ALBERT

Description: Soto A, Rodríguez-Martínez D, López De Heredia U SIMHYB: A SIMULATION SOFTWARE FOR THE STUDY OF THE EVOLUTION OF HYBRIDIZING POPULATIONS. APPLICATION TO QUERCUS ILEX AND Q. SUBER SUGGESTS HYBRIDIZATION COULD BE UNDERESTIMATED Abstract : We present SimHyb, a Java-based software for the simulation of mixed hybridizing populations. The software incorporates user-defined initial parameters and input files to account for the initial census size of two species in a closed population, the number of intermediate specific classes, the directional fertility among specific classes, the fitness coefficients for each specific class, the inheritance of fitness, and the degree of ageing and self-incompatibility of the individuals. All these demographic and adaptive parameters can be modified by the user to analyze their effect on the evolution of the mixed population. SimHyb allows the traceability of each individual, whose pedigree is also recorded. For each simulated generation the software yields an output file that is easily convertible to an input for Structure, one of the most popular softwares for the Bayesian analysis of populations. Application of SimHyb to simulate Quercus ilex and Q. suber hybridizing populations, and further analysis with Structure, reveals that advanced introgressed individuals are very often misclassified with the currently available set of nuclear microsatellite markers, so that introgression between these two species could have been underestimated in previous studies. However, we provide a simple parameter based on Structure results to identify the directionality of pollination in the progeny of a known mother tree. Keywords : Hybridization, Introgression, Simulations, Molecular Markers, Quercus suber, Quercus ilex iForest 11 (1): 99-103 (2018) - doi: 10.3832/ifor2569-011 http://iforest.sisef.org/contents/?id=ifor2569-011

Description: Minoche D, Risio-Allione L, Herrero De Aza C, Martínez-Zurimendi P DENSITY MANAGEMENT DIAGRAM FOR TEAK PLANTATIONS IN TABASCO, MEXICO Abstract : Density management diagrams are valuable tools for managing specific forest species. The aim of this study was to obtain a density management diagram for teak (Tectona grandis L.) plantations in the State of Tabasco in Mexico. To achieve this objective, a set of 10 plantations were studied, in which 42 plots were established. Two equations were fitted simultaneously, including one related to the quadratic mean diameter, stand density and dominant height and the other which related the total stand volume to the quadratic mean diameter, stand density and dominant height. The results showed that the diagram had an acceptable predictability, thus indicating its usefulness and accuracy in planning silvicultural interventions. This diagram is a very powerful tool that can enable stakeholders to manage teak plantations in the State of Tabasco. Keywords : Silvicultural Interventions, Stand Density Diagram, Quadratic Mean Diameter, Tectona grandis iForest 10 (6): 909-915 (2017) - doi: 10.3832/ifor2247-010 http://iforest.sisef.org/contents/?id=ifor2247-010

Description: Cruz-Huerta C, González-Guillén MDJ, Martínez-Trinidad T, Escalona-Maurice M IDENTIFYING PRIORITY CONSERVATION AREAS FOR ABOVE-GROUND CARBON SEQUESTRATION IN CENTRAL MEXICO Abstract : Identifying forest ecosystems with significant ecological, social, and/or economic values is an important first-step in conserving landscape function. Here, we identify priority conservation areas in the municipalities of Chignahuapan and Zacatlan, Puebla (Mexico), based on: (i) their capacity to sequester atmospheric CO2; and (ii) risk of future deforestation. We also explore management strategies for priority-lands conservation in the Mexican context. Above-ground C sequestration was estimated using wood density and biomass expansion-factor data available from local forestry sources. Deforestation risk was estimated by a probabilistic model of land use change using socioeconomic and biophysical variables. Carbon sequestration estimates ranged from 14 to 531 Mg ha-1 for Chignahuapan and Zacatlan, respectively. An estimated 11.746 and 4.406 ha of forest was determined to be at risk of deforestation in each municipality. Of these at-risk lands, 2.421 and 1.798 ha were determined to be at high risk. In combination, we determined that 10.687 and 4.319 ha, respectively, are priority lands for carbon sequestration in Chignahuapan and Zacatlan, of which 628 and 310 ha were determined to have high conservation priority. Identifying priority conservation areas through the integrated assessment of carbon sequestration and deforestation risk can enhance efforts to target land management strategies to mitigate climate change impacts. This approach can serve as a model for other forested regions in Mexico and other countries. Keywords : Forest Carbon Sinks, REDD, Climate Change, Deforestation Risk, Priority Conservation, Probabilistic Model, Land Use, Development iForest 10 (6): 923-929 (2017) - doi: 10.3832/ifor1980-010 http://iforest.sisef.org/contents/?id=ifor1980-010