The Soil Erosion Dynamical Changes Analysis In Hunyuan County Based On Remote Sensing And GIS

With the development of social economic, land resources has been sufferd unreasonable use in a long term by human beens, it has caused global degradation of soil resources, destruction of vegetation, and soil erosion is becoming increasingly serious. Soil erosion has become a global environmental problem and it also becomes a serious threat to human survival and development. Recently, many researches focused on quantitative and qualitative research about soil erosion, but researching soil erosion in a dynamic way is very seldom. In this study, we based on soil erosion theories and relying on remote sensing and GIS technology, to study soil erosion and dynamic changes in Hunyuan County.Hunyuan County is located in the edge of the Loess Plateau; it has complex landform types, ravines, fragmented, and sparse vegetation, so its soil erosion is very serious. According to Classification and Gradational Standard of Soil Erosion (SL190-2007) which approved by the Ministry of Water Resources, basing on the data of vegetation coverage, land use, slope and climate rainfall from the interpretation of remote sensing, combining with spatial analysis functions of ArcGIS, we achieved raster map about soil erosion quantity. The soil erosion intensity was graded according to Classification and Gradational Standard of Soil Erosion (SL190-2007), generated the soil erosion classification map of Hunyuan County. We also depthly studied soil erosion spatial distribution characteristics of soil erosion and the relationship between impact factors and soil erosion. The main contents include:(1) Firstly, we expounded facing the problem of soil erosion in the study area, as well as conventional technical limitations for research soil erosion. Because of remote sensing and GIS technology have their own technical characteristics, they have unmatched advantages that other methods do not have.(2) Applied the remote sensing and GIS technology, we get the vegetation coverage of study area; Combined with land-use data, topography, slope, soil texture, natural influencing factors, we obtain the land use map; According to Classification and Gradational Standard of Soil Erosion (SL190-2007) and basing on the data of vegetation coverage, land use, slope, we achieved soil erosion intensity classification and grading information of Hunyuan County.(3) By remote sensing and GIS technology, and based on1989,2001and2009three periods of soil erosion, we analysised intensity dynamic temporal and spatial variation of the quantitative of Hunyuan County. Through analysis soil erosion, temporal and spatial variation of soil erosion area, we summarized change rate of soil erosion intensity. The results show that the mountainous areas of the study area and the hilly area are key areas of Water Conservation, and moderate erosion and slight erosion is mainly, followed by slightly eroded soil erosion area.With the increase of soil erosion intensity the area quickly reduced.Finally, according to the soil erosion of Hunyuan County we summarized several suggestions of ecological restoration measures. These ecological restoration measures can provide reference and basis for better planning and management of of Hunyuan County soil erosion, to further improve the ecological environment and sustainable social and economic development.