IWRA Proceedings

AbstractIn recent years, water resources in Haihe river basin has sharply decreased. The decrease of runoff in mountain areas is one of the most important causes. Climate change and human activities such as land use change, human and domestic water use are considered as the main cause of runoff decrease. Two typical mountainous catchments in Haihe river basin were selected as case study areas. HSPF and SWAT models were employed to simulate the runoff in this area. Good agreement between simulated and observed values through calibration and verification indicated the efficiency of the model in 1960s and early 1970s. Long-term stream flows was generated by the hydrological model to obtain the quantity of decrease in runoff driven by climate change. Moreover, runoff under dry and wet years was simulated and compared to demonstrate the dominating factors of runoff decrease. The results showed that runoff decrease from middle of 1970s was not heavily driven by climate change. The rates of impacts of climate change and human activities are 34% and 66% respectively. Effect from land use and human water use should be further clarified.