Análise dos processos erosivos por meio do uso de modelagem e parcelas experimentais de pinos de erosão no alto curso do Arroio Quilombo (RS)

Abstract

Water erosion is one of the main processes of soil degradation, directly affecting the conservation of natural resources and the sustainability of agricultural activities. In the Pampa biome, increasing anthropic pressures on the land have raised the vulnerability of small watersheds, demanding a deeper understanding of erosive processes at different scales. This dissertation, entitled Analysis of erosive processes through modeling and experimental plots with erosion pins in the upper course of Arroio Quilombo (RS), complementing to evaluate the dynamics of water erosion in a representative watershed of the biome by integrating experimental approach and spatial modeling. Experimental plots with erosion pins were installed in areas under different land uses and covers, enabling direct quantification of soil losses and gains. Simultaneously, the Universal Soil Loss Equation (USLE) was applied, parameterized with edaphoclimatic, topographic, and land use information, in order to estimate the erosive susceptibility of the watershed. The results showed spatial agreement between the areas of greatest soil removal observed experimentally and those with the highest losses estimated by the EUPS, although the latter tended to overestimate the absolute loss values. The influence of vegetation cover and management practices on the intensification of erosion processes was highlighted. It was also observed that areas under agricultural use were more vulnerable to erosion, whereas those with natural vegetation cover acted as protective zones against soil loss and sedimentation of watercourses. The analysis indicated that agricultural areas were more vulnerable to erosion, while zones with preserved natural vegetation acted as protective buffers against soil loss and stream sedimentation. It is noteworthy that the research was affected by the Covid-19 pandemic, which caused a time gap between the experiment and the dissertation defense, in addition to restricting the experimental period, which did not cover a complete climatological year. Despite these limitations, the findings reinforce the relevance of integrating field experimentation and spatial modeling, highlighting the importance of conservationist management in small watershed planning. It is concluded that this study expands scientific knowledge about erosion in the Pampa biome and provides technical and scientific support for soil and water conservation, contributing to the development of public policies aimed at the sustainability of natural resources.