APPLICATION OF AHP (ANALYTIC HIERARCHY PROCESS) FOR DETERMINATION THE AFFECTING MAIN FACTORS IN SOIL EROSION AT SONG BE BASIN

Soil erosion is a global environmental problem. The affecting main factors for soil erosion processes are different due to the specific areas. The calculated results of soil erosion, by Ha Quang Hai and Tran Tuan Tu, demonstrated that Song Be basin is eroded very huge, about 321 tons/ha/year. The article is based on factors proposed by R.P.C Morgan in 2005, using the analytic hierarchy process AHP (Thomas L. Saaty, 1970) to determine the weights for these factors. Since then, the article concluded main factors affecting soil erosion at Song Be basin. Research results showed that the Terrain factor has the largest weight (0.30), followed by two factors: Plant cover (0.29) and Rain (0.28). The article also identified four main factors impacting on the soil erosion at Song Be basin, including: slope, land cover ratio, intensity of rainfall and slope length. These results will be the basis for subsequent studies to adjust USLE model more applicably for erosion characteristics in the researched area.