Dynamic Change Analysis On Soil And Water Loss About YuJing Highway Based On RS/GIS

This paper use RS / GIS technology as primary means and 1:25 million topographic as base map to analyse the current situation of soil and water lose within the 300m'area on both side of the YuJing highway in 1996 and 2006. By the method of remote sensing digital image processing, this paper extracted the leading factors of soil and water loss, such as vegetation cover, land-use type, slope, gully density , got the slope throgth digital elevation model (DEM) which generated by the raster-to-vector contour line and gave different weights for these 4 factors according to the specific condition of study area. After the spatial analysis of GIS founding the standard for classification and gradation of soil erosion and code of technique for water conservation planning, this paper got the strength level photo of soil and water lose, and then calculated the quantity of soil and water lose along YuJing highway in 1996 and 2006 by the area of soil and water lose generated in GIS in order to analyse the dynamic change for current situation of soil and water loss.By comparing analyses of strength to soil and water lose on YuJing highway between 1996 and 2006, the result are these:1. The whole quantity along YuJing highway of soil and water lose has reduced 198415t/a, local condition of soil and water lose is improved. The area of soil and water lose in very sight loss has reduced 2.52 km2, the quantity about it has reduced 1285t/a; the area of soil and water lose in sight loss has increased 3.23 km2, the quantity about it has increased 8250t/a; the area of soil and water lose in moderate loss has increased 10.86km2, the quantity about it has increased 54450t/a; the area of soil and water lose in severe loss area has increased 8.43 km2, the quantity about it has increased 68720t/a; the area of soil and water lose in strongly severe loss area has reduced 14.84 km2, the quantity about it has reduced 226950t/a; the area of soil and water lose in violent loss has reduced 4.88 km2, the quantity about it has reduced 101600t/a.2. The facers about soil and water lose casused by YuJing highway's construction has gradually disappeard along with the curing formation of road.The environment protection measures of sand control, ecological restoration and so on, taken by construction of YuJing highway has played an active role to to improve the ecological environment and prevent the soil erosion along the highway.