Study On Relationship Between Soil Erosion And Shallow Landslides In Loess Gully Region

Natural disasters happen in the loess Gully region of China, especially in the function of short term, heavy rain or storms, shallow landslide disasters take place frequently, with a large number of soil erosion phenomena. As a result of these serious disasters, the development of the local agricultural economy is greatly restricted, and even posing a threat to people’s lives and property.Based on the abundant articles by predecessor’s works, We carried out a serious of field investigation and laboratory testing after referring to lots of related literature, Additionally, a typical representative of the loess plateau region was chosen as the object of study, then the characteristic of geomorphology in the area where frequent geological disasters happened was analyzed. Based on the Topographic Information with the help of DEM method provided by1:5,000topographic map, combined with GeoWEPP model and SHALSTAB numerical simulation study on the model, the degree of soil erosion in distribution and stability of shallow landslide was forecasted respectively. In the last, the relationship between shallow landslides and soil erosion was studied as well.GeoWEPP model is a WEPP model based on secondary development of GIS software platform based on distributed model of soil erosion model; SHALTAB model is a method for quantitative assessment of the spatial and temporal of landside stability by taking steady-state model of hydrological assumption and infinite slope assumption into consideration. According to the results of the two model simulation and the field survey outcomes, most of landslides happen in the region of potential instability area; with the help of GIS spatial analysis functionality of the software, we discovered that the serious soil erosion area is also the surface unsteady area after putting the surface stability level distribution maps and soil erosion level map together.Through comparative analysis to predict the outcome, and the combination of landscape features, the following conclusions can be drawn:In the function of water and wind, soil particles may separate and move, and develop in gully region gradually, rainwater penetrates in groove, the landslide gradually formed. As the rain continues permeation, soft soil becomes easier to slip. With the increase of soil erosion, landslide falls in steady at last, which contribute to a great harm to soil erosion. Overall, the shallow landslide in the entire soil erosion process of playing a leading role in controlling the entire watershed soil erosion.