woodlands have expanded greatly in Galicia during the last few decades, in terms of
forest area and economic value. This forest development has been broadly documented on inventories
and census related with the forest production and timber supply. Nevertheless, the circumstances
which support this success are not so studied, this is, the forest holding structure
and its owner profile are practically unknown. With this premise, knowing the issues that determinate
the forest behaviour is the basis to understand this forest success and, therefore, to simulate
the future subsector evolution that allows to plan public measures of supporting. This paper
is part of a broader study, which develops a new methodology for surveying and characterising
private forest owners in Galicia. Here, we present results from a questionnaire survey carried
out with a total of 103 landowners who had over 1 ha of productive forest land in the Barreiros
municipality, located in Northern of Lugo province, with the aim of characterizing the individual
property and understanding the owners’ decision-making in forestry. The analysis shows that
forestry can be an interesting economic activity, although it is not seen as such today. Take into
account the partial success of measures exclusively forest or agrarian, to ensure the future of
Galician property will necessitate public tools or programmes orientated to integrate the set of
agroforestry activities on family farm. Therefore, it will motivate the generational continuity of the
farm by means of agroforestry practices
Revista Galega de Economía, vol. 16, núm. 1 (2007), pp. 47-70 ISSN 1132-2799
1132-2799
http://hdl.handle.net/10347/19693
2255-5951
Economía forestal
Xestión forestal individual
Propietario forestal individual
Usos do solo
Gestión forestal individual
Usos del suelo
Forest economy
Land uses
Individual forest owner
Small-scale forestry
Perfil do propietario forestal individual en Galicia: obxectivos e prácticas de xestión no nordeste da Comunidade
oai:minerva.usc.es:10347/226962020-05-30T02:01:01Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Díaz Maroto, Ignacio Javier
author
Fernández Parajes, José
author
Vila Lameiro, Pablo
author
Barcala Pérez, Eva
author
2010
Data from stem analysis of 56 dominant trees of Quercus pyrenaica Willd., in natural stands in Galicia (NW
Iberian Peninsula), were used to evaluate four dynamic site equations derived with the Generalized Algebraic
Difference Approach (GADA). All the equations are base-age invariant and directly estimate height and site
index from any height and age. The fittings were made using a data structure involving all possible growth
intervals. The GADA formulation derived on the basis of the Bertalanffy-Richards model by considering the
asymptote and the initial pattern parameters as related to site productivity. It is therefore recommended for
height growth prediction and site classification for natural stands of rebollo oak in Galicia. The autocorrelation
was analyzed with a test of residuals using Durbin’s t-test without reaching a manifest result of autocorrelation
between managed data
Dados da análise de tronco de 56 árvores dominantes de Quercus pyrenaica Willd. de florestas
naturais da Galicia (NW Península Ibérica) foram utilizados para avaliar quatro equações dinamicas
de índice de sitio obtidas com a Abordagem Generalizada de Diferença Algébrica (GADA). Todas as
equações são baseadas na idade invariante e diretamente estimam a altura e o índice de sitio. Os
ajustes foram feitos utilizando uma estrutura de dados que incluiam todos os possíveis intervalos de
crescimento. A formulação GADA teve base no modelo Bertalanffy-Richards, considerando a assíntota
e do padrão inicial como parâmetros relacionados à produtividade do sitio. Assim, recomenda-se o
modelo na previsão do crescimento em altura e classificação de sitios para povoamentos naturais de
carvalho negro na Galicia. A autocorrelação foi analisada com um teste de resíduos utilizando Durbin’s
t-teste, sem chegar a um resultado significativo de autocorrelação entre os dados.
Díaz-Maroto, I. J., Fernández-Parajes, J., Vila-Lameiro, P., & Barcala-Pérez, E. (2010). Site index model for natural stands of rebollo oak (Quercus pyrenaica Willd.) in Galicia, NW Iberian Peninsula. Ciência Florestal, 20(1), 57-68.
0103-9954
http://hdl.handle.net/10347/22696
10.5902/198050981761
1980-5098
Quercus pyrenaica
Site index model
Height growth
Generalized Algebraic Difference Approach
Quercus pyrenaica
Modelo de índice de sitio
Crescimento em altura
Abordagem das Diferenças Algébricas Generalizadas
Site index model for natural stands of rebollo oak (Quercus pyrenaica Willd.) In Galicia, NW Iberian Peninsula
oai:minerva.usc.es:10347/209222023-07-10T06:13:05Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_9747col_10347_15615
00925njm 22002777a 4500
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Moreno Fernández, Daniel
author
Álvarez González, Juan Gabriel
author
Rodríguez Soalleiro, Roque
author
Cañellas, Isabel
author
Montes, Fernando
author
Pérez Cruzado, César
author
2018
La determinación de la calidad de estación de un rodal es fundamental para poder establecer una gestión sostenible de los recursos. La mayor parte de los trabajos que estudian las variables que explican la calidad de estación se ha llevado a cabo a escala local o regional y fundamentalmente utilizando índices, como el índice de sitio (relación altura dominante-edad), aplicables únicamente a masas regulares. Los objetivos de este trabajo son: i) ajustar modelos de calidad de estación a escala nacional para algunas de las principales especies arbóreas forestales de la Península Ibérica (Pinus sylvestris, P. nigra, P. pinaster, Fagus sylvatica y Quercus pyrenaica) válidos para masas con distinta forma principal; y ii) elaborar mapas de calidad de estación a escala nacional. Los modelos de calidad de estación se ajustaron usando modelos no lineales a partir de los pares de datos altura dominante-diámetro dominante de las parcelas del Tercer Inventario Forestal Nacional. Los mapas de calidad de estación se desarrollaron usando las predicciones de modelos aditivos espaciales que incluían variables fisiográficas como predictores. La precisión de nuestros modelos aditivos espaciales se encuentra entre 38,2 % y 47,9 %. La altitud y la orientación son variables fundamentales para determinar la calidad de estación. Los mapas mostrados pueden ser útiles tanto para la gestión forestal a escala regional como para el desarrollo de políticas forestales a nivel nacional
Moreno Fernández, D., Álvarez Álvarez, J.G., Rodríguez Soalleiro, R., Cañellas, I. y Pérez Cruzado, C. (2018). Mapas nacionales de calidad de estación para Pinus sylvestris, Pinus nigra, Pinus pinaster, Fagus sylvatica y Quercus pyrenaica. Foresta, nº 71, p. 50-57
1575-2356
http://hdl.handle.net/10347/20922
Gestión forestal sostenible
Índice de forma
Políticas forestales
Escala nacional
Mapas nacionales de calidad de estación para Pinus sylvestris, Pinus nigra, Pinus pinaster, Fagus sylvatica y Quercus pyrenaica
oai:minerva.usc.es:10347/267552023-07-10T06:11:38Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
González Rodríguez, Miguel Ángel
author
Diéguez Aranda, Ulises
author
2021
As climate change makes many traditional empirical growth approaches not functional for forest dynamics modelling, new climate-sensitive models are needed. However, using these newly developed models for extrapolation, such as predicting forest productivity for new areas or future scenarios is still a difficult task. In this study, we proposed a method for delimiting the uncertainty of climate-sensitive extrapolations of forest productivity (site index, ) using the regularisation approach implicit in distance-based Support Vector Regression. As a case study, we predicted forest productivity with a dataset of 165 permanent research plots of radiata pine forests in Galicia (NW of Spain) as a function of bioclimatic variables from the Worldclim 2 raster datasets. The developed model was based on the radial basis kernel and, after calibrating it using cross-validation, produced adequate performance metrics, explaining up to 56% of the site index’ variability. Then, we predicted forest productivity for the Galician territory basing on climate raster maps for current conditions and six future scenarios (using different Global Climate Models) and evaluated the resulting maps by delimiting the surfaces with predictions strongly regressed to the mean. This analysis revealed that the extrapolations for unseen climatic conditions were extremely regularised, even for current climate, being 60–99% of the territory regressed to the observational site index mean. In other words, the validity area delimited for the fitted model was narrow in comparison with the prediction extent. These results imply that the climatic conditions in these areas/scenarios were too different from the training datastet for making reliable predictions, at least under the optimum model setup defined by cross-validation. However, when we reduced the parameter, responsible for controlling distance-based regularisation, we observed a noticeable increase in validity area of the model, together with a drop in performance. This fact revealed the existence of a trade–off between highly specific models, with high performance and a small applicability area, and more generalisable models, with a broad validity area but lower performance. We concluded that the tested methodology could be a useful starting point for assessing the spatio-temporal uncertainty of forest productivity predictions in the future
Ecological Indicators 2021, 128: 107820. https://doi.org/10.1016/j.ecolind.2021.107820
1470-160X
http://hdl.handle.net/10347/26755
10.1016/j.ecolind.2021.107820
Pinus radiata
Site index
Extrapolation
Machine learning
Climate change
Forest growth
Delimiting the spatio-temporal uncertainty of climate-sensitive forest productivity projections using Support Vector Regression
oai:minerva.usc.es:10347/162462020-01-31T11:51:42Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Hevia Cabal, Andrea
author
Álvarez González, Juan Gabriel
author
Ruiz Fernández, Eduardo
author
Prendes, C.
author
Ruiz González, Ana Daría
author
Majada, J.
