Simulação da produção de sedimentos para bacia hidrográfica do rio Mundaú através do modelo SEDNET

Abstract

The erosive processes produce several economic and environmental losses and have been interest theme of many researches. The scientific and technologic advances and the mathematical models development have possibilitated quantify theses process, allowing to estimate the magnitude of the problem and thus be able to minimize them. In this regard, this work used the SedNet model (Sediment River Network) in river Munda´u catchment for sediment yield simulation under two different use and soil cover scenarios (forest and soil current use). For the simulation, the model employs a special watershed database, consists of geographical, pedological, hydrological and climate information. The work consists in three steps: (1) Acquisition of hydrological data; (2) Determination and mapping of the factors of Universal Soil Loss Equation and (3) Simulation of sediment yield. Since the input data have been correctly prepared, they were manipulated in the model interface, into which the Digital Elevation Model (DEM), soil use and occupation map, pedological map, climatic map and stream flow of data. After that, was simulation carried of sediments suspended yield for different scenarios. Moreover, was made the sensitivity analysis of the parameters hillslope sediment delivery ratio (HSDR) and runoff coefficient (RC) in order the verify its influence in the sediment suspended total load. The results obtained showed a reduction quite significant sediment yield in the representing scenario the catchment without anthropic actions when compared to the usage scenario and current coverage of the soil of catchment. Since the results the sensitivity analysis showed that the suspended sediment load simulated by the model was sensitive to parameter variations HSDR and a few sensitive to variations of RC.