Identificação de áreas prioritárias para a recuperação da vegetação nativa, na Bacia do Rio Buranhém, com o auxílio da modelagem espacial multicriterial

Abstract

The suppression of native vegetation and their replacement by agricultural crops, among other land uses, can promote soil erosion and interference in the hydrological cycle of a watershed. However, some of these degraded areas are permitted to be used under environmental legislation, while there are areas that could not have been cleared due to the legal restrictions on use. It is important to know, then, how to identify which of these areas can be used and which need to be restored to their original vegetation. In this sense, the objective of this study was to apply Multicriteria Analysis techniques to identify the priority areas for the recovery of native vegetation, in the Buranhém watershed, located in the states of Minas Gerais and Bahia. Initially, it was necessary to delimit the hydrographic basin and identify its drainage network. For this purpose, the accuracy of the automatic delimitation methods was evaluated using digital elevation models (DEMs), and the results were compared with those obtained by manual vectoring. It was also made the identification of areas with restrictions on use and suppression of their native vegetation cover, such as the Permanent Preservation Areas (APPs) and Legal Reserve (RL), checking for land use conflicts. In addition to the APPs and RLs, eight other criteria were included in the spatial modeling, whose order of importance was established according to the weights obtained from the Analytical Hierarchical Process (AHP). The modeling was elaborated with map algebra techniques applied with the method of weighted linear combination (WLC), in a GIS environment, resulting in a synthesis map with the hierarchy of priority areas for recovery. The results presented in this study can assist competent institutions in investigating cases with evidence of non-compliance with environmental legislation, as well as assisting in the planning of river basins, optimizing the application of resources and efforts aimed at the recovery of priority degraded areas