author
González Ferreiro, Eduardo Manuel
author
2016
Forest fires are a major threat in NW Spain. The importance and frequency of these events in the area suggests the need for fuel management programs to reduce the spread and severity of forest fires. Thinning treatments can contribute for fire risk reduction, because they cut off the horizontal continuity of forest fuels. Besides, it is necessary to conduct a fire risk management based on the knowledge of fuel allocation, since fire behaviour and fire spread study is dependent on the spatial factor. Therefore, mapping fuel for different silvicultural scenarios is essential. Modelling forest variables and forest structure parameters from LiDAR technology is the starting point for developing spatially-explicit maps. This is essential in the generation of fuel maps since field measurements of canopy fuel variables is not feasible. In the present study, we evaluated the potential of LiDAR technology to estimate canopy fuel variables and other stand variables, as well as to identify structural differences between silvicultural managed and unmanaged P. pinaster Ait. stands. Independent variables (LiDAR metrics) of greater explanatory significance were identified and regression analyses indicated strong relationships between those and field-derived variables (R2 varied between 0.86 and 0.97). Significant differences were found in some LiDAR metrics when compared thinned and unthinned stands. Results showed that LiDAR technology allows to model canopy fuel and stand variables with high precision in this species, and provides useful information for identifying areas with and without silvicultural management
Los incendios forestales suponen una gran amenaza en el NO de España. La importancia y frecuencia de estos eventos en la zona sugiere la necesidad de programas de gestión del combustible para reducir la propagación y severidad de los incendios. La realización de una selvicultura de claras puede contribuir a la reducción del riesgo de incendio, ya que ocasiona una ruptura de la continuidad horizontal del combustible forestal. Además, es necesario realizar una gestión del riesgo de incendio basada en el conocimiento de la localización del combustible sobre el terreno, puesto que el estudio del comportamiento de un incendio y la simulación de la propagación del fuego son dependientes del factor espacial. Por ello, resulta esencial la generación de mapas del combustible para diferentes escenarios selvícolas. La elaboración de modelos de estimación de variables dasométricas y de estructura de la masa a partir de tecnología LiDAR es el punto de inicio para la elaboración de una cartografía espacialmente explícita. Esto adquiere mayor valor en los mapas de combustible puesto que la medición de las variables en campo resulta inviable. En el presente estudio, evaluamos el potencial de la tecnología LiDAR para estimar variables del combustible de copa y otras variables de masa, así como para identificar diferencias estructurales a nivel de rodal en masas de Pinus pinasterAit. con y sin manejo selvícola. Las variables independientes (métricas LiDAR) de mayor importancia explicativa fueron identificadas y los análisis de regresión indicaron fuertes relaciones entre éstas y las variables medidas en campo (R2 varió entre 0.86 y 0.97). Por otra parte, se observaron diferencias significativas en algunas métricas LiDAR cuando se compararon masas aclaradas y no aclaradas. Los resultados demostraron que la tecnología LiDAR permite la modelización de variables de masa y de combustible de copa con alta precisión en esta especie, y que proporciona información útil para la identificación de áreas con y sin gestión selvícola
Hevia, A., Álvarez-González, J., Ruiz-Fernández, E., Prendes, C., Ruiz-González, A., Majada, J., & González-Ferreiro, E. (2016). Modelling canopy fuel and forest stand variables and characterizing the influence of thinning in the stand structure using airborne LiDAR. Revista de Teledetección, 0(45), 41-55. doi:https://doi.org/10.4995/raet.2016.3979
1133-0953
http://hdl.handle.net/10347/16246
10.4995/raet.2016.3979
1988-8740
Pinus pinaster
Airborne Laser Scanning (ALS)
Fuel management
Canopy fuel load
Canopy bulk density
Canopy base height
Láser escáner aéreo
Gestión del combustible
Carga de combustible
Densidad aparente de copa
Altura de la base de la copa
Modelling canopy fuel and forest stand variables and characterizing the influence of thinning in the stand structure using airborne LiDAR
oai:minerva.usc.es:10347/148302023-07-10T06:16:26Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Rojo Alboreca, Alberto
author
García Villabrille, Juan Daniel
author
Pérez Rodríguez, Fernando
author
2016
EucaTool® es una aplicación gratuita de software “en la nube” que ha sido desarrollada para estimar el crecimiento
y la producción de plantaciones de brinzales y clonales de eucalipto (Eucalyptus globulus Labill.) de primer turno en Galicia. La aplicación se ha diseñado para poner a disposición de propietarios, empresas y gestores forestales la posibilidad de calcular de forma muy sencilla el volumen y la biomasa de dichas plantaciones a partir de datos de árboles individuales o de datos de rodal, así como una estimación de su crecimiento y producción futura (indicando la edad óptima de corta por máxima renta en especie) a partir de la medición
de solamente cuatro variables medias del rodal: edad, número de árboles por hectárea, altura dominante y área basimétrica. EucaTool® implementa un modelo dinámico de crecimiento y producción válido para plantaciones clonales y no clonales de primer turno de la especie en la región y que integra diferentes módulos o funciones de transición para la altura dominante (curvas de calidad de la estación), número de pies por hectárea (función de mortalidad) y área basimétrica, junto con ecuaciones o tarifas de cubicación y de biomasa. Puede accederse a EucaTool® desde cualquier dispositivo con conexión a internet desde la dirección:
http://app.eucatool.com Además, toda la información relativa al uso de la aplicación está publicada en una web
ligada al aplicativo: http://www.eucatool.com
Rojo-Alboreca, A., García-Villabrille, J.D., Pérez-Rodríguez, F. (2016). EucaTool®: aplicación web para estimar el crecimiento y la producción de plantaciones de Eucalyptus globulus Labill. en Galicia. "Cuad. Soc. Esp. Cienc. For.", vol. 42, 191-200
1575-2410
http://hdl.handle.net/10347/14830
Biomasa
Brinzal
Clon
Eucalipto azul
EucaTool®: aplicación web para estimar el crecimiento y la producción de plantaciones de Eucalyptus globulus Labill. en Galicia
oai:minerva.usc.es:10347/240042021-01-09T03:08:05Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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García Lamparte, Andrés Manuel
author
Santé Riveira, Inés
author
Loureiro Veira, Xurxo
author
Miranda Barrós, David
author
2020
Green infrastructure has acquired greater importance in recent years in relation to climate change adaptation. Green infrastructure planning has been identified as a new and innovative means of land planning that can contribute to preventing the impacts of climate change. However, this has been explored more thoroughly in urban areas than at the regional scale. The present study proposes a methodology including multi-criteria evaluation techniques for assessing the ESS involved in the fight against climate change and for the spatial planning of multifunctional green infrastructure areas based on the results of this assessment. Application of the methodology for green infrastructure planning aimed at confronting climate change at landscape level in the region of Galicia (NW Spain) successfully delimited multifunctional green infrastructure zones. Results show that delimited zones have a higher provision potential for more ESS than protected natural areas and areas that are not part of the green infrastructure
García, A.M.; Santé, I.; Loureiro, X.; Miranda, D. Spatial Planning of Green Infrastructure for Mitigation and Adaptation to Climate Change at a Regional Scale. Sustainability 2020, 12, 10525
http://hdl.handle.net/10347/24004
10.3390/su122410525
2071-1050
Green infrastructure delineation
Green infrastructure zoning
Multi-criteria evaluation
Multifunctional green infrastructure
Climate change
Spatial Planning of Green Infrastructure for Mitigation and Adaptation to Climate Change at a Regional Scale
oai:minerva.usc.es:10347/322732024-02-03T01:03:28Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Álvarez-Feal, Carlos
author
Rodrígue-Guerreiro, Mª Jesús
author
Vargas, Andreina
author
Carballo, Rodrigo
author
Carral, Luis
author
Areán, Néstor
author
2019
The Galician coast, and particularly its estuaries are ecosystems with a large biological production which require protection against the strong human pressure they suffer. Sustainability in fishing, shell fishing and recreational activities makes it advisable to develop measures such as the implementation of green artificial reefs (AR), which promote wealth and biodiversity in areas that stand out due to their productive capacity.
This document proposes a database management system (DBMS) to determine the position of the AR groups, based on geographic information systems (GIS) combined with high resolution numerical modelling and the development of computational algorithms. This system will be capable of analysing a large amount of spatial information regarding socio-economic and environmental factors that affect their installation.
The methodology considered in the DBMS takes into account production factors and economic factors related to construction and maintenance. This combination allows for the identification of the best locations for the functional development of the AR group with low implementation costs. The DBMS is applied to the Ria of Ares-Betanzos leading to the definition of the most suitable places for installing AR groups in this area.
Luis Carral, Carlos Alvarez-Feal, M. Jesús Rodríguez-Guerreiro, Andreina Vargas, Néstor Arean, Rodrigo Carballo, Methodology for positioning a group of green artificial reef based on a database management system, applied in the estuary of Ares-Betanzos (Nw Iberian Peninsula), Journal of Cleaner Production, Volume 233, 2019, Pages 1047-1060, ISSN 0959-6526, https://doi.org/10.1016/j.jclepro.2019.06.092.
0959-6526
http://hdl.handle.net/10347/32273
10.1016/j.jclepro.2019.06.092
Green artificial reef
Database management system
Coastal dynamics
Methodology for positioning a group of green artificial reef based on a database management system, applied in the estuary of Ares-Betanzos (NW Iberian Peninsula)
oai:minerva.usc.es:10347/242872021-01-23T03:01:02Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Mirás Avalos, José Manuel
author
Fandiño Beiro, María
author
Trigo Córdoba, Emiliano
author
Martínez Pérez, Emma María
author
Pereira, José Manuel Moutinho
author
Correia, Carlos M.
author
Dinis, Lia Tânia J.
author
Rey Sanjurjo, Benjamín
author
Malheiro, Aureliano C.
author
Cancela Barrio, Javier José
author
2017
Irrigation has been considered a controversial practice in European traditional viticulture due to potential alterations in the balance between vegetative growth and yield. In this regard, the influence of surface (DI) and subsurface (SDI) drip irrigation on physiological performance of the ‘Godello’ grapevine (Vitis vinifera L.) cultivar was compared with a non-irrigated control (R) over three consecutive growing seasons (2012- 2014) in NW Spain. Irrigation improved vine water status; R plants reached a minimum of midday leaf water potential of –1.5 MPa, whereas DI and SDI plants reached –1.3 MPa. Stomatal conductance was unaffected by irrigation as well as chlorophyll a fluorescence. However, photosynthetic pigments were present at higher concentrations in leaves from irrigated plants than in those from R plants in 2013. In addition, R plants showed higher values for the indicators of oxidative damage. No significant yield improvements were observed for irrigated plants, although the trend was to obtain slightly higher yields under irrigation in years with low rainfall amounts. This may not encourage growers to establish irrigation systems on their vineyards. However, these results may be important with the objectives of stabilizing yield from year to year
A rega tem sido considerada uma prática controversa na viticultura tradicional Europeia devido a potenciais alterações no equilíbrio entre crescimento vegetativo e rendimento. A este respeito, a influência da irrigação por gotejamento superficial (DI) e subsuperficial (SDI) sobre o desempenho fisiológico da variedade ‘Godello’ (Vitis vinifera L.) foi comparada com uma testemunha em condições de sequeiro (R) ao longo de três anos consecutivos (2012-2014) no noroeste de Espanha. A rega melhorou o estado hídrico da videira; as plantas do tratamento R atingiram potenciais hídricos foliares ao meio-dia de –1.5 MPa, comparativamente a um valor de –1.3 MPa para as plantas dos tratamentos DI e SDI. A conductância estomática e a fluorescência da clorofila a não foram afectadas pela rega. No entanto, os pigmentos fotossintéticos apresentaram maiores concentrações em folhas de plantas regadas quando se comparam com as plantas do tratamento R em 2013. Além disso, as plantas do tratamento R apresentaram valores superiores para os indicadores de danos oxidativos. Não foi detectado nenhum incremento do rendimento nas plantas regadas, embora se tenha observado uma tendência para obtenção de rendimentos ligeiramente mais elevados sob rega em anos com baixa pluviosidade. Tal poderá não encorajar aos viticultores a implementar sistemas de rega nas suas vinhas. No entanto, estes resultados podem ser importantes para a estabilização do rendimento de ano para ano
Ciência Téc. Vitiv. 32(1) 42–52. 2017
0254-0223
http://hdl.handle.net/10347/24287
10.1051/ctv/20173201042
Chlorophyll fluorescence
Leaf metabolites
Stomatal conductance
Vitis vinifera
Yield
Fluorescência da clorofila
Metabolitos foliares
Condutância estomática
Vitis vinifera
Rendimento
Effects of surface and subsurface drip irrigation on physiology and yield of ‘Godello’ grapevines grown in Galicia, NW Spain
oai:minerva.usc.es:10347/160362020-04-05T15:26:34Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Martínez Pérez, Emma María
author
Rey Sanjurjo, Benjamín
author
Fandiño Beiro, María
author
Cancela Barrio, Javier José
author
2016
The objective of the present study is to apply different systems of fertigation (rainfed, R; surface drip irrigation, DI, and subsurface drip irrigation, SDI) in Vitis vinifera (L.) cv. ‘Albariño’ to evaluate the cumulative effect of water stress (water stress integral) on yield parameters and to establish the relationship between indices and production. The study was conducted over four years (2010-2013) in a commercial vineyard (Galicia, NW Spain). The volumetric soil water content (θ) (with TDR) and predawn (ψp), midday (ψm) and stem (ψstem) leaf-water potential were determined with a water activity meter during the growing stages (flowering-harvest) from 2010-2013. The number of clusters, their weight and yield/vine were determined at harvest. Must composition was studied to evaluate nutrition treatments. Ψp is presented as the best indicator of the water status of the plant, and the sole use of θ is not recommended as a reference. The soil-plant water status variables were strongly correlated, especially between foliar variables (0.91<R2<0.98), with θ presenting the lowest reliability (0.28<R2<0.81). SDI was the treatment with the highest hydric comfort and greater yield/vine (6.1 kg) and weight per cluster (95.0 g), but lower elements concentration in must. The water stress integral showed that the veraison and harvest stages were very sensitive to water stress in vines. Linear relationships were established between Sψp and W (R2=0.65) and Y (R2=0.56) at veraison. The water stress integral is presented as a useful working tool for vine growers because it allows the prediction of future yield at early phenological states
