干旱区生态环境知识资源中心

The watershed of the Pilon River is important for its water capture for commercial agriculture and for the conservation of the biological diversity of Nuevo Leon state. However, the magnitude of the forest and shrub fragmentation has not been determined, and the remaining fragments of higher conservation priority have not been identified. This study evaluates the vegetation fragmentation, using the fragment size and the relation between the perimeter and the fragment area (P/A) as indicators of size and shape, as well as the distance to the nearest neighbor and the intersection index and juxtaposition as connectivity indicators. These indicators were calculated in maps generated through satellite images Landsat of 1974 and 2000 interpretation (classification supervised and stratified). The results show statistically significant changes in the size and shape of fragments as well as in connectivity for all plant communities evaluated. The communities more affected by fragmentation in their size and shape were Abies and Oak forests, as well as the huizachal (Acacia scrub), piedmont scrub and pine forest. In its connectivity, fragmentation was more severe for Tamaulipan thorn scrub, piedmont scrub and desert scrub as well as huizachales. The fragments with higher priority conservation were determined considering their functions as buffer zones and as vegetation for slope stabilization, through the criteria application in a geographical information system, The conservation of 347 fragments for buffer zone and 210 fragments for slopes stabilization is recommended.