Morphological Characteristics And Influencing Factors Of Gully In Loess Hilly And Gully Region

Soil erosion is one of the most important ecological problems in the world.Once it occurs,the soil fertility will be reduced,which will lead to land degradation and agricultural production,deterioration of the local ecological environment.Soil erosion is one of the main problems of soil erosion,so it is necessary to study the gully.In this paper,we analyze the morphological characteristics of the gully in Wuqi.In the field investigation,we selected 51 gullies,We study the relationship between the trench morphology and the environmental factors.Two methods are used to carry out the field measurement,and the volume of the two is calculated.The error analysis of the two groups is carried out.We construct the BP neural network model,And the cross-sectional shape of the cut groove is judged by a quantitative method.(1)The length of the gully is mainly concentrated in the range of 2.07 ~ 15 m,the width is concentrated in the range of 2 ~ 10 m,the depth of the gully is distributed in the range of 1 ~ 5m.In the same section of the same gully,upper width> middle width> bottom width.In the different parts of the gully,in the bottom of the gully,the ratio of width to depth is the largest,and the ratio of upper width and bottom width is the largest.The ratio of width to depth and the growth rate of cross-sectional area are gradually increasing,and the ratio of bottom width and top width is gradually reduced.(2)There is a significant positive correlation between volume and length,width,depth,so is to length and width,length and depth.The ratio of width to depth and depth has a particularly significant negative correlation.(3)As the slope increases,the average length and width increase,the depth change is not significant.The mean gully length,average gully width and average gully depth of the gully in the slope are shaded > semi-shady > semi-sunny> sunny.The vegetation coverage at the bottom of the gully is mainly between 30% and 50%,and there is a significant difference between the active gully and the less active gully in vegetation coverage.The elevation is increasing,the average length of the gully,the average width first decreases and then increases the final decrease,the average depth is getting smaller and the depth of the overall change is small.(4)By constructing the BP neural network model,the quantitative analysis method is used to determine the shape of the cross section,and the method of judging the shape of the cross section is transformed from qualitative analysis to quantitative analysis.