Empirical analysis of the fragility of the physical environment in the municipality of Piquete-SP

Abstract

Alterations in land use caused by anthropogenic activities change natural dynamics and intensify natural processes such as water erosion. Considering this, this work aims to characterize the environmental fragility of the municipality of Piquete, state of São Paulo, by means of weights analysis using QGIS software. To this end, we adapted the empirical fragility method proposed by Ross (1994). A simple multicriteria analysis was carried out to classify and ascribe weights of equal importance to each variable observed, such as slope, land use and pedology, to create maps of both potential and emerging fragility in the region. These maps showed the locations that had greater and lesser susceptibility to erosive processes of soil loss, which were categorized into five classes, from very low to very high fragility. It was found that the most vulnerable classes occurred in areas with steeper slopes associated with more susceptible soils and higher weights regarding land use. In these areas it was possible to observe linear erosion in several places, corroborating the research hypothesis. Such results, together with the applied methodology, proved to be relevant for understanding and for an efficient environmental management, since anthropogenic activities have direct impacts on the fragility of the landscape.