Document: RAF-3-67-21

Successional changes in a Mexican montane cloud forest (soil, vascular plants, non-vascular epiphytes and small mammals): Implications for management and conservation.

DECASTILLO, R.F.*, B.A.CRUZ, A.B.MACÍAS, M.A.BRIONES, J.S.CORDOVA, VHERNÁNDEZ, P.A.VELÁQUEZ and R.RIVERA

CIIDIR Oaxaca -Instituto Politécnico Nacional, Oaxaca 71230 México ¹

Abstract:
We studied the dynamics of succession using three chronosequences in Sierra Norte, Oaxaca, Mexico. The land was originally occupied by montane cloud forests, but, after clear cutting, maize cropping and abandonment, the land is a mosaic of croplands, secondary and primary forests. The following trends were observed with succession: 1) A change form forests dominated by conifers, where Pinacea and Compositae were most representative, to a forest dominated by hardwoods, mainly Fagaceae, Lauraceae, Theaceae, and Rhamnaceae; 2) an increase in soil acidity, and exchangeable Al; 3) a decrease in potential nitrification, and an increase in potential ammonification; 4) an increase in cover of non-vascular epiphytes, mainly mosses and liverworts; and 5) a decrease in small-mammal diversity (Didelphimorphia, Insectivora, and Rodentia). We also found little and non-significant changes in vascular plant richness; however, endangered, endemic or rare plants were more common in older forests. Therefore, preservation of older or primary forest of enough extension to keep viable their populations is crucial for conservation purposes, but it is also important to preserve certain extensions of secondary forests.

Keywords:

This abstract is being presented at: 3:30 PM in session:
Poster Session #17: Vegetative Analysis.