Potencial natural de erosão e limite de tolerância de perdas de solo na Bacia Hidrográfica do Açude do Namorado.

Abstract

Knowing a watershed, especially if it has a semi-arid climate, is of fundamental importance for the management and planning of water resources; as well as to assist in the monitoring of indicators aiming to guide actions for the protection, recovery and promotion of the sustainable use of terrestrial ecosystems, guiding the sustainable management of forests, with measures to combat desertification, seeking to stop and reverse soil degradation and loss of biodiversity. In this context, the work estimated the soil loss tolerance limit and the natural erosion potential applied to the Namorado reservoir watershed in a semi-arid region, the methodology was adopted, where a digital mosaic of the SRTM was used for the elaboration of the slope map. of the quadrant, SB24ZD of the study area was used and from them the contour lines were generated. To generate the triangular grid, a database was created in the SPRING 5.2 program in the UTM/SAD69 projection; slicing of this grid was performed; with the establishment of slope class limits, using geoprocessing techniques and the algebraic language of SPRING for data modeling. The results portrayed with reasonable accuracy the current state of the lands in the basin and demonstrated that the tolerance limit for losses of very high class soils occurred in 95.38% of the basin associated with Luvisols, Vertisols, Planosols, Litholic Neosols and Fluvic Neosols. The natural erosion potential of the middle class basin ranged from 50 to 250 Mg ha-1 yr-1 in 63.89% of the area, influenced by the average slope in areas where Luvisols occur.