COMPARATIVE SURVEY AND ASSESSMENT ON WATER EROSION IN TYPICAL CATCHMENTS OF THE LANGCANG RIVER BASIN

Both gully erosion and surface erosion were investigated. Since the scale of these different erosion processes is different, different methods are also needed for gully erosion and surface erosion. For surface erosion, plot observations were made, but for gully erosion a survey was conducted in the 4 sub-catchments. In both cases, the factors influencing soil erosion were analysed and surface erosion susceptibility and gully erosion severity were classified. Finally the soil erosion situation in the 2 catchments was assessed using the results from both the surface erosion study and the gully erosion survey. The clear difference in erosion between the different catchments is caused by differences in gully erosion, since surface erosion is quite similar in different catchments.