Studies on the Coupling Relationship between Soil Erosion and Land Use in the Upper Reaches of Minjiang River

Coupling relationship between soil erosion intensity and land use types in the upper reaches of Minjiang River was studied by using the data of land use and soil erosion in 2005 with the support of GIS technology.Close relationship was found between soil erosion and land use,and the soil erosion intensity and spatial distribution were directly influenced by land use.Forests and grassland were the main land use types,bare rock and construction land area accounted for only 0.11%.Different land use patterns had different soil erosion intensity indices,and in the order of dry landgrass land with low coverage other forest landmoderate coverage grasswater areahigh coverage grassconstruction landopen forest landshrub land forest landpaddy fieldbare rock.Slight water erosion was the main type of soil erosion,accounting for 35.43%,and mainly occurring in forest land and shrub land,accounting for 14.24% and 11.70% of the study area respectively.Low and moderate intensive water erosion occurred in the grass land with moderate coverage.With the increase of the soil erosion intensity,erosion area of dry land gradually increased,and far greater than paddy fields.Frozen erosion accounted for 26.96% and mainly occurred in the grass land with moderate coverage,accounting for 20.89%.Therefore,reasonable land use type and optimized land-use pattern are essential for the control of soil erosion,protection of land resources and improvement land use efficiency,as well as for the promotion of socio-economic development of the basin.