Abstract

VILLAVICENCIO GARCIA, Raymundo et al. Fragmentation effect upon natural regeneration in Sierra de Quila, Jalisco State. Rev. mex. de cienc. forestales [online]. 2012, vol.3, n.11, pp.09-24. ISSN 2007-1132.

In order to assess the composition, abundance and richness of natural regeneration in relation to open and closed pine-oak forest in regard to fragments of different sizes of open and closed canopy pine-oak forests, forest patches were defined using a digital vegetation map and a geographic information system. Upon Sierra de Quila protected area (141 km²), 85 concentric sampling plots of 500 and 100 m² were established for the inventory of adult trees and natural regeneration. According to fragment size, in the open forest were found from 7 to 14 species, and 855 as average number of seedlings per hectare in fragments from 10 to 50 ha and 3,065 trees in fragments over the last size; whereas, in closed forest, from 14 to 18 taxa were found and 4,060 young trees in 10 to 50 ha plots and 1,229 fragments in the area over 50 ha, which showed the highest diversity numbers. Richness of species diminishes in both types and fragment sizes. It is suggested to include in the conservation and management program for the protected area, as a priority action, to increases the connectivity between the fragments through propagation programs with native species and reforestation or other activities in regard to the conservation and restoration of forest cover.

Keywords : Composition; diversity; fragmentation; Pinus; Quercus; natural regeneration.