The development of land use planning scenarios based on land suitability and its influences on eco-hydrological responses in the upstream of the Huaihe River basin

The SWAT model with daily time step was set up for the studied area. It simulated reasonably the relationship between rainfall and runoff with the Nash-Sutcliffe efficiency (NSE) values of 0.72 and 0.66 for the calibration and the validation periods. Relative changes of eco-hydrological components simulated by the validated SWAT model were analyzed both temporally and spatially. The simulation results counted at multiple temporal scales showed that both short-term and long-term land use planning operations reduced the maximum runoff and total water yield as well as the total sediment loads, meanwhile, increased the evapotranspiration. For runoff components, the decreasing surface runoff and the increasing groundwater were much more significant than the increasing lateral flow. Sub-basin analyses revealed that the simulated changes in eco-hydrological responses varied spatially, whereas the decreases in total water yield and the surface runoff and the increase in evapotranspiration were closely related to the percentages of de-farming in sub-basins. Overall the eco-hydrological responses to long-term land use planning were more profound than that to short-term land use planning. This study provides a synthetic suitability evaluation method for creating land use planning scenario, which overcomes the shortcoming of traditional way of assigning land use scenario that being lack of objectivity.