Simulation Model And Influencing Factor Analysis Of Rainfall Infiltration Runoff On Slope

Soil water infiltration is the inherent characteristics of soil,which refers to the process of water entering the soil through the ground,and is an important link in the conversion of precipitation and surface water into soil water and groundwater.The process of soil water infiltration is an important part of the hydrological cycle of the watershed,and is closely related to soil water redistribution,soil erosion,nutrient transfer with water,and agricultural non-point source pollution.Soil infiltration performance is closely related to slope soil erosion and runoff.It is the starting point for studying surface runoff and slope erosion.Studying soil infiltration performance is of great significance for understanding regional runoff and runoff issues.In order to develop and make better use of the land resources of slope farmland,to control the problem of soil erosion and the problem of ecological environment,it is necessary to study and understand the law of soil infiltration on slope farmland.In order to study the process of erosion and infiltration on slope farmland,this paper selects Chabagou watershed in Zizhou County,Yulin City,Shaanxi Province and Guanshan River Basin in Guanshan Town,Danjiangkou City,Hubei Province as the research objects,and conducts infiltration performance on slope farmland Experiments and research,with a view to drawing some conclusions on the relationship between infiltration of slope farmland and rainfall runoff.After the research in this article,several main conclusions are drawn:(1)The experimental process and results of double-loop infiltration experiments and rainfall infiltration experiments conducted in different watersheds are affected by the physical and chemical properties of the soil itself.In the same watershed,because the soil texture is relatively uniform,it is mainly because the bulk density of the soil affects the infiltration process and results.The larger the bulk density of the soil,the lower the steady infiltration rate of the infiltration process.The difference in the infiltration process between different watersheds is mainly caused by the soil texture,soil structure and organic matter content: the viscosity of the soil plays an important role in the stable infiltration rate of the double loop infiltration between the two watersheds.From the data,it can be found that the average organic matter content and the percentage of water-stable aggregates of> 0.25 mm in the two river basins are both small,and the impact on the steady permeability rate is also low.The influence of the soil viscosity in the Chabagou watershed on the steady permeability rate plays a major role.The higher the soil viscosity,the lower the soil porosity.The analysis results of double-loop infiltration are consistent.(2)The experimental process and results of double-loop infiltration experiments and rainfall infiltration experiments conducted in different watersheds are not only affected by the physical and chemical properties of the soil itself,but also by external conditions,mainly reflected in the depth of the soil layer,the initial moisture content of the soil,and the rainfall intensity And human disturbances.The depth of the soil layer mainly affects the infiltration process of the double ring,the soil layer is about thin,the lower the infiltration rate during the double ring infiltration process;the higher the initial moisture content of the soil,the lower the initial infiltration rate of the soil infiltration process;rainfall intensity The larger the value,the higher the stable infiltration rate of the soil infiltration process;and the experimental site where the slope soil was disturbed by humans before the experiment showed a higher infiltration rate.(3)By comparing the experimental results of rainfall infiltration experiment and double-ring infiltration experiment,it was found that the steady infiltration rate of rainfall infiltration was greater than that caused by double-loop infiltration.There is a linear proportional relationship between the rate and the steady infiltration rate of double-loop infiltration,and the relationship coefficient is affected by rainfall intensity,soil physical and chemical properties and slope between different watersheds.(4)During the runoff of the artificial rainfall experiment,the slope runoff rate was affected by soil bulk density,soil initial moisture content and rainfall intensity.The larger the soil bulk density,the shorter the runoff time and the higher the slope runoff rate;the higher the initial soil moisture content,the shorter the runoff time and the lower the runoff rate on the slope;the higher the rainfall intensity,the easier the surface of the soil to produce Skinning leads to shorter runoff time and higher runoff rate.(5)The Philip model,Horton model and Kostiakov model were selected to simulate the soil infiltration process in the two watersheds.After analysis,it is found that the Horton model and the Kostiakov model can simulate the soil infiltration process in the two watersheds well.The parameters in the Kostiakov model can be obtained based on the analysis of the soil physical and chemical properties and initial moisture content,so it is easier to apply.Based on the double-ring infiltration process,combined with the analysis of the numerical relationship between the double-ring infiltration and rainfall infiltration,the slope runoff infiltration runoff process is calculated and simulated,and the slope runoff runoff model can be obtained.Thecalculated slope runoff model is fitted to the actual runoff process,and a good fit is obtained,which shows the reliability of the slope runoff model.