Study On Runoff Production Characteristics And Parameter Regionalization In No Data Areas Of Henan Province

Henan Province is located in the middle latitudes with special geographical location and obvious transitional climate.The topographic and geological conditions in the mountainous areas of the province are complex,and the spatial and temporal distribution of annual rainfall is uneven,which makes it very easy to occur mountain flood disaster.And most areas lack runoff observation data,which makes it difficult to carry out parameter calibration.In this paper,small watersheds of Henan Province are selected as the study basins.Firstly,the regional law of the correlation between rainfall and and runoff generation mechanism are analyzed.Then,spatio-temporal variable source mixed model is used to calibrate the parameters of flood events.And the parameters of runoff generation between watersheds are transferred to each other.Finally,the CART method is used to quantify the parameter transplantation criterion in the no data areas.The purpose of this study is to deeply understand the flood production mechanism and parameter regionalization law in Henan Province,to improve the flood control capacity of the region,and to provide reference for the study of parameter transplantation in no data areas.The contents of the study are as follows:(1)The regional laws of the main underlying surface and rainfall elements in the study watersheds are analyzed.The relationship points of rainfall and runoff in 19 study watersheds of Henan Province are drawn.This paper analyzes the regional law of rainfall runoff in the study watersheds.On this basis,the runoff generation mechanism of the watersheds is studied qualitatively combined with the underlying surface and rainfall characteristics.(2)The selected flood events are simulated by using the spatio-temporal variable source mixed model,and the applicable effect of the model in Henan Province is evaluated.This paper analyzes the variation trend and regional law of sensitivity degree of infiltration excess runoff and saturation excess runoff parameters by sobol sensitivity analysis method.The runoff production parameters of the study watersheds are transferred to each other,and the training samples are obtained.(3)The uncorrelated factors are obtained by principal component analysis of attribute factors,and the CART model is constructed by using the training samples of principal component factors and parameter transplantation as input data,and then the rules of parameter migration are determined.This paper establishes the parameter transplantation standard for each watershed by using the missing one method.The suitable reference watersheds are selected,and the CART method is verified.This paper compares and estimates the transplantation effect of CART,distance approach method and attribute proximity method.Finally,this paper summarizes the research results,puts forward the shortcomings of thisstudy,and puts forward some prospects and suggestions for the follow-up research.