Abstract

LOPEZ MARTINEZ, José Israel et al. Recovery of the tree stratum in a high mountain ecosystem affected by fire. Rev. mex. de cienc. forestales [online]. 2017, vol.8, n.41, pp.164-182. ISSN 2007-1132.

In order to evaluate the ecological recovery the floristic and horizontal structures of the arboreal vegetation impacted by fire in a high mountain forest ecosystem were compared. Two adjacent areas were considered; one impacted by fire and other not impacted. Under each zone five sampling units were established in the form of a conglomerate composed for four circular sites of 400 m2, where all tree were registered (DBH ≥ 7.5 cm). The vegetation at community level was characterized by the importance value index (IVI), a diametric categorization and the estimation of species richness and diversity using the Margalef (D Mg ) and Shannon (H') indices respectively. A statistical analysis of medians considering two variables of the floristic structure (Margalef index and Shannon index) and three of the horizontal structure (density, crown area and basal area) was performed. In both conditions, Pinus pseudostrobus was the most representative specie. The variables of the floristic structure (Margalef index and Shannon index) and density were not statistically different (p> 0.05), while in the horizontal structure, the values of the crown area and basal area were statistically different (p < 0.05). The results indicate that 19 years after the occurrence of the fire, the tree vegetation has a partial recovery.

Keywords : Pine-oak forest; species diversity; forest fires; Margalef index; Shannon index; species richness.