Methodological Contribution to the Assessment of Generation and Sediment Transport in Tropical Hydrographic Systems

The efficiency and useful life of reservoirs are directly related to the production and input rates of sediments resulting from erosive processes at the edges and those resulting from the action of surface runoff in contribution areas and transported via tributary channels. Knowledge of the intensity, as well as the relationship between generation and input, allows more precise identification of critical environments, helping in the decision-making process and allowing the definition of mitigating measures. This work aims to relate the spatial variability of soil loss with the respective sediment transfer potential in two sub-basins tributary to the HPP Batalha reservoir in the Midwest region of Brazil. The methodology comprised the bivariate analysis between estimates of soil loss in areas of contribution and the Declivity-Extent Relationship along the channels. The results point to the configuration of four spatial patterns, indicating different levels of criticality in terms of sediment generation potential and transport capacity. In addition, they highlight basins with high potential and greater proximity to the reservoir, which constitute priority areas for monitoring, especially the conditions of soil cover and management, to contribute to the reduction of sediment inputs and prolong the efficiency of these structures.