Martínez, E. M.; Rey, B. J.; Fandiño, M.; Cancela, J. J. (2016). Impact of water stress and nutrition on Vitis vinifera cv. ‘Albariño’: Soil-plant water relationships, cumulative effects and productivity. Spanish Journal of Agricultural Research, Volume 14, Issue 1, e1202. http://dx.doi.org/10.5424/sjar/2016141-7534
1695-971X
http://hdl.handle.net/10347/16036
10.5424/sjar/2016141-7534
2171-9292
Fertigation
Leaf-water potential
Phenological stage
Soil water content
Water activity meter
Water stress integral
Impact of water stress and nutrition on Vitis vinifera cv. ‘Albariño’: Soil-plant water relationships, cumulative effects and productivity
oai:minerva.usc.es:10347/288642023-06-12T12:20:23Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Arza García, Marcos
author
Núñez Temes, Carlos
author
Lorenzana Fernández, Jose Antonio
author
Ortiz Sanz, Juan Pedro
author
Castro Ponte, Alberte
author
Portela Barral, Maria
author
Gil Docampo, María de la Luz
author
Bastos Costas, Guillermo
author
2022
Due to their cost, high-end commercial 3D-DIC (digital image correlation) systems are still inaccessible for many laboratories or small factories interested in lab testing materials. These professional systems can provide reliable and rapid full-field measurements that are essential in some laboratory tests with high-strain rate events or high dynamic loading. However, in many stress-controlled experiments, such as the Brazilian tensile strength (BTS) test of compacted soils, samples are usually large and fail within a timeframe of several minutes. In those cases, alternative low-cost methods could be successfully used instead of commercial systems. This paper proposes a methodology to apply 2D-DIC techniques using consumer-grade cameras and the open-source image processing software DICe (Sandia National Lab) for monitoring the standardized BTS test. Unlike most previous studies that theoretically estimate systematic errors or use local measures from strain gauges for accuracy assessment, we propose a contrast methodology with independent full-field measures. The displacement fields obtained with the low-cost system are benchmarked with the professional stereo-DIC system Aramis-3D (GOM GmbH) in four BTS experiments using compacted soil specimens. Both approaches proved to be valid tools for obtaining full-field measurements and showing the sequence of crack initiation, propagation and termination in the BTS, constituting reliable alternatives to traditional strain gauges. Mean deviations obtained between the low-cost 2D-DIC approach and Aramis-3D in measuring in-plane components were 0.08 mm in the perpendicular direction of loading (ΔX) and 0.06 mm in the loading direction (ΔY). The proposed low-cost approach implies considerable savings compared to commercial systems
Archives of Civil and Mechanical Engineering 22, 4 (2022). https://doi.org/10.1007/s43452-021-00325-0
http://hdl.handle.net/10347/28864
10.1007/s43452-021-00325-0
1644-9665
DIC
Brazilian tensile strength
Stereo vision
GOM
Camera calibration
Full-feld measurements
Evaluation of a low-cost approach to 2-D digital image correlation vs. a commercial stereo-DIC system in Brazilian testing of soil specimens
oai:minerva.usc.es:10347/160962023-07-10T06:12:50Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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Guerra Hernández, Juan
author
Tomé, Margarida
author
González Ferreiro, Eduardo Manuel
author
2016
Este estudio presenta avances en la metodología de inventario forestal a nivel de masa (area-based approach, ABA) con datos LiDAR aerotransportado de baja densidad y destaca la utilidad de los datos LiDAR disponibles para España a escala nacional para realizar cartografía de las principales variables dasométricas en un bosque Mediterráneo de pino piñonero, caracterizado por una compleja orografía. Para ello, se ajustaron modelos lineales de regresión en cada tipo de bosque, a partir de los datos LiDAR de baja densidad (0,5 primeros retornos m–2), proporcionados por el PNOA (Plan Nacional de Ortofotografía Aérea) y los datos obtenidos en campo. Además, se investigó la influencia de los umbrales de altura usados en la extracción de los estadísticos de la nube de puntos LiDAR (MHT: Minimun Height ThresholdyBHT: Break Height Threshold). Los mejores modelos de regresión explicaron un 61-85%, 67-98%, 74-98% de la variabilidad en altura de masa, área basimétrica y volumen, respectivamente. El error de estimación en las variables de masa fue mayor en bosques cerrados mixtos y puros de caducifolias que en los bosques más homogéneos de coníferas. Los resultados demostraron que los umbrales de altura no fueron especialmente críticos en la estimación de las variables de masa en bosques de coníferas, pero hubo diferencias sustanciales en el caso de volumen, cuando aumentaron los umbrales de altura (HBTy MHT) en las masas de estructura más compleja (bosque mixto y puro de caducifolias). Un análisis métrica a métrica reveló la existencia de diferencias significativas en la mayor parte de las variables explicativas extraídas a partir de diferentes umbrales de altura (HBTy MHT). Los mejores modelos de predicción se aplicaron a los rodales de referencia y se elaboró una cartografía espacialmente explícita que representa las principales variables de masa, facilitando así la toma de decisiones para la gestión forestal sostenible en los ecosistemas de bosque mediterráneo
This study reports progress in forest inventory methods involving the use of low density airborne LiDAR data and an area-based approach (ABA). It also emphasizes the usefulness of the Spanish countrywide LiDAR dataset for mapping forest stand attributes in Mediterranean stone pine forest characterized by complex orography. Lowdensity airborne LiDAR data (0.5 first returns m–2) was used to develop individual regression models for a set of forest stand variables in different types of forest. LiDAR data is now freely available for most of the Spanish territory and is provided by the Spanish National Aerial Photography Program (Plan Nacional de Ortofotografía Aérea, PNOA). The influence of height thresholds (MHT: Minimun Height Threshold and BHT: Break Height Threshold) used in extracting LiDAR metrics was also investigated. The best regression models explained 61-85%, 67-98% and 74-98% of the variability in ground-truth stand height, basal area and volume, respectively. The magnitude of error for predicting structural vegetation parameters was higher in closed deciduous and mixed forest than in the more homogeneous coniferous stands. Analysis of height thresholds (HT) revealed that these parameters were not particularly important for estimating several forest attributes in the coniferous forest; nevertheless, substantial differences in volume modelling were observed when the height thresholds (MHT and BHT) were increased in complex structural vegetation (mixed and deciduous forest). A metric-by-metric analysis revealed that there were significant differences in most of the explanatory variables computed from different height thresholds (HBT and MHT).The best models were applied to the reference stands to yield spatially explicit predictions about the forest resources. Reliable mapping of biometric variables was implemented to facilitate effective and sustainable management strategies and practices in Mediterranean Forest ecosystem
Guerra-Hernández, J., Tomé, M., & González-Ferreiro, E. (2016). Using low density LiDAR data to map Mediterranean forest characteristics by means of an area-based approach and height threshold analysis. Revista de Teledetección, 0(46), 103-117. doi:https://doi.org/10.4995/raet.2016.3980
1133-0953
http://hdl.handle.net/10347/16096
10.4995/raet.2016.3980
1988-8740
Láser escáner aerotransportado
Inventario forestal
Cartografía atributos forestales
Teledetección
Modelización forestal
Airborne laser scanning data
Forest inventory
Forest attribute mapping
Remote sensing
Forest modelling
Cartografía de variables dasométricas en bosques Mediterráneos mediante análisis de los umbrales de altura e inventario a nivel de masa con datos LiDAR de baja resolución
oai:minerva.usc.es:10347/166732023-07-10T06:12:20Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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Moreno Fernández, Daniel
author
Álvarez González, Juan Gabriel
author
Rodríguez Soalleiro, Roque
author
Pasalodos Tato, María
author
Cañellas, Isabel
author
Montes, Fernando
author
Díaz-Varela, Emilio
author
Sánchez-González, Mariola
author
Crecente-Campo, Felipe
author
Álvarez Álvarez, Pedro
author
Barrio Anta, Marcos
author
Pérez Cruzado, César
author
2017-06-28
Site productivity of forests is often evaluated thorough the site quality. Different indices can be used to measure site quality but the site index (relationship between dominant height and age) is the most employed. However, site index can only be applied in even-aged forests whereas the site form (height-diameter relationship) has been proved to be a good measure of site quality in uneven-aged stands and multispecies forests. In this work, we aim to develop national-scale site quality maps for five dominant species of Spanish forests (Fagus sylvatica, Pinus pinaster atlantica, Quercus pyrenaica, Pinus nigra, Pinus sylvestris) with landscape planning purposes. First, we develop site form non-linear models using the Spanish National Forest Inventory. Then, we fit spatial additive models entering topographic and climatic variables in order to predict the site quality over the whole country. The accuracy of the models ranged from 38.2% to 47.9%. On the other hand, our results fall well with the autoecology of the species studied. Thus, we confirm the suitability of this approach to estimate the site quality in forest with different structures, such as even or uneven stands. Finally, we suggest that this method can be used in other countries to expand the current maps to the whole Europe
http://hdl.handle.net/10347/16673
European Forest Types
Forest harmonization
Sustainable forest management
International forest policy
Assessing site quality using the National Forest Inventory
oai:minerva.usc.es:10347/220472020-05-06T02:01:36Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Riesco Muñoz, Guillermo
author
Remacha Gete, Andrés
author
Pedras Saavedra, Francisco
author
2011
The European strength class system (EN 338:2009) is based on a testing standard (EN 408:2004) that is not easy
to use with hardwoods, although some of this type of timber, such as European oak (Quercus robur L.), is highly
appreciated for construction purposes. This study proposes specifications for sampling design, visual grading and
mechanical testing of oak wood. With this aim, 27 adult oaks were felled and sawn into pieces. A sample of quartersawn planks was selected, then air-dried and planed to 50 × 100 × 2,000 mm. The beams were visually graded in
accordance with ten standards, and were mechanically tested, at an average wood moisture content of 21%. The Spanish
visual grading standard UNE 56544:2007 was the most effective for categorizing the pieces. According to this standard,
39% of the sampled beams were suitable for structural use. The mean value of modulus of elasticity (11,702 N mm–2)
and characteristic density (714 kg m–3) enable preliminary designation of the wood in visual grade ME-2, to European
strength class D40. However, the bending strength was too low for inclusion of the timber in the European strength
classes. Criteria are proposed for elaborating visual grading rules for oak wood and for structural beam testing in order
to allocate oak visual strength grades into strength classes
El sistema europeo de clases resistentes (EN 338:2009) se basa en una norma de ensayo (EN 408:2004) que es difícil de aplicar en frondosas, aunque algunas de dichas maderas, como el roble (Quercus robur L.), sean muy valoradas en aplicaciones constructivas. En este trabajo se proponen especificaciones para el diseño de muestreo, clasificación visual y ensayo mecánico de la madera de roble. Para el estudio se apearon y aserraron 27 ejemplares adultos
de roble. Se seleccionó una muestra de piezas aserradas claramente radiales, que se secaron al aire y se cepillaron hasta unas dimensiones de 50 × 100 × 2.000 mm. Las viguetas obtenidas se clasificaron visualmente según diez normas
de clasificación y fueron sometidas a ensayo mecánico con un contenido de humedad medio del 21%. La norma española UNE 56544:2007 fue la más eficaz en la clasificación visual de las piezas. Según dicha norma, el 39 % de las
viguetas muestreadas eran aptas para su empleo en estructuras. El modulo elástico medio (11.702 N mm–2) y la densidad característica (714 kg m–3) permitirían una asignación preliminar de la madera de la clase visual ME-2 a la clase resistente europea D40. No obstante, la resistencia a flexión era demasiado baja como para la inclusión de la clase
visual en el sistema europeo de clases resistentes. Se proponen criterios a considerar en la elaboración de una futura
norma de clasificación visual para madera de roble y en el ensayo mecánico de piezas de tamaño estructural, para
asignar clases visuales de roble a clases resistentes
G. Riesco-Muñoz et al. Implications in the design of a method for visual grading and mechanical testing of hardwood structural timber for assignation within the European strength classes. Forest Systems (2011) 20(2), 235-244
1131-7965
http://hdl.handle.net/10347/22047
10.5424/fs/2011202-9771
2171-9845
Quercus robur L.
Visual grading
Sampling design
Testing procedure
Mechanical properties
Clasificación visual
Diseño de muestreo
Método de ensayo
Propiedades mecánicas
Implications in the design of a method for visual grading and mechanical testing of hardwood structural timber for assignation within the European strength classes
oai:minerva.usc.es:10347/216782020-04-24T02:00:33Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Pineda López, María del Rosario
author
Sánchez Velásquez, Lázaro Rafael
author
Vázquez Domínguez, Guillermo
author
Rojo Alboreca, Alberto
author
2013
Aim of study.) Were analyzed patterns and dynamics of forest cover change and land use for the period 1995-2005, and estimated carbon content in biomass in a forest of fir (Abies religiosa).
Area of study. Ejido El Conejo in the Cofre de Perote National Park, Veracruz, Mexico.
Material and Methods. Spatial data (maps, orthophotographs) were used: (UTM); GRS 80 spheroid; zone 14, datum ITRF92; units: metres. Maps for 1995 and 2005 were constructed and compared. Carbon content in the aboveground biomass of fir (Abies religiosa) was estimated using an equation specific to species.
Main results. After one decade, the forested area had increased slightly (0.25%). The main type of land cover change was from shrubland to forest (probability of change 0.41); the change from forestland to shrubland with trees was 0.05%, and from forest to agriculture was 0.02%. Data from 2008 confirmed that the A. religiosa forest located in the ejido is distributed in largely unconnected fragments, of which some have a high density of young trees. Estimated carbon content in the aboveground biomass (163.51 Mg ha-1) was higher than that estimated for other forests of the same species in Mexico.
