Research On Characteristics Of Ecological Threat And Ecological Restoration Of Caotang River Basin In The Three Gorges Reservoir Area

Soil erosion is a very typical process of soil degradation, is also an extremelycomplicated society· Economy· ecological phenomenon, known as the world’s topeco-environmental problems. It’s not only the destruction of land resources, restrictingplay of land productivity, but also caused deterioration of the ecological environment,and also a serious threat to economic and social development, food security and humanenvironment. Owing to this, located in the hinterland areas of the Three Gorgesreservoir area of the Daning River and the Meixi River small basin as the object of study,with the comprehensive application ArcMap9.3, ERDAS9.2, Arcview3.3softwareand the landscape ecology relevant theory, The system analysis research area1988~2010year3issue of Soil Erosions and the environment background factor spaceand time dynamic change, the pattern characteristic, and pointed out that the two smallbasin in different environmental background the risks of erosion and the stable region.Finally proposed the prevention government soil erosion countermeasure, for theresearch area soil erosion effective, the pointed government has provided the scientificbasis.The main contents and conclusions of this paper are as follows:(1) This article by3S technology as a basic means, using TM remote sensingimages, access to relevant background data from the basin DEM map, finally for fieldreconnaissance and so on method to carries on the verification, realization of the daningRiver, river basin soil erosion dynamic monitoring, ensuring research of various factorsand Soil Erosion quantitative analysis of data accuracy and reliability.(2) By3periods on the Daning River and the Meixi River basin soil erosionmonitoring analysis,1988~1999year the two basin soil erosion condition has theaggravation tendency,1999~2010year soil erosion condition obvious change for the better, But the two basin soil ersion varies greatly.(3) By analyzing the environmental background factors, In the research time theDaning River basin moderate above soil erosion mainly occurs in the500~1500melevation belt, greater than the25°slope belt, Triassic and Permian strata, Meixi Riverbasin moderate above soil erosion mainly occurs in the500~1200m elevation belt, the25°to35°and the15°to20°slope belt, Triassic and Jurassic strata, the two basins arethe largest cultivated land, followed as sparse (irrigation) woodland.(4)1988~2010year Daning River, Mei Xihe basin Soil Erosion Risk Index (R) inthe different elevation, slope, geological stratum, land utilization type displays thedifferent change characteristic, Generally, Daning River basin has experienced slightlyincrease(1988~1999year)-obviously decline(1999~2010year) the change process,Meixi River basin has experienced slightly decline(1988~1999year)-obviouslydecline(1999~2010year) the change process.(5) Varying degrees of erosion types in accordance with the Mosaic structure of thecomplex sort of Daning River basin,1988year followed by: slight, minimal, moderate,intense, very intense and sever,1999year followed by: slight, moderate, minimal,intense, very intense and sever,2010followed by: minimal, slight, moderate, intense,very intense and sever. Fdsort of Meixi river basin in1988and1999year the same,followed by: slight, moderate, minimal, intense, very intense and sever,2010yearfollowed by: slight, minimal, moderate, intense, very intense and sever.(6)1988~2010year the types of soil erosion landscape of Stability Index are bigchanges in Daning River basin, In particular, minimal, moderate, in2010, the higher thedegree of soil erosion, the lower the degree of stability of soil erosion spatial structure.In1988~2010, the Meixi rive basin various soil erosion landscape type of undulatoryproperty change is bigger than the Daning river basin.