| The fragile ecological environment, poor agricultural production condition, low socio-economic level of Three Gorges reservoir area in Hubei is one of the strong soil erosion in the Yangtze River upper reaches. Yichang under the jurisdiction of counties (districts) covers more than 30%. Unreasonable or over-exploitation of land resources made soil erosion severely.After the construction of Three gorges project, large-scale of immigrating made the contradictions of land shortage and environmental carrying more prominently, and soil erosion further severely.This paper is based on Soil and water conservation monitoring center of Hubei province scientific research projects "Wangjiaqiao watershed database construction and water and soil conservation system evaluation", Three Gorges reservoir area Hubei section for research object, through collecting research area and the basic data of soil and water conservation, using the geographic information system technology to build the Three Gorges reservoir area in Hubei soil and water conservation database, analysing the study area, soil erosion factors, the dynamic change of soil erosion intensity and soil erosion risk under the condition of different soil erosion background to understand research area's law of soil erosion.This paper mainly research results are as follows:(1) To collect and arrange Hubei paragraph Three Gorges reservoir with soil and water conservation related basic data,including DEM data, remote sensing image data, NDVI data, soil data, runoff plot data and meteorological observation data,and establish the Hubei area Soil and Water Conservation database.(2) Analysis the change rule of Hubei period Three Gorges impact factors of soil erosion. Results show that the study area more than 1000m land area at an altitude of most, gentle slope, slope and steep slope land distribution the most widely used; Research area rainfall has the little trend of decreasing,and the rainfall is gradually decrease from south to north; Study area NDVI value per unit area for many years is 0.587,showing a rising trend,and low vegetation coverage mainly appears in the Yangtze river near the river; From 1999 to 2007, stumpage area increases most,while upland area decreases least, the land use structure changes presents woodland, paddy fields, construction land and water area increasing, open woodland and upland area presenting descending trend on the whole.(3) Use RUSLE model to calculate two times of the soil erosion intensity of three gorges Hubei section. Results show that research area from 1999 to 2007 micro degrees erosion, extremely strength erosion area ratio fell, mild erosion, moderate erosion, strength erosion and intense erosion area ratio has certain increase,and erosion transfers high-grade; Serious soil erosion is mainly distributed in the mountain areas of the canyon high valley area; Study area soil erosion is mainly produced by intensity erosion and extreme erosion, In 2007 the both erosion is the total's 49.45%.(4) Using corrosion life method to calculate Three Gorges Hubei section's fixed number of year soil corrosion, and the soil erosion potential risks were classified. Results show that the soil erosion in the study area is with misses type and potential risks are mainly type light risks. The whole area studied soil erosion potential risk index for SEPDI is 1.40, each county SEPDI value is less than 2,showing that the risk of soil erosion in whole study area is not high. And analyse the backgrounds of different soil erosion potential erosion risks, believing that 200～500m elevation with the greatest degree of erosion risk is the biggest;> 35°slope with the most severe degree of erosion; northwestern slopes of the value relative to other aspect SEPDI larger degree of erosion; the soil Type, brown and dark brown in the erosion of the largest proportion of non-insurance type, soil and purple soil, lime soil erosion risk index minimum; vegetation coverage levels to 45 to 60% in the SPEPDI is the highest.
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