To explore the characteristics of soil and water loss in the Karst region

we analyzed the spatial statistic features and soil erosion characteristics of blocks. According to the First National Water Census

field surveys were carried out using blocks as the minimum survey units. A block is an area in which land use

soil and water conservation measures and coverage are identical. Soil erosion modulus was calculated using CSLE (Chinese Soil Loss Equation). The results showed that farmland and forest were dominated in the Karst region

accounting for 86.2% of the total area. Because of cracked terrain and steep slopes

the landscape showed fragmentation characteristics. The average area

slope length

slope gradient of blocks were 3.45 hm2

45.3 m

and 21.7°

respectively. Analysis of the erosion modulus showed that 68.6% of farmland blocks had steep gradients and accounted for 65.6% of the total sediment yield. About 50% of farmland suffered severe erosion. The effects of slope gradient on soil erosion were significantly greater than that of slope length. Engineering measures reduced soil erosion by 75%. With the increase of slope gradient

the efficiency of engineering measures in reducing soil erosion decreased and became smaller than that of the forest and grassland. The most serious soil erosion occurred in southwest of Guizhou Province

and the degree of soil erosion decreased from west to east. When planning for regional soil and water conservation

the most seriously eroded area should be given the primary consideration

and reducing cultivation on steep slopes and returning farmland to forest should become the first choice.