Interrelated modeling of land use and habitat for the design of an ecological corridor : a case study in the Yungas, Argentina

This thesis aims at developing tools to mitigate the process of natural habitat fragmentation related to deforestation, which is becoming a crucial conservation issue in the Yungas, a mountain subtropical forest in the northwest of Argentina. The conservation of forest connections among protected areas is one of the principal targets of nature conservation action in the region, and therefore a major objective of our development. A multi-temporal approach to analyze the evolution of the land use and cover change (LUCC) is proposed. A spatially explicit quantitative analysis of the historical sequence of deforestation for the period 1973 - 2000 is presented. In this period, 80,000 ha have been deforested. This gives an actual indication of the intensity of the conversion of native forest into farmland (farmland area increased from 5 % to 11 % of the total region). A conceptual model depicting the main driving forces interacting from global to local level is formulated. A logistic regression analysis allowed the identification of the spatial determinants (as local proximate variables) for the location of possible future changes in land use. These variables (soil classes, accessibility, slope) were integrated using a GIS procedure that produced a LUCC probability spatial model. This has the principal purpose of predicting the location of future clearings.