Research highlights. It is recommended that ecological corridors be established throughout the reforested area, in order to connect these fragments (and increase carbon sequestration) and favour faunal and floral conservation. Finally, recognition should be given to the high vulnerability of A. religiosa forests to climate change, given their high degree of fragmentation and critical altitudinal limit
Pineda-Lopez, M. R., Sanchez-Velasquez, L. R., Vazquez-Dominguez, G., Rojo-Alboreca, A. (2013). The effects of land use change on carbon content in the aerial biomass of an Abies religiosa (Kunth Schltdl. et Cham.) forest in central Veracruz, Mexico. "Forest Systems" Vol. 22, n.1, p. 82-93
2171-5068
http://hdl.handle.net/10347/21678
10.5424/fs/2013221-02756
2171-9845
Aboveground biomass
Carbon storage
Ecological corridors
Fir forest
The effects of land use change on carbon content in the aerial biomass of an Abies religiosa (Kunth Schltdl. et Cham.) forest in central Veracruz, Mexico
oai:minerva.usc.es:10347/217502023-07-10T06:16:42Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_9747col_10347_15615
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Bravo Oviedo, Felipe
author
Álvarez González, Juan Gabriel
author
Río Gaztelurrutia, Miren del
author
Barrio Anta, Marcos
author
Bonet, José Antonio
author
Bravo Oviedo, Andrés
author
Calama Sainz, Rafael
author
Castedo Dorado, Fernando
author
Crecente Campo, Felipe
author
Condés Ruiz, Sonia
author
Diéguez Aranda, Ulises
author
González Martínez, Santiago César
author
Lizarralde Torre, Iñigo
author
Nanos, Nikolaos
author
Madrigal Collazo, Alberto
author
Martínez Millán, Francisco Javier
author
Montero González, Gregorio
author
Ordóñez Alonso, Ángel Cristóbal
author
Palahí, Marc
author
Piqué Nicolau, Míriam
author
Rodríguez Puerta, Francisco
author
Rodríguez Soalleiro, Roque
author
Rojo Alboreca, Alberto
author
Ruiz-Peinado Gertrudix, Ricardo
author
Sánchez González, Mariola
author
Trasobares Rodríguez, Antoni
author
Vázquez Piqué, Javier
author
2011
In this paper we present a review of forest models developed in Spain in recent years for both timber and non timber production and forest dynamics (regeneration, mortality,..). Models developed are whole stand, size (diameter) class and individual-tree. The models developed to date have been developed using data from permanent plots, experimental sites and the National Forest Inventory. In this paper we show the different sub-models developed so far and the friendly use software. Main perspectives of forest modelling in Spain are presented.
En el presente trabajo se presenta una revisión sobre los modelos forestales desarrollados en España durante los últimos años, tanto para la producción maderable como no maderable y, para la dinámica de los bosques (regeneración, mortalidad). Se presentan modelos tanto de rodal completo como de clases diamétricas y de árbol individual. Los modelos desarrollados hasta la fecha se han desarrollado a partir de datos procedentes de parcelas permanentes, ensayos y el Inventario Forestal Nacional. En el trabajo se muestran los diferentes submodelos desarrollados hasta la fecha,así como las plataformas informáticas que permiten utilizar dichos modelos. Se incluyen las principales perspectivas
de desarrollo de la modelización forestal en España.
Bravo, F., Alvarez-Gonzalez, J., del Rio, M., Barrio, M., Bonet, J., Bravo-Oviedo, A., Calama, R., Castedo-Dorado, F., Crecente-Campo, F., Condes, S., Dieguez-Aranda, U., Gonzalez-Martinez, S., Lizarralde, I., Nanos, N., Madrigal, A., Martinez-Millan, F., Montero, G., Ordoñez, C., Palahi, M., Pique, M., Rodriguez, F., Rodriguez-Soalleiro, R., Rojo, A., Ruiz-Peinado, R., Sanchez-Gonzalez, M., Trasobares, A., & Vazquez-Pique, J. (2011). Growth and yield models in Spain: Historical overview, Contemporary Examples and perspectives. Forest Systems, 20(2), 315-328. doi:http://dx.doi.org/10.5424/fs/2011202-11512
1131-7965
http://hdl.handle.net/10347/21750
10.5424/fs/2011202-11512
2171-9845
Timber production
Non-wood production
Recruitment
Modeling
Forest
Producción maderable
Productos no maderables
Regeneración
Modelización
Forestal
Growth and yield models in Spain: Historical overview, Contemporary Examples and perspectives
oai:minerva.usc.es:10347/75362020-01-31T12:05:06Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_760com_10347_250col_10347_10081col_10347_767
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Álvarez González, Juan Gabriel
author
1996
ÁLVAREZ GONZÁLEZ, J. G.: «Caracterización de las proteínas de semilla de Pinus pinea L.», Nova Acta Científica Compostelana (Bioloxía), vol. 7 (1996): pp. 103-110. ISSN 1130-9717
1130-9717
http://hdl.handle.net/10347/7536
Pinus pinea L.
Semillas
Proteínas de reserva
Caracterización de las proteínas de semilla de Pinus pinea L.
oai:minerva.usc.es:10347/196412021-05-21T07:29:29Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_8426com_10347_250col_10347_10081col_10347_18924
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Corbelle Rico, Eduardo José
author
Crecente Maseda, Rafael
author
2008
O abandono de terras e a conseguinte diminución da superficie utilizada pola agricultura
constitúe un problema importante nun gran número de rexións da Unión Europea entre as
que se atopa Galicia. A posta en marcha do Banco de Terras de Galicia no ano 2007 está dirixida
a corrixir, dentro do posible, esta situación que enlaza cos elementos centrais da problemática
do campo galego contemporáneo: a incidencia catastrófica dos incendios forestais, a redución
e progresivo envellecemento da poboación rural e un ineficaz uso do territorio que dificulta
a competitividade do sector agrario. Con todo, o propio concepto de abandono pode dar lugar a
diferentes interpretacións, co que semella necesaria unha clarificación do termo. Neste contexto
preséntase unha discusión sobre os conceptos teóricos máis importantes en relación co abandono
de terras e achégase unha revisión da literatura científica existente sobre o tema. A maiores,
o traballo pon a énfase no carácter multidimensional do problema e a necesidade de complementar
os estudos de carácter exclusivamente económico con outros centrados na compoñente
territorial do proceso
El abandono de tierras y la consiguiente disminución de la superficie utilizada por la agricultura constituye un problema importante en un gran número de regiones de la Unión Europea entre las que se encuentra Galicia. La puesta en marcha del Banco de Tierras de Galicia en el año 2007 está dirigida a corregir, dentro de lo posible, esta situación que enlaza con los elementos centrales de la problemática del campo gallego contemporáneo: la incidencia catastrófica de los incendios forestales, la reducción y progresivo envejecimiento de la población rural y un ineficaz uso del territorio que dificulta la competitividad del sector agrario. No obstante, el propio concepto de abandono puede dar lugar a diferentes interpretaciones, por lo que parece necesaria una clarificación del término. En este contexto se presenta una discusión sobre los conceptos teóricos más importantes en relación con el abandono de tierras y se facilita una revisión de la literatura científica existente sobre el tema. A mayores, el trabajo enfatiza el carácter multidimensional del problema y la necesidad de complementar los estudios de carácter exclusivamente económico con otros centrados en la componente territorial del proceso
Land abandonment, and the resulting decrease in Utilised Agricultural Area is a matter
of great concern in regions within the European Union, among which Galicia is included. Precisely,
the new Land Bank of Galicia has been put to work in 2007 to address this situation, related
to many important issues in rural areas in Galicia: the catastrophic dimensions of forest fires,
the decline and ageing of rural population, and an inefficient use of land which limits the competitiveness
of the agricultural sector. It is worth noting, though, that the term abandonment itself
needs some clarification. With this frame in mind, a theoretic discussion and a literature review
on the subject are presented. Moreover, the paper emphasizes the multidimensional character of
the problem and the need of complementing the economic studies with others, more focused on
the territorial perspective
Revista Galega de Economía, vol. 17, núm. 2 (2008), pp. 47-62 ISSN 1132-2799
1132-2799
http://hdl.handle.net/10347/19641
2255-5951
Abandono de terras
Banco de terras
SAU
Terra marxinal
Incendios
Abandono de tierras
Banco de tierras
Tierra marginal
Land abandonment
Land bank
UAA
Marginal land
Forest fires
O abandono de terras: concepto teórico e consecuencias
oai:minerva.usc.es:10347/218802020-05-20T18:42:47Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Rey Prieto, Adrián
author
Riesco Muñoz, Guillermo
author
2012
La madera de Pinus sylvestris tiene interés comercial aunque su valor se reduce considerablemente cuando presenta hongos de azulado. En el presente estudio se apearon siete pinos procedentes de plantaciones españolas, y de los fustes se muestrearon 14 rodajas a diferentes alturas. Cuando éstas estaban parcialmente azuladas se labraron para obtener probetas pequeñas sin defectos anatómicos, sobre las que se determinó la densidad y además la estabilidad dimensional en volumen y en las tres dimensiones principales de la madera. En cada rodaja se compararon las propiedades físicas de las probetas completamente azuladas y las no azuladas, mediante el análisis de la varianza con un factor.
El método permitió analizar la influencia específica del azulado eliminando otras fuentes de variación: factor árbol, altura en el fuste, anchura de anillos, presencia de albura y edad cambial. Solo en algunas rodajas la madera azulada de pino silvestre resultó signifi-cativamente diferente en densidad y contracción axial (madera azulada un 1% más densa y con la contracción axial un 13% mayor)
Pinus sylvestris timber is commercially important, but its value is considerably decreased by the effects of blue stain fungi. Seven pine trees from Spanish plantations were felled for the study, and 14 discs were sampled from different heights in their stems. When the discs showed partial discolouration due to fungal infection, they were cut to produce small defect-free specimens for determining density and dimensional stability (in volume and in the three main dimensions of wood). The physical properties of fully stained and stain free specimens were compared, in each disc, by one-factor analysis of variance. This method enabled analysis of the specific influence of the blue stain fungi while avoiding other sources of variation: tree factor, height in the stem, ring width, presence of sapwood and cambial age. However, the only signicant differences between discoloured and unstained wood were in the density and axial shrinkage, in some discs (the density of the blue-stained wood was 1% higher and the axial shrinkage 13% higher than in the unstained wood)
Adrián Rey-Prieto, Adrián, Riesco-Muñoz, Guillermo. (2012). Influencia del azulado "mancha azul" en la densidad y estabilidad dimensional de la madera de pinus silvestrys. "Maderas. Ciencia y tecnología" vol. 14, n.1, p. 115-125
0717-3644
http://hdl.handle.net/10347/21880
10.4067/S0718-221X2012000100010
0718-221X
Pino silvestre
Pinus sylvestris
Densidad
Contracción
Hongos de azulado.
