Vulnerabilidad ambiental en cuencas hidrográficas serranas mediante SIG

summary soil degradation is increased by the presence of environmental risks, as a conjunction of an extreme natural phenomenon and the anthropogenic actions, within a certain time and space. the aim of this work was to delimit the environmental vulnerability in rangeland watersheds, using a gis. the area of study was the upper watershed of the sauce grande river, in the southwest of buenos aires, argentina. the cartographic model consisted of maps that were processed in order to represent the conditioner and activator factors, by the assignment of integer numeric codes to the different categories of each thematic layer, which were joined in order to obtain a unique value. the methodology used was qualitative and additive. the environmental susceptibility was defined using a combination of conditioner factors. the modified fournier index (mfi) was used to determine the activator factor, establishing its aggressiveness and spatial variation. the results allowed us to obtain a cartographic database for the delimitation of the environmental vulnerability.