<Emphasis Type="Italic">β</Emphasis>-Diversity and vegetation structure as influenced by slope aspect and altitude in a seasonally dry tropical landscape |
| |
| Authors: | J Alberto Gallardo-Cruz Eduardo A Pérez-García Jorge A Meave |
| |
| Institution: | (1) Departamento de Ecología y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autónoma de México, Ciudad Universitaria, 04510 Mexico, DF, Mexico |
| |
| Abstract: | Topography strongly affects the distribution of insolation in the terrain. Patterns of incoming solar radiation affect energy
and water balances within a landscape, resulting in changes in vegetation attributes. Unlike other regions, in seasonally
dry tropical forest areas the potential contribution of topography-related environmental heterogeneity to β-diversity is unclear. In Mt. Cerro Verde (Oaxaca), S. Mexico, we: (1) modelled potential energy income for N- and S-facing
slopes based on a digital elevation model, (2) examined the response of vegetation structure to slope aspect and altitude
and (3) related variations in plant diversity to topography-related heterogeneity. Vegetation survey and modelling of potential
energy income (SOLEI-32 model) were based on 30 plots equally distributed among three altitudinal belts defined for each slope
of the mountain; combining the three altitudinal belts and the two slopes produced six environmental groups, represented by
five vegetation plots each. Potential energy income was about 20% larger on the S than on the N slope (9,735 versus 8,138 MJ/m2), but it did not vary with altitude. In addition, the temporal behaviour of potential energy income throughout the year differed
greatly between slopes. Vegetation structure did not show significant changes linked to the environmental gradients analysed,
but altitude and aspect did affect β-diversity. We argue that the classic model of slope aspect effect on vegetation needs reconsideration for tropical landscapes.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorised users. |
| |
| Keywords: | Environmental heterogeneity Oaxaca State Mexico Plant diversity Potential energy income modelling Seasonally dry tropical forest Topography Vegetation structure α -Diversity γ -Diversity |
| 本文献已被 SpringerLink 等数据库收录！ |
|