Scots pine
Pinus sylvestris
Density
Shrinkage
Blue stain
Influencia del azulado (mancha azul) en la densidad y estabilidad dimensional de la madera de Pinus sylvestris
oai:minerva.usc.es:10347/241812021-01-15T03:00:49Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Díaz Maroto, María Consuelo
author
López Viñas, Manuel
author
Marchante, Lourdes
author
Alañón, María Elena
author
Díaz Maroto, Ignacio Javier
author
Pérez Coello, María Soledad
author
2021
The effects of different storage conditions, light exposure, temperature and different commercially available cork stoppers on the phenolic, volatile and sensorial profile of Verdejo wines were studied. Two natural corks of different visual quality and a microgranulated cork stopper were investigated over one year at two different storage conditions. One simulating light exposure and temperature in retail outlets and the other simulating optimal cellar conditions (darkness and 12 °C). The wines stored under commercial conditions showed greater losses of total and free SO2 and higher levels of brown-yellowish tones, related to the oxidation of flavan-3-ols. Although these wines underwent a decrease in the total content of stilbenes, a significant increase in trans-piceid was observed. In addition, these wines suffered important changes in their volatile and sensory profile. Volatile compounds with fruity and floral aromas decreased significantly, while volatile compounds related to aged-type characters, as linalool oxides, vitispirane, TDN or furan derivatives increased. Wines stored in darkness at 12 °C underwent minor changes and their sensory profiles were similar to wine before bottling. The high-quality natural corks and microgranulated corks better preserved the quality of the white wines from a sensory point of view. These results showed that temperature and light exposure conditions (diffuse white LEDs and 24 ± 2 °C) in retail outlets considerably decrease the quality of bottled white wines and, consequently, their shelf life, due to the premature development of aged-type characters
Díaz-Maroto, M.C.; López Viñas, M.; Marchante, L.; Alañón, M.E.; Díaz-Maroto, I.J.; Pérez-Coello, M.S. Evaluation of the Storage Conditions and Type of Cork Stopper on the Quality of Bottled White Wines. Molecules 2021, 26, 232
http://hdl.handle.net/10347/24181
10.3390/molecules26010232
1420-3049
Shelf life
Storage
Cork
Wine
Phenolic compounds
Volatile compounds
Sensorial
Evaluation of the Storage Conditions and Type of Cork Stopper on the Quality of Bottled White Wines
oai:minerva.usc.es:10347/247072023-07-10T06:21:39Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2918com_10347_2891com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_13951col_10347_9747col_10347_15615
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Molina Valero, Juan Alberto
author
Ginzo Villamayor, María José
author
Novo Pérez, Manuel Antonio
author
Álvarez González, Juan Gabriel
author
Pérez Cruzado, César
author
2019
El láser escáner terrestre (TLS) ha surgido como un nuevo dispositivo de tecnología LiDAR con un gran potencial para ser implementado en inventarios forestales (IIFF). En este trabajo se ha desarrollado un algoritmo con el que se obtienen métricas capaces de estimar el área basimétrica a nivel de parcela (G) en base a una única medición del TLS. El estudio se ha realizado en masas maduras de Pinus sylvestris, inventariadas mediante una red de 40 parcelas que cubren casi por completo el área de distribución y rango de calidades de la especie en España. Este algoritmo se compone de cuatro pasos fundamentales: (1) normalización de la nube de puntos obtenida con el TLS, (2) identificación de los árboles, (3) reducción de la densidad de la nube de puntos, y (4) obtención de las métricas relacionadas con el G. Los mejores resultados se han obtenido con el G estimada en parcelas de 7 m de radio, alcanzando un coeficiente de correlación de Pearson de 0.86 significativo al 95 %. Esto ha permitido obtener modelos de regresión lineal simple con valores de R2adjy RECM de 0.75 y 10.66 m2 para toda la colección de parcelas, y 0.82 y 8.57 m2 para las parcelas agregadas por sitio. Aunque estos resultados sugieren que el TLS podría ser útil para la estimación del G en pinares de P. sylvestris, sería necesario contrastarlo en masas que cubran todos los estados de desarrollo para validar su uso en un mayor rango de estados estructurales
Terrestrial Laser Scanner (TLS) has emerged as a new LiDAR device with high potential to be implemented in forest inventories (FI). In this work has been developed an algorithm to obtain metrics related to stand basal area (G). The research has been performed in mature stands of Pinus sylvestris through 40 plots covering almost all the distribution area and range of site qualities for this species in Spain. This algorithm is based on four main steps: (1) normalisation of point clouds obtained with TLS, (2) identification of individuals trees, (3) reduction in density of the point cloud, and (4) obtaining metrics related to G. The G estimated in plots of 7 m of radio shown the best results with a Pearson correlation coefficient value of 0.86. This has enabled to achieve a linear regression model with values of 0.75 and 10.66 m2 for R2adj and RMSE respectively for all the plots. Assessing linear regression model by site, R2adj and RMSE reached higher values of 0.82 y 8.57 m2. Although these results suggest TLS as a good tool to estimate G in mature stands of P. sylvestris, further research covering all the develop stages is necessary to contrast estimated G in stands with different structures
Cuad. Soc. Esp. Cienc. For. 45(3): 97-116 (2019). Doi: https://doi.org/10.31167/csecfv0i45.19887
1575-2410
http://hdl.handle.net/10347/24707
10.31167/csecfv0i45.19887
2386-8368
Inventario forestal
LiDAR
Métricas
Teledetección
Variables dasométricas
Forest inventory
Metrics
Remote sensing
Dasometric variables
Estimación del área basimétrica en masas maduras de Pinus sylvestris en base a una única medición del escáner láser terrestre (TLS)
oai:minerva.usc.es:10347/216772020-04-24T02:01:37Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Merlo, Esther
author
Álvarez González, Juan Gabriel
author
Santaclara, Oscar
author
Riesco Muñoz, Guillermo
author
2014
Aim of study: Modelling the structural quality of Pinus pinaster Ait. wood on the basis of measurements made on standing trees is essential because of the importance of the species in the Galician forestry and timber industries and the good mechanical properties of its wood. In this study, we investigated how timber stiffness is affected by tree and stand properties, climatic and edaphic characteristics and competition.
Area of study: The study was performed in Galicia, north-western Spain.
Material and methods: Ten pure and even-aged P. pinaster stands were selected and tree and stand variables and the stress wave velocity of 410 standing trees were measured. A sub-sample of 73 trees, representing the variability in acoustic velocity, were felled and sawed into structural timber pieces (224) which were subjected to a bending test to
determine the modulus of elasticity (MOE).
Main results: Linear models including wood properties explained more than 97%, 73% and 60% of the observed MOE variability at site, tree and board level, respectively, with acoustic velocity and wood density as the main regressors.
Other linear models, which did not include wood density, explained more than 88%, 69% and 55% of the observed MOE variability at site, tree and board level, respectively, with acoustic velocity as the main regressor. Moreover, a classification tree for estimating the visual grade according to standard UNE 56544:2011 was developed.
Research highlights: The results have demonstrated the usefulness of acoustic velocity for predicting MOE in standing trees. The use of the fitted equations together with existing dynamic growth models will enable preliminary assessment of timber stiffness in relation to different silvicultural alternatives used with this species.
Merlo, Esther, Alvarez Gonzalez, Juan Gabriel, Santaclara, Oscar, Riesco, Guilermo. (2014).Modelling modulus of elasticity of Pinus pinaster Ait. in northwestern Spain with standing tree acoustic measurements, tree, stand and site variables."Forest Systems" Vol. 23, n.1 p. 153-166
2171-5068
http://hdl.handle.net/10347/21677
10.5424/fs/2014231-04706
2171-9845
Stress wave velocity
Modulus of elasticity
Site index
Competition index
Stepwise regression
CART
Modelling modulus of elasticity of Pinus pinaster Ait. in northwestern Spain with standing tree acoustic measurements, tree, stand and site variables
oai:minerva.usc.es:10347/38042022-07-04T12:29:22Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250com_10347_2956col_10347_10081col_10347_3774col_10347_9747
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Cuesta García, Tomás Serafín
author
Neira Seijo, Xan Xosé
author
Álvarez López, Carlos José
author
Cancela Barrio, Javier José
author
2007
El primer paso en la aplicación del Plan nacional
de Regadíos (PNR) debe ser el análisis del uso del agua en
los regadíos tradicionales. Para ello nos interesa definir las
prácticas de riego habituales y evaluar la incidencia social
del regadío en el ámbito rural. En este trabajo se presentan
los resultados obtenidos en el estudio realizado en la zona
regable del Valle de Lemos (Lugo, España). Se ha realizado
una encuesta de campo incluyendo aspectos técnicos y
sociales, así como evaluaciones de riego en parcelas de
ensayo repartidas entre las clases de suelos existentes.
Esta zona se caracteriza por una baja eficiencia en el uso
del agua, unas pérdidas importantes en la red de
distribución, una estructura atomizada de la propiedad y un
escaso aprovechamiento de las infraestructuras existentes.
A pesar de estos inconvenientes, la existencia de una
importante red de distribución y la disponibilidad de agua
hacen de la modernización
1885-5547
http://hdl.handle.net/10347/3804
Gestión del riego
Modernización
Parámetros sociales
Irrigation management
Modernisation
Social parameters
Caracterización del regadío en la zona regable del Valle de Lemos (Lugo, España)
oai:minerva.usc.es:10347/210572023-07-10T06:17:48Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Villar García, José Ramón
author
Vidal López, Pablo
author
Crespo Outes, Jorge
author
Guaita Fernández, Manuel
author
2019
The double-step joint is among the most frequently used layouts, within carpentry joints, for transmitting higher forces that would allow a single notch. They are especially effective in heavy timber structures. Nowadays, computer-aided manufacturing is being used more often, demanding further progress in its understanding. The conventional design of these joints is conducted by using simplifying assumptions, in particular regarding the shear stress distribution. This is overcome by the use of strength reduction coefficient, which is
currently under study. Numerical simulation and experimental tests were carried out with heavy timber crosssections for rafter to tie-beam truss joint. They were manufactured in glue-laminated timber owing to the large cross-sections tested. Experimental load-strain and load-displacement diagrams were compared with numerical results. This allowed observing the great shear stress concentration produced in the failure by shear crack, which
suggests the application of conservative shear strength reduction coefficients.
Análisis del estado tensional de la unión por embarbillado doble en estructuras pesadas de madera.
Entre las uniones carpinteras, el embarbillado doble es una de las más utilizadas para transmitir cargas superiores a las que permitiría una única entalladura, especialmente interesante para estructuras pesadas. Hoy en
día, la fabricación asistida por ordenador ha estimulado su uso, demandando profundizar en su estudio. El
diseño convencional de estas uniones se realiza asumiendo supuestos simplificadores, en particular respecto a la
distribución de las tensiones tangenciales en el cogote. Derivando en el empleo de factores de penalización de la
resistencia, los cuales continúan actualmente en estudio. Se realizaron ensayos con escuadrías propias de cerchas
pesadas en configuración par-tirante, empleándose para ello madera laminada. Los gráficos experimentales
de carga-deformación y carga-desplazamiento se compararon con la modelización numérica de la unión. Esto
permitió apreciar la importante concentración de tensiones tangenciales que se produce en el fallo por rasante,
lo que aconseja la aplicación de factores reductores de resistencia a cortante conservadores.
Villar-García, J. R., Vidal-López, P., Crespo, J., & Guaita, M. (2019). Analysis of the stress state at the double-step joint in heavy timber structures. Materiales de Construcción, 69(335), 196.
0465-2746
http://hdl.handle.net/10347/21057
10.3989/mc.2019.00319
1988-3226
Wood
Method of finite elements
Modelization
Mechanical properties
Deformation
Madera
Análisis de elementos finitos
Modelización
Propiedades mecánicas
Deformación
Analysis of the stress state at the double-step joint in heavy timber structures
oai:minerva.usc.es:10347/301892023-02-23T03:03:02Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Rodríguez Rodriguez, Manuel Ramiro
author
Besteiro Doval, Roberto
author
Ortega Martínez, Juan Antonio
author
Fernández Rodríguez, María Dolores
author
Arango López, Tamara
author
2022
This paper aims to study the evolution of CO2 concentrations and emissions on a conventional farm with weaned piglets between 6.9 and 17.0 kg live weight based on setpoint temperature, outdoor temperature, and ventilation flow. The experimental trial was conducted during one transition cycle. Generally, the ventilation flow increased with the reduction in setpoint temperature throughout the cycle, which caused a reduction in CO2 concentration and an increase in emissions. The mean CO2 concentration was 3.12 g m–3. Emissions of CO2 had a mean value of 2.21 mg s−1 per animal, which is equivalent to 0.195 mg s−1 kg−1. A potential function was used to describe the interaction between 10 min values of ventilation flow and CO2 concentrations, whereas a linear function was used to describe the interaction between 10 min values of ventilation flow and CO2 emissions, with r values of 0.82 and 0.85, respectively. Using such equations allowed for simple and direct quantification of emissions. Furthermore, two prediction models for CO2 emissions were developed using two neural networks (for 10 min and 60 min predictions), which reached r values of 0.63 and 0.56. These results are limited mainly by the size of the training period, as well as by the differences between the behavior of the series in the training stage and the testing stage
Rodriguez, M.R.; Besteiro, R.; Ortega, J.A.; Fernandez, M.D.; Arango, T. Evolution and Neural Network Prediction of CO2 Emissions in Weaned Piglet Farms. Sensors 2022, 22, 2910. https://doi.org/10.3390/s22082910
1424-8220
http://hdl.handle.net/10347/30189
10.3390/s22082910
CO2 concentration
CO2 emission
Neural network
Weaned piglets
Post weaning cycle
Evolution and neural network prediction of CO2 emissions in weaned piglet farms
oai:minerva.usc.es:10347/148292023-07-10T06:16:24Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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Gorgoso Varela, José Javier
author
García Villabrille, Juan Daniel
author
Rojo Alboreca, Alberto
author
Gadow, Klaus von
author
Álvarez González, Juan Gabriel
author
2016
Aim of study: In this study we compare the accuracy of three bivariate distributions: Johnson’s SBB, Weibull-2P and LL-2P functions for characterizing the joint distribution of tree diameters and heights.
