Construction And Application Of Hydrology Model Of Typical Middle Reaches Of Yellow River

Under the influence of climate change and human activities,the underlying surface of the Yellow River Basin is constantly changing,which in turn leads to a more complex mechanism of production and confluence.This paper is under the support of the “Thirteenth Five-Year Plan” National Science and Technology Support Plan“Mechanism and Trends of Water and Sediment Changes in the Yellow River Basin”.Topic 2 "Mechanisms and Simulations of Multi-Scale Flooding and Sediment Conveying in the Yellow River Basin" 3 "Underlying Surface Changes The mechanism of production and sinking and production and sediment transport are the foundations of the study.Based on the analysis of the production and convergence model in the middle reaches of the Yellow River,a distributed hydrological model based on different production and confluence modules was constructed to conduct in-depth study on the flood process simulation under the changing surface conditions.A distributed hydrological model was used to simulate the flood process using different production and sink modules in a typical catchment of the middle reaches of the Yellow River,Jingle Station Control Basin in the upper reaches of the Weihe River and the Chabagou River Basin,the simulation results were evaluated and verified to validate the applicability of the model.The results of this study can not only provide a reference for the flood forecast in typical catchment of the middle reaches of the Yellow River,but also enrich the application of the distributed hydrological model in the semi-arid and semi-humid regions.The main contents and results of the study are as follows:(1)Read relevant research results concerning changes in underlying surface conditions caused by climate change and human activities in the middle reaches of the Yellow River,and analyze the patterns of runoff production and confluence in the middle Yellow River under changing underlying surface.The analysis results indicate that the ultra-permeability flow pattern dominates the middle-river runoff of the Yellow River.With the continuous change of underlying surface,the flow patterns of some watersheds in the middle reaches of the Yellow River will change,and the local flow will become fills –excess infiltration compatible mode.(2)Considering the condition changes of the underlying surface in the middle reaches of the Yellow River,a distributed hydrological model based on the modular idea is constructed.A distributed hydrological model was constructed to consider two modes of flow generation,namely,the ultra-osmotic flow and the reservoir-ultra-osmotic mixed flow generation in the flow generation module,in the convergence module,the non-dimensional unit line and equi-flow time-line method with wide applicability are used to calculate the slope convergence.The distributed hydrological model to be constructed is applied in a typical catchment in the middle reaches of the Yellow River,and its simulation accuracy is evaluated and analyzed to verify its applicability.(3)The application of the constructed hydrological model to the control of the watershed at the Jingle hydrological station in the upper reaches of the Jinghe River indicates that the model was used to simulate the ultra-osmotic flow model in the basin from 1980 to 1998,the results were satisfactory and reached the level B forecast.The mixed production flow module is relatively poor at this stage.In the simulation forecast from 1999 to 2014,the mixed flow generation module was used.The simulation result was ideal and it was the second-grade forecast accuracy.In the simulation forecast from 1999 to 2014,the mixed flow generation module was used.The simulation result was ideal and it was the second-grade forecast accuracy.It shows that the Jingle Station controls the change of the conditions of the underlying surface,and the mode of production flow has undergone certain changes.(4)The model was applied in the Chabagou watershed.Except for the flood simulation result with the flood number of 060,730,the results of other flood simulations results were relatively satisfactory.The reason for this is not necessarily that the hydrological model constructed in this study is not applicable to this area,due to the limited data collected during the process of flood field selection in this basin,the number of selectable floods is less,and the subjective influence of the selection process is greater.Therefore,the application of the model in the watershed remains to be further investigated.