The Influence of Soil and Vegetation on Hydrological Modeling in a Sub-Basin of the Araguaia River in the Brazilian Cerrado

Abstract

This study analysis the impact of soil hydraulic parameters and canopy storage on hydrological modeling in a sub-basin of Araguaia River, Brazilian Cerrado, using the MOHID Land model. Parameters analyzed included vertical saturated hydraulic conductivity (Ks), saturated water content (Θs), residual water content (Θr), and canopy storage were analyzed for their effects on river discharge. The sensitivity analysis showed that changes in Θs had a greater impact on reducing discharge than Θr, although both parameters had limited effects. Higher Ks values effectively lowered discharge peaks by enhancing soil infiltration but showed variability over time. Canopy storage was the most significant parameter, with higher values reducing peak discharge rates by intercepting and evaporating rainfall, minimizing surface runoff, achieving the best model performance. In summary, a detailed parametrization of these parameters is crucial for improving the accuracy of hydrological models.