Area of study: North-West of Spain.
Material and methods: Diameter and height measurements of 128 plots of pure and even-aged Tasmanian blue gum (Eucalyptus
globulus Labill.) stands located in the North-west of Spain were considered in the present study. The SBB bivariate distribution was obtained from SB marginal distributions using a Normal Copula based on a four-parameter logistic transformation. The Plackett Copula was used to obtain the bivariate models from the Weibull and Logit-logistic univariate marginal distributions. The negative
logarithm of the maximum likelihood function was used to compare the results and the Wilcoxon signed-rank test was used to compare the related samples of these logarithms calculated for each sample plot and each distribution.
Main results: The best results were obtained by using the Plackett copula and the best marginal distribution was the Logit-logistic.
Research highlights: The copulas used in this study have shown a good performance for modeling the joint distribution of tree diameters and heights. They could be easily extended for modelling multivariate distributions involving other tree variables, such as tree volume or biomass
Gorgoso-Varela, J.J., García-Villabrille, J.D., Rojo-Alboreca, A., Gadow, K.v., Álvarez-González, J.G. (2016). Comparing Johnson’s SBB, Weibull and Logit-Logistic bivariate distributions for modeling tree diameters and heights using copulas. Forest Systems, Volume 25, Issue 1, eSC07. http://dx.doi.org/10.5424/fs/2016251-08487
2171-9845
http://hdl.handle.net/10347/14829
10.5424/fs/2016251-08487
Plackett copula
Normal copula
Eucalyptus globulus
Comparing Johnson’s SBB, Weibull and Logit-Logistic bivariate distributions for modeling tree diameters and heights using copulas
oai:minerva.usc.es:10347/216722020-04-24T02:00:26Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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Canga, Elena
author
Diéguez Aranda, Ulises
author
Afif-Khouri, Elías
author
Cámara Obregón, Asunción
author
2013
Aim of the study: The aim of this study was to develop a model for above-ground biomass estimation for Pinus radiata D. Don in Asturias.
Area of study: Asturias (NE of Spain).
Material and methods: Different models were fitted for the different above-ground components and weighted regression was used to correct heteroscedasticity. Finally, all the models were refitted simultaneously by use of Nonlinear Seemingly Unrelated Regressions (NSUR) to ensure the additivity of biomass equations.
Research highlights: A system of four biomass equations (wood, bark, crown and total biomass) was develop, such that the sum of the estimations of the three biomass components is equal to the estimate of total biomass. Total and stem biomass equations explained more than 92% of observed variability, while crown and bark biomass equations explained 77% and 89% respectively.
Canga, E., Diéguez-Aranda, U., Elias, A. K., and Cámara, A. (2013). Above-ground biomass equations for Pinus radiata D. Don in Asturias. Forest Systems, 22(3), 408-415.
2171-5068
http://hdl.handle.net/10347/21672
10.5424/fs/2013223-04143
2171-9845
Radiata pine
Plantations
Biomass
Above-ground biomass equations for Pinus radiata D. Don in Asturias
oai:minerva.usc.es:10347/176152020-10-22T12:34:35Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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Pineda López, María del Rosario
author
Ruelas Inzunza, Ernesto
author
Sánchez-Velásquez, Lázaro R.
author
Espinoza Guzmán, Marco A.
author
Rojo Alboreca, Alberto
author
Vásquez-Morales, Suria G.
author
2017-11-18
To understand the dynamics of land cover at the Parque Nacional Cofre de Perote, the rates of change in land use were compared at two
different scales during the period 1995-2004. At the meso scale, these patterns were studied throughout the entire Parque Nacional Cofre
de Perote, which is one of the 60 priority mountains of Mexico, and an important natural protected area of the country located in the
state of Veracruz. At a micro scale, the work was focused in ejido El Conejo, located within the boundaries of this national park. Federal
government digital orthophotos were used to determine changes in nine categories of land use. In both, the meso- and micro-scale, it was
found that the predominant land cover categories are agriculture and forest. The probabilities of land cover change at both scales are
low and essentially the same for most land use categories, reflecting both small gains in forest cover park-wide as well as the effectiveness
of the ejido in managing natural resources within the park. The authors consider that the findings of the study may be applicable to the
broader situation of national parks in Mexico and, finally, the importance of integrating local stakeholders in the management of natural
protected areas is discussed
Para entender la dinámica de la cobertura del suelo en el Parque Nacional Cofre de Perote, se hizo una comparación de las tasas de cambio de uso a dos escalas durante el periodo 1995-2004. A escala meso, se estudiaron estos patrones en toda la superficie del Parque Nacional Cofre de Perote, que es una de las 60 montañas prioritarias de México y también una importante área natural protegida del país ubicada en el estado de Veracruz. A escala micro el estudio se enfocó en el ejido El Conejo que se encuentra dentro de los límites de este parque nacional. Se utilizaron ortofotos digitales del gobierno federal para determinar el cambio en nueve categorías de uso del suelo. En ambas, meso y microescalas, se encontró que las categorías predominantes de cobertura son la agricultura y el bosque. Las probabilidades de cambio de cobertura del suelo en ambas escalas son bajas y tienen valores esencialmente iguales para la mayoría de las categorías de uso, reflejando tanto pequeñas ganancias en cobertura forestal en todo el parque como la efectividad del ejido en el manejo de recursos naturales dentro del parque. Se considera que los hallazgos de este estudio pueden ser aplicables a la situación prevaleciente en los restantes parques nacionales de México; al final se discute la importancia de integrar a los actores locales en el manejo de áreas naturales protegidas
Pineda-López, M., Ruelas Inzunza, E., Sánchez-Velásquez, L., Espinoza Guzmán, M., Rojo Alboreca, A., & Vásquez-Morales, S. (2017). Dinámica de uso y cobertura del suelo en un parque nacional mexicano. Madera y Bosques, 23(3), 87-99. doi:https://doi.org/10.21829/myb.2017.2331492
1405-0471
http://hdl.handle.net/10347/17615
10.21829/myb.2017.2331492
Cartography
Parque Nacional Cofre de Perote
Digital orthophotos
Ejido El Conejo
Land use
Transition matrix
Cartografía
Matriz de transición
Ortofotos digitales
Uso del suelo
Dynamics of land use and land cover in a Mexican national park
oai:minerva.usc.es:10347/247062023-07-10T06:21:39Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2956com_10347_15613com_10347_15468col_10347_10081col_10347_9747col_10347_15615
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Pérez Cruzado, César
author
Kleinn, Christoph
author
Magdon, Paul
author
Álvarez González, Juan Gabriel
author
Magnussen, Steen
author
Fehrmann, Lutz
author
Nölke, Nils
author
2021
Forest biomass is currently among the most important and most researched target variables in forest monitoring. The common approach of observing individual tree biomass in forest inventory is to assign the total tree biomass to the dimensionless point of the tree position. However, the tree biomass, in particular in the crown, is horizontally distributed above the crown projection area. This horizontal distribution of individual tree biomass (HBD) has not attracted much attention—but if quantified, it can improve biomass estimation and help to better represent the spatial distribution of forest fuel. In this study, we derive a first empirical model of the branch HBD for individual trees of European beech (Fagus sylvatica L.). We destructively measured 23 beech trees to derive an empirical model for the branch HBD. We then applied Terrestrial Laser Scanning (TLS) to a subset of 17 trees to test a simple point cloud metric predicting the branch HBD. We observed similarities between a branch HBD and commonly applied taper functions, which inspired our HBD model formulations. The models performed well in representing the HBD both for the measured biomass, and the TLS-based metric. Our models may be used as first approximations to the HBD of individual trees—while our methodological approach may extend to trees of different sizes and species
Remote Sens. 2021, 13(5), 1041; https://doi.org/10.3390/rs13051041
http://hdl.handle.net/10347/24706
10.3390/rs13051041
2072-4292
Terrestrial laser scanning (TLS)
Sampling
Forest inventory
Forest monitoring
Biomass models
The Horizontal Distribution of Branch Biomass in European Beech: A Model Based on Measurements and TLS Based Proxies
oai:minerva.usc.es:10347/38112022-11-14T13:56:41Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250col_10347_10081col_10347_3775
00925njm 22002777a 4500
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Corbelle Rico, Eduardo José
author
Crecente Maseda, Rafael
author
2008
O abandono da terra agrícola é un tema de plena
actualidade en Galicia: existen traballos científicos que
confirman a súa existencia, textos legais que falan da
“continua perda de superficie agraria útil”, e evidencias
visuais para calquera observador atento. Non obstante, o
problema atópase pendente de ser cuantificado e ubicado
territorialmente, en grande medida porque a insuficiente
desagregación espacial dos datos estatísticos dispoñibles
sobre coberturas ou usos do solo non permite capturar a
súa grande complexidade. Neste traballo achégase unha
aproximación cartográfica ó problema tomando como base
a escala municipal, dentro dunha das comarcas máis
dinámicas do sector agrario galego, e cunha perspectiva
temporal a medio prazo. Os resultados confirman a
diminución da superficie agrícola da comarca, pero destaca
o feito de que esa diminución se concentrou exclusivamente
nunha parte dos concellos que a integran, mentres que o
resto se mantiveron nos niveis de 1956 ou incluso os
incrementaron. Deste resultado conclúese a necesidade de
territorializar as políticas concebidas para combatir o
abandono e as súas consecuencias negativas, de modo
que se actúe principalmente nas áreas máis afectadas.
1885-5547
http://hdl.handle.net/10347/3811
SAU
Uso do solo
Abandono de terras
Sistemas de información xeográfica
Fotografía aérea
UAA
Land use and abandonment
Geographic information systems
Aerial photography
Estudio da evolución da superficie agrícola na comarca da Terra Chá a partir de fotografía aérea histórica e mapas de usos, 1956-2004
oai:minerva.usc.es:10347/148352023-07-10T06:12:13Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
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Rojo Alboreca, Alberto
author
García Villabrille, Juan Daniel
author
Pérez Rodríguez, Fernando
author
2015
Aim of study: To present the software utilities and explain how to use EucaTool®, a free cloud computing application developed to estimate the growth and production of seedling and clonal blue gum (Eucalyptus globulus Labill.) plantations in Galicia (NW
Spain). Area of study: Galicia (NW Spain).
Material and methods: EucaTool® implements a dynamic growth and production model that is valid for clonal and non-clonal blue gum plantations in the region. The model integrates transition functions for dominant height (site index curves), number of stems per hectare (mortality function) and basal area, as well as output functions for tree and stand volume, biomass and carbon content. Main results: EucaTool® can be freely accessed from any device with an Internet connection, from http://app.eucatool.com. In addition, useful information about the application is published on a related website: http://www.eucatool.com.
Research highlights: The application has been designed to enable forest stakeholders to estimate volume, biomass and carbon content of forest plantations from individual trees, diameter classes or stand data, as well as to estimate growth and future production (indicating the optimal rotation age for maximum income) by measurement of only four stand variables: age, number of tres per hectare, dominant height and basal area
Rojo-Alboreca, A., García-Villabrille, J.D., Pérez-Rodríguez, F. (2015). EucaTool®, a cloud computing application for estimating the growth and production of Eucalyptus globulus Labill. plantations in Galicia (NW Spain). Forest Systems, Volume 24, Issue 3, eRC06, 4 pages. http://dx.doi.org/10.5424/fs/2015243-07865
2171-9845
http://hdl.handle.net/10347/14835
10.5424/fs/2015243-07865
Forest management
Biomass
Seedling
Clon
Blue gum
Forest tool
EucaTool®, a cloud computing application for estimating the growth and production of Eucalyptus globulus Labill
oai:minerva.usc.es:10347/225852020-07-06T08:43:11Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Arellano Pérez, Stéfano
author
Vega, José Antonio
author
Rodríguez y Silva, F.
author
Fernández, C.
author
Vega Nieva, Daniel José
author
Álvarez González, Juan Gabriel
author
Ruiz González, Ana Daría
author
2017
Evaluar y cartografiar la severidad del fuego después de incendios forestales se ha convertido en una tarea esencial para abordar la rehabilitación urgente de áreas quemadas y mejorar la planificación de la gestión postincendio. Aunque en Galicia se produce el mayor número de incendios forestales en España, la información sobre la estimación de la severidad del fuego mediante índices de teledetección es escasa. En este estudio se comparan, por primera vez en esta región, las capacidades de dNBR (differenced Normalized Burn Ratio) y RdNBR (Relative difference Normalized Burn Ratio), obtenidos de imágenes Landsat 8, para el testado de dichos índices con mediciones de severidad del fuego en campo, siguiendo el protocolo de CBI (Composite Burn Index), en el incendio de Oia-O Rosal (Pontevedra) ocurrido en 2013. Los modelos desarrollados para estimar dNBR y RdNBR en función del CBI fueron similares, con un porcentaje de variabilidad explicada de un 69% y 73%, respectivamente. Estos modelos permitieron obtener unos nuevos intervalos de las clases de severidad de dNBR y RdNBR para el área incendiada. Aunque los dos índices tuvieron valores de precisión conjunta relativamente altos y semejantes (75% y 83%, respectivamente) para clasificar las áreas afectadas por diferentes niveles de severidad, RdNBR mostró una ligera ventaja sobre dNBR. Además, el mapa de severidad basado en dNBR presentó menos superficie quemada con alta severidad, en comparación con RdNBR, y lo contrario para moderada severidad. Con esta información se dispone de una primera herramienta para abordar la evaluación de las pautas espaciales de severidad en incendios de Galicia, aunque será necesario contar con nuevos datos antes de disponer de una herramienta operativa.
