Tree species richness and diversity of the seasonally dry forest in Central Depression of Chiapas

Abstract

Se considera que Chiapas es la segunda entidad federativa de México con mayor diversidad fl orística (Breedlove, 1981), aunque regiones como la Depresión Central (DCCh) no han sido completamente descritas en su composición fl orística y estructura (Reyes-García y Sousa, 1997). Histórica-mente la vegetación dominante en la región corresponde a la del Bosque Tropical Caducifolio (BTC, sensu Rzedowski, 1978) Resumen: Se evaluó la diversidad de árboles contenida en 96 parcelas circulares de 0.1 ha, distribuidas en un intervalo altitudinal entre 441 y 1,740 m en la Depresión Central de Chiapas. Las parcelas se clasifi caron mediante un análisis de agrupamiento jerárquico y se ordenaron a lo largo de un gradiente ambiental por medio de un análisis de escalamiento multidimensional no métrico (NMDS). La clasifi cación permitió reconocer cinco asociaciones vegetales, tres de ellas correspondientes al bosque tropical caducifolio (BTC) y dos a los bosques de Quercus. La riqueza regional está representada por un total de 233 especies, en 152 géneros y 57 familias botánicas. La contribución de las parcelas a la diversidad total fue mayor en las asociaciones del bosque tropical caducifolio que en las de Quercus. La composición de especies estuvo dominada por individuos de etapas sucesionales tardías en las asociaciones del BTC (40-56%), en tanto que en los bosques de Quercus la mayor contribución fue de especies secundarias (46-54%). La ordenación (NMDS) mostró una relación signifi cativa de las parcelas con 10 de 12 variables climáticas, de las cuales el promedio anual de la temperatura media del mes más caliente (r 2 = 0.74, P <0.001) y la precipitación media anual (r 2 = 0.85, P<0.001) fueron las más importantes. A pesar de que en la Depresión Central de Chiapas persiste menos del 2% de la cobertura forestal, la diversidad de árboles es relativamente alta, debido a la heterogeneidad ambiental que promueve el recambio de especies a nivel regional. Palabras clave: Asociaciones vegetales, heterogeneidad, evapotranspiración real, Quercus NMDS, sucesión ecológica.Abstract: Tree diversity in the Central Depression of Chiapas was evaluated through 96 circular plots (0.1 ha each) distributed along to altitudinal range between 441 and 1740 m. Hierarchical cluster analysis helped to identify fi ve plant associations; three of them corresponds to the tropical dry forests (TDF), and two Quercus forest. Regional richness included a total of 233 species, 152 genera and 57 botanical families. The contribution of local plots to the total diversity was highest in the TDF associations than in the Quercus forest associations. Species composition was dominated by individuals of late successional stages in the TDF (40-56%), while greatest contribution was secondary species in the Quercus forests (46-54%). Ordination showed a signifi cant correlation plots with 10 of 12 climatic variables, which the average annual mean temperature of warmest month (r 2 = 0.74, P <0.001) and mean annual precipitation (r 2 = 0.85, P <0.001) were the most importa...

Applying a floristic originality index in tropical forests of south Sinaloa, Mexico

“…The floristic inventory shows that the Region of Palmito de Verde follows a pattern similar to others sites in Mexico, in relation to the more abundant families. The family Fabaceae usually is the most common in dry and semideciduous forest in the country (Lott et al 1987;Gentry 1995;Zamora-Crescencio et al 2008;Rocha-Loredo et al 2010;Gutiérrez-Báez et al 2011;Gutiérrez-Báez et al 2012;León-de la Luz et al 2012;Dzib-Castillo et al 2014;Méndez-Toribio et al 2014;Bravo-Bolaños et al 2016;Gutiérrez-Báez et al 2016;Gutiérrez-Báez et al 2017;Zamora-Crescencio et al 2017). In relation to Mangroves, this information only reinforces what has already been published by Blanco y-Correa Magallanes (2011).…”

Tree structure and composition of the secondary tropical deciduous forest in the Central Depression, Chiapas, Mexico

“…The forests of 19 years and 35 years of abandonment were dominated by the heliophilous species T. stans and M. tomentosa. In contrast, the older age condition was dominated by late species belonging to the genera Eugenia and Machaerium, recorded by Rocha et al [28] for the Central Depression.…”

“…Similar results have been recorded in other Neotropical secondary forests, suggesting that species composition recovery in these forests changes slowly over time [9,13,52] . Although the recovery rates of species composition of new assemblages are attributed to the availability of seeds from remnant vegetation [11] , disturbance is also an important factor that has led to variations in environmental conditions that influence the recovery rates of species in the study area [28] . Likewise, the similarity of species between conditions of longer time of abandonment can be explained due to the proximity between the sampled sites [53] .…”

“…The few studies conducted particularly in secondary forests record a species richness between 119 and 157 tree species in fragments with lower levels of disturbance [26,27] . Meanwhile, the floristic composition of the less disturbed remnants is confirmed by late tree species, whose assemblages change due to the combined effect of environmental heterogeneity and anthropogenic disturbance [28] . There are practically no studies available that document the ecological changes and processes of succession in the face of anthropogenic disturbance, which serve as a basis for understanding the phenomenon, planning conservation and restoration actions for the BTC in this region.…”