Modelling runoff processes in a small agricultural watershed using a fully-distributed hydrological model
A fully-distributed hydrological model was applied to simulate runoff processes at an hourly time step from 2005 to 2009 in the Steppler sub-watershed of the South Tobacco Creek watershed in southern Manitoba. After incorporating snow redistribution process, the model performance, particularly the water balance for the outlet and inside stations was considerably improved. The spatial distribution of surface runoff varied over seasons where more surface runoff was generated from forest and stream valleys in spring, and from clay loam soil in summer. The spatial distribution of soil moisture was mainly determined by the soil texture. Additionally, this model was applied to assess hydrological impacts of land use changes. The forestland scenario reduced more surface runoff which was almost uniformly distributed and led to less peak flow than the grassland scenario, compared to the base scenario. A considerable difference in the spatial distribution of soil moisture was found in three scenarios.