Remote Sensing Monitoring And Environment Analysis Of Soil Erosion In The Three Gorges Reservoir Area

Soil erosion has become the worldwide serious environment problem, threatening the human sustainable development. Soil erosion is also one of the eco-environmental issues that cover the largest areas and have the most harmful impact in China. In Three Gorges Reservoir areas, soil erosion is one of the great pollution sources to eco-environment Thus, it is necessary to monitor and analyze the condition and dynamic change of soil erosion. Comparing with other methods of monitoring and analyzing soil erosion, remote sensing method has the characteristics that is multi-types, multi-platforms, multi-temporal and multi-bands, and has advantages of rich information, short time period, reflecting updating condition and macro-scope information. It is undoubtedly one of the fast and effective techniques.On the basis of soil erosion researches and remote sensing monitoring methods home and abroad, We selected Three Gorges Reservoir areas as the study area, and carry out thorough discuss and deep research into the computing techniques and methods of soil erosion impact factors utilizing TM images, SPOT4 images (Acquisition time is respectively Apr., 1992 and Sep., 2002) and other subsidiary data. we have carried on the pretreatment to the remote sensing data; And unifies auxiliary material, For instance, the terrain, the climate, the soil. we used the spatial information extraction technology and the method has withdrawn the each influence factor data of soil erosion; Using the adjusted soil erosion model calculates and counts in soil erosion quantity and the intensity distribution in 1992 and 2002, and analyze the dynamic change's rules of soil erosion in Three Gorges Reservoir areas. And based on this, according to the soil erosion influence factor's change, we have made the analysis to soil erosion's environment factor, and proposed the soil erosion prevention method and the measure.The main researches and Conclusions in this paper are as follows:(1) In this research, We applied successfully remote sensing and the geography information technology, and get the soil erosion's dynamic change monitoring result of the Three Gorges Reservoir areas, This research may provide the technical support and the reference for the next basin soil erosion research, and provides the essential data for the basin forestry plan and the conservation of water and soil plan.(2) Refer to soil erosion model of Universal Soil Loss Equation (USLE),using the Three Gorges Project ecology and the environmental monitoring information management center's soil erosion experiment observation data, we calculated the soil erosion model adjustment parameter, thus we established the soil erosion quota remote sensing monitor adjustment model for suited the Three Gorges Reservoir areas.(3)In 1992 and 2002 soil erosion dynamic monitoring result of In Three Gorges Reservoir areas indicated: because it influence of various factors, in 2002 is compared in 1992 the soil erosion intensity change the overall tendency is the aggravating.(4) Through the soil erosion result and the soil erosion various environment factor's analysis,we have obtained them and the soil erosion relevance, the slope is bigger, the soil erosion is more serious; The rainfall amount is bigger, the soil erosion is more serious; soil erosion intensity enlarges in turn for the yellow soil, purple ochre, the yellow brown earth, the cultivated fluviogenic soil; The vegetation degree of coverage is smaller, the soil erosion is more serious; The land utilization type different will also be affecting the soil erosion degree occurrence, the forest land, and the shrub land soil erosion is micro, paddy field, terraced field, field is slight, stocked land is moderate, lawn is the intensity, the bare land is the pole strength, the arid land (slope farming) displays for the soil erosion is fierce.(5)Afer in analysis soil erosion monitoring result and soil erosion environment. We have proposed soil erosion prevention strategy for in Three Gorges Reservoir areas:it is Through biological control measures and the reduced slope face amount of runoff and so on afforestation, Returning farmland to forest, slows down the runoff speed, sharpens the soil infiltration capacity and the slope face anti-flushes ability, and raises mechanical control measures as far as possible and so on basis of erosion. Might carry on the soil erosion for the Control section the prevention to provide the auxiliary decision-making and the support.