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Soria, Spain

Rodriguez F.,Cesefor Foundation | Peman J.,University of Lleida | Aunos A.,University of Lleida
Forest Ecology and Management | Year: 2010

Whole-stand models normally require data on initial stand basal area and dominant height. Dominant height measurements are time-consuming and often imprecise, compromising subsequent predictions. Poplar plantations provide a special case where basal area correlates with site index; a whole-stand model could thus be based on stand basal area. We report a static model constructed by the generalized algebraic difference approach (GADA) for poplar plantations for three different hybrid poplars (Populus × euramericana (Dode) Guinier "I-214", "MC", and "Luisa Avanzo") in northeast Spain. The transition function was based on current stand basal area and was fitted with data from 158 permanent plots ranging from 1- to 17-year-old plantations. Merchantable stand volume was estimated by a volume equation where height was predicted by a height-basal area relationship based on 458 temporary plots. The model differences between clones were compared using the nonlinear extra sum of squares method. Significant differences were detected, while Luisa Avanzo presented the highest merchantable volume at the end of the rotation. Errors in basal area predictions were below 20% within 6 years in the case of Luisa Avanzo and MC clones, and within 3 years in the case of I-214. Our research showed that satisfactory predictions can be obtained using GADA with a single transition function based on an easily measurable variable such as stand basal area. © 2010 Elsevier B.V. All rights reserved. Source


Rodriguez F.,Cesefor Foundation | Lizarralde I.,Cesefor Foundation | Bravo F.,University of Valladolid
Forest Science | Year: 2013

A system of additive equations was developed to predict whole-tree volume and the different components of Corsican pine. In this work, the nonlinear seemingly unrelated regression (NSUR) approach, which guarantees additivity in nonlinear equations, was evaluated. The effect of bark thickness on the accuracy of the results for all tree components was also assessed. Data for 351 trees, ranging in age from 10 to 72 years, were collected from 65 public and private sites. The volume estimates show average biases that range in absolute values from 2.19 to 31.02 dm3 for whole-tree, from 1.41 to 27.31 dm3 for wood, and from 1.05 to 16.52 dm3 for bark volume components. Errors in volume predictions were relatively small, representing less than 3% of the average observed wood volume and less than 6% of the average observed bark volume. This research showed that satisfactory predictions can be obtained from forcing additivity using NSUR approach with a minimal number of easily measurable tree variables, such as dbh and total height. © 2013 by the Society of American Foresters. Source


Gonzalez-Olabarria J.-R.,Center Tecnologic Forestal Of Catalonia Ctra St Llorenc Of Munys | Rodriguez F.,Cesefor Foundation | Fernandez-Landa A.,AGRESTA Sociedad Cooperativa | Fernandez-Landa A.,Technical University of Madrid | And 2 more authors.
Forest Ecology and Management | Year: 2012

The present study sets a methodological framework to combine LiDAR derived data with fire behaviour models in order to assess fire risk at landscape level for forest management and planning. Two forest areas of the Model Forest in Urbión, Soria (Central Spain) were analyzed, covering 992.7ha and 221.7ha. The modelling phase was based in 160 field sample plots as ground data, and the LiDAR data had a density of first returns of 2pulses/m 2, which were used to construct 13 models for stand variables (e.g. basal area, stem volume, branch biomass). The coefficients of determination ranged from 0.167 for shrub cover, to 0.906 for dominant height. The modelled variables were used for a classification of fuel types compatible with the continuous data. The simulation phase was performed using the spatialized data on FlamMap in order to assess the potential fire behaviour resulting across the whole landscape for four scenarios of moisture and wind conditions. The results showed maps of fire intensity and probability of fire occurrence, based on the simulation of 500 random ignition points, which allowed the analysis of the spatial relation between the initial state and allocation of forest resources and their risk of fire. The methodology proposed, as well as the results of this research are directly applicable for operational forest planning at landscape level. © 2012 Elsevier B.V. Source


Bravo F.,Sustainable Forest Management Research Institute UVa INIA | Bravo F.,University of Valladolid | Alvarez-Gonzalez J.G.,University of Santiago de Compostela | del Rio M.,Sustainable Forest Management Research Institute UVa INIA | And 32 more authors.
Forest Systems | Year: 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 modeling in Spain are presented. Source


Anttila P.,Finnish Forest Research Institute | Asikainen A.,Finnish Forest Research Institute | Laitila J.,Finnish Forest Research Institute | Broto M.,Cesefor Foundation | And 3 more authors.
Forest Systems | Year: 2011

Soria is a forested province in Northern Spain. The utilization level of the forests in Soria is low at present, but it is predicted to rise in the future. Because of the high altitude, heating is also needed. These form a good basis for increasing the use of wood chips in energy production. In this study, a procedure to estimate the potential of wood chip from forests and their procurement costs was adapted to Spanish conditions. The harvesting potential was estimated to be between 140,000 m 3 and 280,000 m 3 in 2010, and to double by 2030. Cost-supply curves were provided to aid in the planning of heating plant investments. Compared to European cost levels, the procurement costs in Soria are not high. Source

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