Study On The Change Of Land Use Structure And Its Effect On Soil Erosion In Ningxiang County

Soil erosion is a global problem.Our country is one of the areas of serious soil and water loss in the world.With the rapid economic development of our country, water loss and soil er osion situation is becoming more and more serious. Water and soil is the founding of a country that is the human survival basic material. Therefore, the study of soil and water is loss more and more. This article selects Ningxiang County as the research object, through the study on regional landscape pattern of landuse and soil erosion intensity analysis, and find out the connection between them.For our country economy developed urban areas of rational utilization of land and provides the theory basis for prevention and control of soil and water loss.The results are as follows:(1)The forestland (evergreen coniferous evergreen broad-leaved, shrub forestland) area is the largest in the research area,showing planar distribution. The second is a paddy field, along the forest edge showing linearly distributed. The proportion of other land type area is not high,the rest of the class presents basic punctuated distribution.(2)Paddy and up land area of the rate of change within the study area is not high. The area of forest changed is not big. But the grassland and water area loss is bigger, from 1986 to 2005 reduced 4.842km2 and 10.282km2, grass land area decrement of 48.98% and 29.09% respectively.(3)The no soil erosion area in the region doesnot change in nine years(from 1986 to 1995, mild loss of area decreased 295.424 km2, moderate loss, loss of strength, a very dramatic loss of strength loss and increase the area of distribution 5.52%, 3.78%,0.84% and 0.02%;this seven-year period from 1995 to 2002 without the loss of area decreased 16.21%, substantially all of these in to a mildloss, moderate, and little change in strength drain area, very strength and dramatic changes in the larger area of the rate of change wastage; this three-year period 2002-2005,the loss of area change, and trends 1986-1995 is basically the same, without the loss of an area of fundamental change, reduce mild loss of area, increasing the area of the rest of the loss, moderate erosion and the loss of an area of extreme strength highest rate of increase, respectively, reached 112.44% and 60.29%.(4)In 1986-1995-2002-2005 years, the number of patches (NP) micro gradual increase in the degree of loss, indicating the degree of fragmentation loss in micro gradual increase in the number of plaques decreased mild loss, moderate loss,strength loss,extreme strength loss and severe loss of variation of the number of patches is not obvious; maximum number (LPI) plaques in 1986-2005 the largest loss among all the micro level,at the 1986 annual minimum to maximum 80.11146,2002 is 63.3997; between 1986-2005,patch shape index are micro degrees drain> mild loss of>mode rate loss> strength loss> extreme strength loss> severe loss; change its variation is consistent with the patch shape index trend.(5)From the landscape point of view,the number of patches of soil erosion from in 1002 to 3211 in1986-2005; patch density of 0.3525 from 1986 increased to 1.4763;largest patch index and contagion index in to a decreasing trend, the spread and tied index, diversity index and evenness index increase.