GIS-and-QuickBird-Based Quantitative Assessment of Soil Erosion in Small Watershed.

Soil and water loss undermines gravely the sustainable development of the region.Based on the technology of GIS and QuickBird remote-sensing image,volume of the soil erosion in the watershed of Qingshuigou was evaluated,using the revised universal soil loss equation(RUSLE).Relationships of soil erosion with land use and land slope gradient were analyzed by means of spatial overlay of GRID.On such a basis,effective countermeasures for controlling the soil erosion were discussed.Results show that the annual average volume of soil erosion in Qingshuigou watershed reached 75.02(t·hm~(-2)·a~(-1)),which is in the range of intensive erosion.A soil erosion intensity map was thus obtained based on classification of soil erosion intensity,showing about 28% of the watershed suffers serious soil erosion,with sediment being higher than 16 780(t·a~(-1)) and contributed 64.5% to the watershed′s.A significantly positive relationship of soil erosion with slope gradient was observed.Soil erosion varied sharply with type of land use in a decreasing order of unusable landconstruction landcultivated slope landgarden fieldgrass landforest land.Grain for Green is one of the major strategies to reduce soil erosion and soil and water loss.