ANALISIS ESTRUCTURAL DE UN ECOSISTEMA FORESTAL DE Pinus - Quercus EN LA SIERRA MADRE ORIENTAL

Abstract

The present methodology is a combination of the global measurement of the forest and the sampling analysis; the data of the total measurement of the population was used to determine the abundance (N/ha) and the dominance (G 1 .3/ha) of the arboreal individual species.The frequency of the different tree species was defined through the sampling unit, as well as the index of the diametric differentiation (TO), height (TH) and the mixture of speciés (DM). The height of the tree species was used to assess the index of vertical distribution. Results show that Pinus pseudostrobus is the species with greater presence in the pine-oak ecosystem; followed by Quercus rysophylla and Juniperus f/accida. According to the mingling index of species, this ecosystem has an irregular forest form since more than 50 percent of the population grows clase to sorne others species. The vertical distribution index of species describes the presence of 11 tree species distributed in three strata according to the height in the pine-oak ecosystem, being Pinus pseudostrobus the most outstanding, as it is found in three defined ·strata and in a greater proportion. The dimensionc;ll differentiation in diameter as well as in height of the zero trees and their closest neighbors in the pine-oak forest indicate that 70 per cent of the population shows a slight difference in both dimensions.