Fire severity evaluation and mapping following wildfire is an essential task for post-fire rehabilitation activities and forest management planning. For that purpose, some spectral indexes are used to quantify the changes caused by fire, being Landsat satellite one of the most frequently used. Even though Galicia is the Spanish region with the highest number of fires in the country, the information on fire severity estimation through satellite imagery is scarce. In the present study, the capacity of dNBR (differenced Normalized Burn Ratio) and RdNBR (Relative difference Normalized Burn Ratio), through Landsat 8 imagery processing, are compared for the first time in Galicia to test both indexes with field data following the methodology from CBI (Composite Burn Index) in Oia-O Rosal (Pontevedra) wildfire occurred in the summer of 2013. The results indicate that the models for dNBR and RdNBR estimation according to CBI were similar, explaining a 69 and 73% of variability, respectively. These models allow to obtain a new fire severity thresholds for dNBR and RdNBR for the burned area. Although, both indexes showed a similar and quite high overall accuracy in the classification of the different fire severity classes (75% y 83% for dNBR and RdNBR, respectively), RdNBR was slightly more accurate than dNBR. Additionally, the dNBR-based fire severity map significantly underestimated the high fire severity area, compared with RdNBR. Those preliminary results can be useful to evaluate fire severity spatial
distribution, in wildfires in Galicia although new data will be necessary before an operational tool to be available.
Arellano, S., Vega, J., Rodríguez y Silva, F., Fernández, C., Vega-Nieva, D., Álvarez-González, J., y Ruiz-González, A. (2017). Validación de los índices de teledetección dNBR y RdNBR para determinar la severidad del fuego en el incendio forestal de Oia-O Rosal (Pontevedra) en 2013. Revista de Teledetección, 0(49), 49-61. doi:https://doi.org/10.4995/raet.2017.7137
1133-0953
http://hdl.handle.net/10347/22585
10.4995/raet.2017.7137
1988-8740
Severidad del fuego
Índices espectrales
dNBR
RdNBR
Landsat 8
Incendios forestales
Galicia 2013
CBI
Fire severity
Spectral indexes
Forest fires
Validación de los índices de teledetección dNBR y RdNBR para determinar la severidad del fuego en el incendio forestal de Oia-O Rosal (Pontevedra) en 2013
oai:minerva.usc.es:10347/220442020-05-06T02:01:44Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Corral Rivas, Sacramento
author
Álvarez González, Juan Gabriel
author
Corral Rivas, José Javier
author
López Sánchez, Carlos Antonio
author
2015
The diameter distribution of 44 permanent plots (conifers and broadleaf trees) was modeled using the three-parameter Weibull and Johnson's SB probability density functions (PDFs) in Santiago Papasquiaro, Durango. Four different methods of fitting parameters were used: maximum likelihood (ML), moments (MM), non-linear regression by ordinary least squares (ONLS) and percentiles (MP). The best method of fitting parameters for conifers and broadleaf trees was the method of moments. In modeling the Weibull PDFs, it was assumed that the location parameter (ε) corresponds to the minimum measurable diameter. The scale parameter (λ) was modeled using the method of prediction parameter (PPM) through a linear regression relating to the quadratic mean diameter and dominant height of the stand. Finally, the shape parameter (γ) was indirectly recovered by the method of moments through prediction of the average diameter of the stand. According to the Kolmogorov-Smirnov test (P= 0.05), 71 % of the plots for the group of conifers and 68 % of the plots for the group of broadleaf species come from a population that follows the fitting distribution function
La distribución diamétrica de 44 parcelas permanentes (coníferas y latifoliadas) se modeló a través de las funciones de densidad de probabilidad (FDP) Weibull de tres parámetros y SB Johnson, en el municipio de Santiago Papasquiaro, Durango. Para ello, se emplearon cuatro métodos de ajuste de parámetros: máxima verosimilitud, momentos, regresión no lineal por mínimos cuadrados ordinarios y percentiles. El mejor método de ajuste para las especies de coníferas y latifoliadas fue el método de momentos. En el modelado de la FDP Weibull se asumió que el parámetro de localización (ε) corresponde al diámetro mínimo inventariable de la distribución. El parámetro de escala (λ) se modeló con el procedimiento de predicción de parámetros a través de un modelo de regresión lineal simple que relaciona γ con el diámetro cuadrático medio y la altura dominante del rodal. Finalmente, el parámetro de forma (γ) fue recuperado indirectamente por el método de momentos a través de la predicción del diámetro medio del rodal. De acuerdo con la prueba de Kolmogorov-Smirnov (P = 0.05), 71 % de las parcelas del grupo de especies de coníferas y 68 % de las parcelas del grupo de latifoliadas provienen de una población que sigue la función de distribución ajustada
Corral-Rivas, Sacramento, Álvarez-González, Juan G., Corral-Rivas, José J., & López-Sánchez, Carlos A.. (2015). Characterization of diameter structures of natural forests of northwest of Durango, Mexico. Revista Chapingo serie ciencias forestales y del ambiente, 21(2), 221-236. https://dx.doi.org/10.5154/r.rchscfa.2014.10.046
2007-3828
http://hdl.handle.net/10347/22044
10.5154/r.rchscfa.2014.10.046
2007-4018
Conifers
Broadleaf trees
Weibull function
Distribution modeling
Coníferas
Latifoliadas
Función Weibull
Modelado diamétrico
Characterization of diameter structures of natural forests of northwest of Durango, Mexico
oai:minerva.usc.es:10347/37932022-07-04T12:20:56Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_3770com_10347_250com_10347_2956col_10347_10081col_10347_3773col_10347_9747
00925njm 22002777a 4500
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Marey Pérez, Manuel Francisco
author
Fernández Alonso, Sergio
author
Crecente-Maseda, Rafael
author
2006
Gestión integral y uso múltiple del territorio son
conceptos cada vez más presentes en la ordenación
forestal, y en las distintas figuras de ordenación territorial y
planeamiento sectorial. En España, hasta la fecha, la
normativa e instrumentos de ordenación territorial, de
concepción sesgadamente urbanística, han resultado muy
poco aplicables a los espacios forestales. Sólo a partir de la
Ley de Montes 43/2003 los planes tácticos de gestión
forestal adquieren más y más importancia en España,
siendo designados como Planes de Ordenación de
Recursos Forestales (PORF) y que, según esta ley, “…han
sido creados como instrumentos de planificación forestal
integrados en el marco de la ordenación del territorio, y su
ámbito de aplicación serán los territorios forestales con
características geográficas, socioeconómicas, ecológicas o
culturales homogéneas, de extensión superior al monte e
inferior a la provincia”. En el caso de Galicia, la unidad
forestal que cumple estos requisitos es el Distrito Ambiental.
En este artículo se expone la metodología que ha sido
desarrollada para la elaboración de este tipo de planes en
Galicia y su aplicación en la redacción del plan de un Distrito
Ambiental concreto: el Distrito Ambiental I, Ferrol.
1885-5547
http://hdl.handle.net/10347/3793
Gestión forestal sostenible
Uso múltiple del territorio
Planificación forestal estratégica
Forest management
Multiple uses on forest land
Strategic forest planning
Planificación forestal táctica y ordenación territorial: planes de ordenación de los recursos forestales, una aplicación en el distrito ambiental I de Galicia (España)
oai:minerva.usc.es:10347/216152023-07-10T06:18:07Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
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Gorgoso Varela, José Javier
author
Rojo Alboreca, Alberto
author
2014
Aim of study: In this study we compared the accuracy of the Weibull and the Johnson’s SB functions for describing diameter distributions in pedunculate oak (Quercus robur L.) and birch (Betula pubescens Ehrh.) stands.
Area of study: Galicia (Northwest Spain).
Material and Methods: A total of 172 diameter distributions in pedunculate oak and 202 in birch stands were finally evaluated. We compared the accuracy of three commonly used estimation methods of the Weibull and four estimation methods of the Johnson’s SB functions for describing these diameter distributions.
Main results. For Quercus robur L. stands, the most suitable methods were the Percentiles followed by Maximum Likelihood for the Weibull PDF and the method of Moments for the Johnson’s SB PDF. For Betula pubescens Ehrh. stands, the best fits obtained with the Percentiles and Maximum Likelihood methods were also superior to the method of Moments, whereas the Conditional Maximum Likelihood and method of Moments provided the best results for the Johnson’s SB PDF, depending on the statistic and the value of the location parameter considered.
Research highlights: Both distributions were suitable. The results were better for pedunculate oak than for birch stands.
Gorgoso Varela, José Javier, Rojo Alboreca,Alberto. (2014). Short Communication. A comparison of estimation methods for fitting Weibull and Johnson’s SB functions to pedunculate oak (Quercus robur) and birch (Betula pubescens) stands in northwest Spain. "Forest Systems", Vol. 23, n.3 p. 500-505
2171-5068
http://hdl.handle.net/10347/21615
10.5424/fs/2014233-04939
2171-9845
Knoebel and Burkhart
Location parameter
Percentiles
Maximum likelihood
Moments
Mode
Short Communication. A comparison of estimation methods for fitting Weibull and Johnson’s SB functions to pedunculate oak (Quercus robur) and birch (Betula pubescens) stands in northwest Spain
oai:minerva.usc.es:10347/212152020-04-08T02:00:46Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
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Arellano Pérez, Stéfano
author
Álvarez González, Juan Gabriel
author
Castedo Dorado, Fernando
author
Ruiz González, Ana Daría
author
González Ferreiro, Eduardo Manuel
author
2019
La altura de la base de la copa, la carga de combustible disponible y la densidad aparente son
características estructurales del dosel de copas utilizadas para predecir la actividad de fuego de copas. La
medición directa en campo de estas variables es impráctica y por tanto sus valores se estiman habitualmente
mediante el empleo de modelos predictivos. Avances en la modelización del comportamiento del fuego hacen que
sea de gran interés explorar la posibilidad de estimar de forma precisa y a escala de paisaje la distribución vertical
de los combustibles en el dosel de copas. En este sentido, este estudio pretende analizar el potencial de los datos
obtenidos de sensores LiDAR (Light Detection and Ranging) aerotransportados para modelizar dicha distribución
vertical en masas de pino silvestre en Galicia. Para ello se usaron datos del vuelo LiDAR del PNOA (Plan Nacional
de Ortofotografía Aérea) con una densidad de 0,5 primeros retornos m–2 y datos de campo procedentes del Cuarto
Inventario Forestal Nacional (IFN4). En un primer paso, la distribución vertical fue caracterizada empleando la
función de densidad de probabilidad de Weibull para, en un segundo paso, ajustar un sistema de ecuaciones
que relacionan las variables del dosel con métricas derivadas de los datos LiDAR. Las ecuaciones se ajustaron
simultáneamente para corregir los posibles problemas de correlación entre errores. Las distribuciones verticales
finalmente estimadas explicaron el 41% de la variabilidad observada en las parcelas de estudio. El sistema de
ecuaciones propuesto puede ser usado también para evaluar la efectividad de diferentes alternativas de gestión
del combustible para reducir el riesgo de fuego de copa en rodales de pino silvestre.
