The Evaluation Of Potential Soil Erosion Risk Based On GlS Technology

Soil erosion people are facing now is one of the most general and persistenceEcological geological disasters and becoming not only china’s environment problembut also the whole world. In recent years, the study of soil denudation manlyconcentrate on the soil erosion amount. truly the soil erosion amount can reflect theamount of soil loss in eroded area, but it can not reveal the danger level of theeroded area. though in some places, soil erosion amount is not that much, theconsequence are far more serious and that’s why we need the potential hazardousassessment of soil erosion. we can analyze the evolutional mechanism of soil erosion,forecast the trend of soil erosion in eroded area and put forward thecountermeasures by studying the potential hazardous assessment of soil denudation.we took the Talatan Gonghe basin, located in the northeast of Qinghai provincefor the studying example, estimating its potential hazardous assessment. we use themethod of cs-137isotope and the method of anti-erosion time to estimate thesoil erosion amount and the anti-erosion time. we classify the danger level by usingthe standard of potential hazards on soil denudation, besides we add gis in it duringthe classification. With the help of land use map and DEM map, we get the spatialvariation of soil denudation in study area. The result shows:According to the soilerosionmodulus calculated by the content of cs-137in the example soil and thenational, we can know that most of study area belongs to the micro soil erosion andslight erosion which takes99.97%of the total study area；the potential danger level ofsoil denudation in study area consist of five levels: no hazard，slim hazard, ratherhazard, huge hazard, destructive hazard. From the perspective of anti-erosion time,the range of anti-erosion time manly distribute from100-year to1000-year, and themost widespread hazard level is slim hazard which covers an area of1692.98Km2,61.64of the total area of Talatan. From the prospective of spatial analysis potentialhazard level of soil denudation. the hazard level are related to the slope gradient,aspect, plant coverage, land utilization type.the potential danger level of soildenudation increases with the increase of slope gradient, the potential danger level of soil denudation in the sunny slope is more serious than the northern slope, smaller thevegetation coverage is, the greater the potential risk of soil erosion will be and humanactivities could acc accelerate the speeding rate of soil denudation.