Aplicação do Modelo Soil And Water Assesment Tool (Swat) na bacia hidrográfica do Ribeirão Taquaruçu.

The hydrological models are important tools to evaluate the hydrological behavior of watersheds, helping in the decision making. Thus, this study had the objective of evaluating the performance of the Soil and Water Assessment Tool (SWAT) model in the flow simulation in the Ribeirão Taquaruçu Hydrographic Basin. Flow data from two fluviometric stations were used from April 2013 to August 2015. The results of the sensitivity analysis indicated that the most influential parameters are the SOL_K (saturated hydraulic conductivity of the soil) and CN2 (curve number for the condition II). The Nash-Sutcliffe (NSE) objective functions and the determination coefficient (R2) indicated, in the calibration period, the following values: -0.05 and 0.55 (sub-basin 1); 0.51 (sub-basin 3), respectively. In the validation period, the following results were presented for NSE and R2: 0.44 and 0.54 (sub-basin 1); 0.24 and 0.29 (sub-basin 3), in that order. Considering that the object of study is responsible for a large part of the water supply of Palmas - TO and that the program was unable to simulate the minimum flows adequately, the results are considered unsatisfactory