Research On The Application Of Different Hydrological Models In Semi-arid And Semi- Humid Areas

In recent years, China’s climate change anomalies and flood and drought disasters occurred frequently. Timely and accurate flood forecasting can provide a scientific basis for making the right decisions, which has achieved great economic and social benefits in the previous fights against the flood. Due to the special natural and geographical environment, semi-arid and semi-humid area has many characteristics which are different from the humid area. Therefore, the flood forecasting method in the region has been a hot and difficult point. This thesis takes many river sites and reservoir sites of Hebei province and Ningxia Province as an example and adopts the Hebei storm flood model, MSKLOSS model and Ningxia small basin runoff forecast model to simulate the flood process.The main research contents and results are as follows:(1) The basin runoff forecast:This thesis introduces the calculation method and runoff etc. of Hebei storm flood model. It selects the typical flood process of the Hutuo River since 1953 as the research object and established flood forecasting schemes of Xiaojiao station, Gangnan Reservoir station and Huangbizhuang Reservoir station to carry out flood forecast. The results show that the Hebei storm flood model has good applicability in the basin. But Different order of magnitude of the flood need to establish forecasting scheme of different parameters to improve the prediction accuracy. Due to changes in watershed underlying surface conditions is intense, parameter WM and confluence parameters need to be modified in the actual forecast process with experience.(2) The river runoff forecast:This thesis introduces the Muskingum method theory, Horton infiltration theory and innovatively combines the two kinds of theories to form MSKLOSS. It selects the Zhanghe River as the research object, uses the two models to simulates the floods since 1982 and automatic calibration parameters. Then it analyzed the accuracy and applicability of the model before and after improvement. As a result, the simulation accuracy of MSKLOSS is significantly higher than the Muskingum method, especially in the aspect of flood volume, and can be promoted and applied in semi-arid and semi-humid area.(3) Small rivers without data runoff forecast:According to the Ningxia Hui Autonomous Region storm flood atlas of the flood design method, the author developed the Ningxia small basin runoff forecast model-SBRF_NX which is integrated into China’s flood forecasting system. This thesis detailed introduces principle and operation steps and analyzes the flood forecast simulation and model parameters values according Jinghe River-a tributary of the Yellow River Basin. It turned out that the results of the peak flow forecast are more accurately, which is consistent with the attention focus on peak flow. The model is reliable and feasible, and can be used for flood forecasting in Ningxia area of small rivers without data.