CONTRIBUTIONS TO THE HYDROGRAPHIC BASIN MANAGEMENT FROM THE MULTICRITERY APPROACH TO ANALYSIS OF ENVIRONMENTAL FRAGILITY TO EROSIVE PROCESSES

Abstract

One of the most important issues in the management of watersheds is the integration of spatial information aimed at understanding the anthropic pressures to which they are subjected. To this end, the use of Hierarchical Process Analysis (AHP) techniques through the use of Geographic
Information Systems (GIS) tools can contribute significantly to the proposal to develop policies
aimed at the conservation and preservation of the environment, especially forests and water resources. Thus, this article seeks to demonstrate the versatility and robustness in determining priority areas to protect the natural resources of Una River Hydrographic Basin (Ibiúna - São Paulo - Brazil) through spatial analysis techniques. For the development of the work, information related
to land use, relief slope, erosivity and soil erodibility were used, with the multicriterial technique of
AHP as an instrument of integration and analysis. The results showed that the watershed presented
15% of the areas with a high degree of impairment and 38.6%degree, corresponding to more than
53.6% of the total basin area under conditions considered undesirable. Most of these areas correspond to the presence of anthropic and agricultural areas, the main impacting factors of the
basin. From the results it can be concluded that the application of AHP was very useful in the development of work and that the products generated can serve as guidance to public managers in watersheds with the adoption of preventive conservation policies aimed at integrated management of river basins.