Environmental vulnerability to linear erosive processes in Brazilian Cerrado

Abstract

In recent decades, land use and cover by pasture and, more recently, by soybean cultivation, have intensified and/or triggered accelerated erosive processes in the Brazilian Cerrado. Thus, the aim of this study was to analyze the environmental vulnerability to linear erosive processes based on aspects of landform (compartments of relief and slope), soil, and land use and cover in a region of the Brazilian Cerrado, between 1985 and 2022. Mapping of environmental vulnerability to linear erosive processes was carried out in 1985 and 2022, based on the Analytic Hierarchy Process (AHP), fieldwork, and soil collection at three points, enabling identification of three levels of environmental vulnerability: low, medium, and high. Areas with low environmental vulnerability presented the smallest percentage area (15.10% in 1985 and 12.85% in 2022) and was related to flat tops of hills, remaining Cerrado vegetation of forest and savanna formations, and sandy soils. The medium environmental vulnerability showed an increase in area of ​​7.18% in the period analyzed and the main cause for this was deforestation for pasture and soybean plantations. The high environmental vulnerability was significant, with 47.09% and 42.16% of the total area in 1985 and 2022, respectively, and including areas of steep slopes, clayey and shallow soils, pasture, and exposed soil. Given these results, it is concluded that the various phytophysiognomies of the Cerrado are being deforested by anthropogenic activities, which are the main factor in accelerated erosion. Therefore, there is an urgent need to implement soil conservation techniques and recover degraded areas, in addition to more effective environmental management.