Integrated Geographical Information System(GIS) with Universal Soil Loss Equation(USLE)

soil loss was predicted and risk areas of soil erosion were identified in Jiulong river watershed. Reasonable methods were adopted to obtain R

LS

K

C

P factors value. Results showed annual average soil erosion amount was 2 730. 3 t/ km~2 and it was in the category of middle degree erosion. The serious eroded area(sediment yield is higher than 5 000 t/km~2) only occupied 14. 28% of area

but contributed 41. 74 % of sediments in the watershed

while no or slightly eroded area(sediment yield is lower than 5 000 t/km~2) was 85. 72% of area

but contributed 58. 26% of sediments. The annual average soil erosion was higher in Chuanchang river

Huashan river

and Yanshi river sub- watersheds. The annual average soil erosion was lower in Longhai and Punan segment in North river sub-water- sheds.