Browsing by Author "Gilabert, Horacio"

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    Allometric Models for Estimating Aboveground Biomass in Short Rotation Crops of Acacia Species in Two Different Sites in Chile
    (MDPI, 2021) Cabrera Ariza, Antonio; Valdes, Sara; Gilabert, Horacio; Santelices Moya, Romulo Eduardo; Alonso Valdes, Maximo
    We evaluated the ability of different allometric models to estimate the biomass production of short-rotation woody crops of Acacia dealbata, A. mearnsii and A. melanoxylon. Models considered the adjustment and validation of biomass functions and biological restrictions, such as the use of additive components of the biomass (stem, branches, and leaves). Adjustments of linear and nonlinear models of the three acacia species-established in two locations and of three densities in southern Chile-were utilized. Systems of equations were adjusted to guarantee the addition of the biomass components and the trees' total biomass. The selection of models was performed based on their goodness of fit and predictive quality. Methods that accounted for the correlation between biomass components granted an additively consistent equations system with efficient estimates and reliable prediction intervals.
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    Dinámica estacional y patrones de distribución de la avifauna asociada a humedales subantárticos de la Reserva de Biosfera Cabo de Hornos (54-55ºS), Chile
    (2009) Ibarra Eliessetch, José Tomás; Rozzi, Ricardo; Gilabert, Horacio; Anderson, Christoper B.; McGehee, Steven M.; Bonacic, Cristián
    El rol de las aves en la ecología de los ecosistemas subantárticos de la Reserva de Biosfera Cabo de Hornos (RBCH), Chile, ha sido poco estudiado. Se estudió el efecto de la altitud, distancia al borde costero, tamaño del espejo de agua, estación del año y cobertura vegetacional sobre la diversidad y abundancia de aves de humedales y de sus hábitats adyacentes en isla Navarino (54–55ºS, 67ºW) en la RBCH. Se cuantificó la composición específica, riqueza de especies y abundancias relativas de aves de humedales y de sus hábitats adyacentes, de manera estacional. Se registró un total de 56 especies pertenecientes a 10 órdenes y 25 familias, con una marcada estacionalidad en riqueza (P = 0,001) y número total de individuos (P < 0,01). De ellas, 33, 9% fueron residentes, 48,2% llegan en primavera-verano y para un 17,9% se desconoce su estacionalidad. La distancia a la costa marina es la variable que mejor explica tanto la riqueza (P < 0,01) como el número total de individuos (P < 0,05). Humedales a mayor distancia de la costa y altitud, presentaron menor diversidad de aves, a pesar de que los cambios en altitud fueron bajos (<300 m). Este trabajo muestra los patrones de estacionalidad y dinámica, así como los mecanismos subyacentes, de la avifauna de humedales y sus hábitats adyacentes en la RBCH. Aceptado el 20 de Mayo de 2009
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    Forest cover outside protected areas plays an important role in the conservation of the Vulnerable guina Leopardus guigna
    (2013) Galvez, Nicolas; Hernandez, Felipe; Laker, Jerry; Gilabert, Horacio; Petitpas, Robert; Bonacic Salas, Cristian; Gimona, Alessandro; Hester, Alison; Macdonald, David W.
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    Optimizing Inventory and Yield Data Collection for Forest Management Planning
    (OXFORD UNIV PRESS INC, 2010) Gilabert, Horacio; McDill, Marc E.
    This work uses a Cost+Loss approach to estimate the optimal investment in inventory information for forest planning A bootstrapping approach is used to simulate the impact of different inventory intensities on the quality of decisions in a linear programming harvest scheduling model Multiple formulations of the harvest model based on varying inventory intensities are used to calculate the value of a variable labeled Loss that measures the monetary losses resulting from the use of imperfect yield information in the harvest model The variable Loss and the cost of obtaining the inventory information are used to estimate empirical relationships between their expected value and the amount of inventory information (number of inventory plots and number of experimental plots) used in the harvest models These two relationships are combined to give an explicit estimate of the expected Cost+Loss as a function of the inventory intensity variables This Cost+Loss relationship is minimized to estimate optimal number of inventory plots and the optimal number of experimental plots An example is developed with radiata pine information from southern Chile Results for this example suggest that current practice uses too many experimental plots and too few inventory plots FOR SCI 56(6) 578-591
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    Territorios del Mañana. Modelos predictivos de capacidad de carga para la gestión sustentable de los territorios
    (Ril Editores, 2022) Moris Iturrieta, Roberto; Moris Iturrieta, Roberto; Gilabert, Horacio; Bergamini, Kay; Zaviezo, Daniela; Ángel, Piroska