Evaluation of Hydrological Responses to Land Use Change at Large Scale

Responses of hydrologic process to human induced land use changes, which have affected a wide portion of China since last century, were evaluated with a coupled land surface-hydrology model. The main land use changes were assessed by the International Satellite Land Surface Climatology Project (ISLSCP) historic (1970) and potential land use types in the Huaihe River basin. The variations of flood peaks due to extensive human activities have been investigated by simulating hydrologic processes at a 10 km grid scale for the two land use scenarios forced by the same meteorological data, initial conditions and other model parameters. Results indicate that the sensitivity of the evapotranspiration, soil moisture and surface runoff to land use changes is remarkable, and demonstrates that present deforestation aggravates local flood risks. Forest planting is promoted to decrease flood damage and to protect the ecological environment.