Modelagem hidrossedimentológica em bacias semiáridas com diferentes fórmulas de transporte acopladas ao modelo Mosee.

Abstract

The soil erosion and sediment transport modelling is very important in the analysis of the impacts of sedimentation in rivers, reservoirs and agricultural areas in semiarid catchments. It involves the hydrologic processes, soil erosion, transport and deposition of sediments, which depends on the transport capacity by the flow. Several methods for determining the sediment transport capacity by the flow are available in the literature, but, in general, not utilized extensively, particularly in semiarid regions. Moreover, the estimates may vary according to the methods in hydrossedimentological models, which are, in general, not versatile. This study aims at investigating different methods of sediment transport capacity coupled to the model MOSEE, a Model for Soil Erosion Estimation, (Yalin; Laursen and Engelund & Hansen) that was primarily tested in the cariri semiarid region of the state of Paraiba, as well as alternatives (DuBoys; Bagnold) incorporated to the model during the present study. To conduct this investigation data of runoff and soil erosion, observed at micro basins in the Experimental Basin of Sumé (EBS) and Experimental Basin of São João do Cariri (EBSJC), were utilized for comparisons and analyses. The results showed that the investigated methodologies did adequate well to the region, with mean deviation of less than 7% in general, but the equation of Bagnold best fit the observations with mean deviation of less than 0.5%.