SIG na avaliação da erosão hídrica na bacia do Rio Capim, Pará.

Abstract

The transition from native vegetation to agricultural systems in the Amazon due to the intensification of agricultural activities has resulted in soil loss processes through water erosion. In the Capim River Basin, in the Eastern Amazon, agricultural activities occupy 44.33% of the land in the region, equivalent to 2,200,361 hectares, which may have their productive capacity reduced due to erosion. Mathematical models for estimating erosion are recognized as important tools for agricultural and environmental planning. The objective of this study was to estimate soil loss due to water erosion in the Capim River Basin, using the Revised version of the Universal Soil Loss Equation (EUPS). The study area is located in the Northeast region of the State of Pará and part of Maranhão and has an area of 37,262 km². The Variable R (Erosivity) was calculated through historical measurements from 2001 to 2021 at meterological stations throughout the studied Basin, while the LS variables were obtained using satellite images to determine the Digital Elevation Model (DEM). The K factor (Soil Erodibility) was determined from a literature review and the C.P factor was calculated through the preparation of the land use and occupation map. The results classify the erosion of the studied area as mild to moderate, with a soil loss value corresponding to 3.2318 t/ha.year, where the factors with the greatest contribution to this result are the Erodibility factors and the slope of the terrain. The identification of the different land uses made the C.P. Factor and the L.S. were decisive in identifying the southern and western regions as the most susceptible to erosion. It is believed that these results can guide the understanding of erosion processes in the Capim river basin, identifying the main anthropogenic interferences that enhance this process, as well as demonstrating the importance of planning land use and occupation and adopting appropriate management techniques. management aimed at sustainable land use.