Canopy fuel load, canopy bulk density and canopy base height are structural variables used to predict
crown fire initiation and spread. Direct measurement of these variables is not functional, and they are usually
estimated indirectly by modelling. Advances in fire behaviour modelling require accurate and landscape scale estimates of the complete vertical distribution of canopy fuels. The goal of the present study is to model the
vertical profile of available canopy fuels in Scots pine stands by using data from the Spanish national forest
inventory and low-density LiDAR data (0.5 first returns m–2) provided by Spanish PNOA project (Plan Nacional
de Ortofotografía Aérea). In a first step, the vertical distribution of the canopy fuel load was modelled using the
Weibull probability density function. In a second step, a system of models was fitted to relate the canopy variables
to Lidar-derived metrics. Models were fitted simultaneously to compensate the effects of the inherent cross-model
correlation between errors. Heteroscedasticity was also analyzed, but correction in the fitting process was not
necessary. The estimated canopy fuel load profiles from LiDAR-derived metrics explained 41% of the variation in
canopy fuel load in the analysed plots. The proposed models can be used to assess the effectiveness of different
forest management alternatives for reducing crown fire hazard.
Fidalgo-González, L., Arellano-Pérez, S., Álvarez-González, J., Castedo-Dorado, F., Ruiz-González, A., & González-Ferreiro, E. (2019). Estimation of the vertical distribution of the fine canopy fuel in Pinus sylvestris stands using low density LiDAR data. Revista de Teledetección, 0(53), 1-16. doi:https://doi.org/10.4995/raet.2019.11241
1133-0953
http://hdl.handle.net/10347/21215
10.4995/raet.2019.11241
1988-8740
Carga de combustible disponible en el dosel de copas
Altura de la base de la copa
Densidad aparente de las copas
LiDAR aerotransportado
Fuego de copas
Canopy fuel load
Canopy base height
Canopy bulk density
Airborne laser scanning
Crown fires
Estimación de la distribución vertical de combustibles finos del dosel de copas en masas de Pinus sylvestrisempleando datos LiDAR de baja densidad
oai:minerva.usc.es:10347/219002023-07-10T06:18:15Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227col_10347_10081
00925njm 22002777a 4500
dc
Siqueira, Glécio Machado
author
Dafonte Dafonte, Jorge
author
Valcárcel Armesto, Montserrat
author
2015
El objetivo de este trabajo fue evaluar la ecología y la correlación lineal y espacial
entre malas hierbas de una pradera y su relación con la conductividad eléctrica aparente del
suelo (CEa, mS m-1). La toma de muestras se hizo los días: 23/06/2008 (CEa) y el 24/06/2008 (malas hierbas). Los datos fueron analizados por medio de estadística clásica y de herramientas de geoestadística. La mayoría de los datos presentaron distribución de
frecuencia logarítmica, siendo necesaria la utilización del krigeado residual. Se encontraron
bajos valores de correlación para las medidas de CEa con las mediciones de malas hierbas en el área de estudio, estando las mismas influidas por el relieve del área. Los mapas de
variabilidad espacial mostraron que existía relación entre las malas hierbas y los valores de
CEa (CEa-V y CEa-H), principalmente con relación al número de especies de malas hierbas, ya que hay un aumento del número de especies cuando se produce disminución de los valores de CEa. Los mapas de variabilidad espacial para las malas hierbas demuestran la dominancia de ciertas especies y el endemismo de otras
The objective of this study was to evaluate the ecology and, linear and spatial correlation
between weeds in and soil apparent electrical conductivity (ECa, mS m-1) in a
grassland. Measurements were done in 23/06/2008 (ECa) and 24/06/2008 (weeds). Data were analyzed using classical statistical and geostatistical tools. Most data presented logarithmic frequency distribution, using the residual kriging being necessary. Low values of correlation measures ECa measurements with weeds in the study area were found, being influenced by the topography of the area. The spatial variability maps have showed relationship between weeds and values of ECa (ECa-V and ECa-H), mainly regarding the number of weed species, as there are an increasing number of species with declining ECa values. The maps of spatial variability for weeds demonstrate the dominance of species and endemism of other species
SIQUEIRA, G.M., DAFONTE DAFONTE, J., & VALCÁRCEL ARMESTO, M.. (2015). CORRELACIÓN ESPACIAL ENTRE MALAS HIERBAS EN UNA PRADERA Y SU RELACIÓN CON LA CONDUCTIVIDAD ELÉCTRICA APARENTE DEL SUELO (CE A ). Planta Daninha, 33(4), 631-641. https://dx.doi.org/10.1590/S0100-83582015000400002
0100-8358
http://hdl.handle.net/10347/21900
10.1590/S0100-83582015000400002
1806-9681
Geoestadística
Atributos biológicos del suelo
Variabilidad espacial
Manejo del suelo
Manejo de praderas
Geostatistics
Soil and biological attributes
Spatial variability
Soil management
Grassland management
Correlación espacial entre malas hierbas en una pradera y su relación con la conductividad eléctrica aparente del suelo (CE A )
oai:minerva.usc.es:10347/162782022-11-14T13:55:19Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_2917com_10347_2891com_10347_3770com_10347_250col_10347_10081col_10347_11706col_10347_16274
00925njm 22002777a 4500
dc
Corbelle Rico, Eduardo José
author
Vila García, David
author
Crecente Maseda, Rafael
author
Díaz-Fierros Viqueira, Francisco
author
2014
Neste traballo descríbese o proceso de
preparación e posta a disposición do público da versión
dixital do Mapa de Capacidade Produtiva dos Solos de
Galicia, publicado orixinalmente en papel no ano 1984 baixo
a dirección de Francisco Díaz-Fierros Viqueira e Fernando
Gil Sotres. No momento de cumprir trinta anos desde a súa
publicación, este mapa constitúe aínda o único traballo de
avaliación da capacidade produtiva da terra con cobertura
completa do territorio de Galicia. Con todo, as limitacións
derivadas do formato en papel dificultaban
considerablemente o seu uso. Confiamos en que a versión
dixital que presentamos permita solventar parte destes
problemas e ampliar o seu coñecemento e utilización entre
a comunidade científica e técnica. Ao longo do texto trátase
de situar en contexto a importancia do mapa orixinal e as
razóns que motivaron a súa dixitalización, explicar o
proceso seguido para a preparación da versión dixital,
proporcionar información básica necesaria para futuros
usuarios non familiarizados coa fonte orixinal, e finalmente
presentar algúns datos resumo derivados do produto obtido
This paper describes the process of preparation
and publication of a digital version of the Map of Soil
Capability of Galicia, originally published as a book in 1984
by Francisco Díaz-Fierros Viqueira and Fernando Gil
Sotres. Although thirty years have passed since its
publication, this map still stands as the only available source
about soil capability covering the whole territory of Galicia.
Nevertheless, limitations imposed by the original publication
format (hardcopy) posed a significant obstacle for its use.
We believe that the digital version presented in this paper
will help users to overcome part of these shortcomings and
allow the map to be used by a wider cross-section of the
scientific and planning communities. This text is aimed to
place the map in context, expand on the reasons for the
preparation of a digital version, explain the procedures
followed in the process, provide basic information for its
future users, and present some summarizing data
processed from the final product
Corbelle Rico, E., Vila García, D., Crecente Maseda, R., & Díaz-Fierros Viqueira, F. (2014). Dixitalización do Mapa de capacidade produtiva dos solos de Galicia. Recursos Rurais, 10, pp. 35-43. Recuperado de http://www.usc.es/revistas/index.php/rr/article/view/3321
http://hdl.handle.net/10347/16278
2255-5994
Mapa de solos
Capacidade produtiva
Sistemas de información xeográfica
Ordenación territorial
Galicia
Soil maps
Soil capability
Geographic information systems
Planning
Dixitalización do Mapa de capacidade produtiva dos solos de Galicia
oai:minerva.usc.es:10347/240332023-07-10T06:21:34Zcom_10347_2916com_10347_2891com_10347_2888com_10347_227com_10347_2954com_10347_2893col_10347_12324col_10347_10081
00925njm 22002777a 4500
dc
Alonso Rego, Cecilia
author
Arellano Pérez, Stéfano
author
Cabo, Carlos
author
Ordóñez, Celestino
author
Álvarez González, Juan Gabriel
author
Díaz Varela, Ramón Alberto
author
Ruiz González, Ana Daría
author
2020
Forest fuel loads and structural characteristics strongly affect fire behavior, regulating the rate of spread, fireline intensity, and flame length. Accurate fuel characterization, including disaggregation of the fuel load by size classes, is therefore essential to obtain reliable predictions from fire behavior simulators and to support decision-making in fuel management and fire hazard prediction. A total of 55 sample plots of four of the main non-tree covered shrub communities in NW Spain were non-destructively sampled to estimate litter depth and shrub cover and height for species. Fuel loads were estimated from species-specific equations. Moreover, a single terrestrial laser scanning (TLS) scan was collected in each sample plot and features related to the vertical and horizontal distribution of the cloud points were calculated. Two alternative approaches for estimating size-disaggregated fuel loads and live/dead fractions from TLS data were compared: (i) a two-steps indirect estimation approach (IE) based on fitting three equations to estimate shrub height and cover and litter depth from TLS data and then use those estimates as inputs of the existing species-specific fuel load equations by size fractions based on these three variables; and (ii) a direct estimation approach (DE), consisting of fitting seven equations, one for each fuel fraction, to relate the fuel load estimates to TLS data. Overall, the direct approach produced more balanced goodness-of-fit statistics for the seven fractions considered jointly, suggesting that it performed better than the indirect approach, with equations explaining more than 80% of the observed variability for all species and fractions, except the litter loads
Alonso-Rego, C.; Arellano-Pérez, S.; Cabo, C.; Ordoñez, C.; Álvarez-González, J.G.; Díaz-Varela, R.A.; Ruiz-González, A.D. Estimating Fuel Loads and Structural Characteristics of Shrub Communities by Using Terrestrial Laser Scanning. Remote Sens. 2020, 12, 3704
http://hdl.handle.net/10347/24033
10.3390/rs12223704
2072-4292
Live/dead fuel fractions
Shrub cover
Shrub height
Litter depth
Simultaneous fitting
Fuel load additivity
Stand level equations
Estimating Fuel Loads and Structural Characteristics of Shrub Communities by Using Terrestrial Laser Scanning
oai:minerva.usc.es:10347/178712023-07-10T06:17:32Zcom_10347_2954com_10347_2893com_10347_2888com_10347_227com_10347_15613com_10347_15468col_10347_10081col_10347_15615
00925njm 22002777a 4500
dc
Gorgoso Varela, José Javier
author
García Villabrille, Juan Daniel
author
Rojo Alboreca, Alberto
author
2015
Methods of estimating extreme height values can be used in forest modeling to improve fits to the marginal distribution of heights in the following bivariate diameter-height models: the SBB Johnson’s distribution, the bivariate beta (GDB-2) distribution, the bivariate Logit-Logistic (LL-2) distribution and the power-normal (PN) distribution. Some applications to LiDAR derived data are also possible, e.g., for error calibration. Practical applications in forest management may also be considered, e.g., for pruning. In probability theory and statistics, the generalized extreme value (GEV) distribution, also known as the Fisher-Tippett distribution, is a family of continuous probability distributions that combine the Gumbel, Fréchet and Weibull distributions. This study compared the three distributions for fitting extreme values of tree heights (maximum and minimum heights), which were measured in 185 permanent research plots in Pinus pinaster Ait. stands, 97 research plots in Pinus radiata D. Don stands, and 128 research plots in Eucalyptus globulus Labill. Most of the eucalyptus stands were measured three times giving a total of 304 measurements. All plots are located in northwestern Spain. The Bias, Mean Absolute Error (MAE) and Mean Square Error (MSE) of the mean relative frequency of trees were used to evaluate the goodness-of-fit of the different functions, as well as the Kolmogorov-Smirnov statistic Dn. The Gumbel and the Weibull cumulative distribution functions (CDFs) proved suitable for describing extreme values of height distributions of the above-mentioned tree species in northwestern
Spain. The Fréchet distribution was only used to model maximum values and yielded the poorest results in all cases
Gorgoso-Varela JJ, García-Villabrille JD, Rojo-Alboreca A ( 2015 ). Modeling extreme values for height distributions in Pinus pinaster, Pinus radiata and Eucalyptus globulus stands in northwestern Spain. iForest 9: 23-29 . – doi: 10.3832/ifor1447-008 [online 2015-07-25 ]
1971-7458
http://hdl.handle.net/10347/17871
10.3832/ifor1447-008
Gumbel
Fréchet
Weibull
Minimum Height
Maximum Height
Modeling extreme values for height distributions in Pinus pinaster, Pinus radiata and Eucalyptus globulus stands in northwestern Spain
marc///col_10347_10081/100