关键词: 水土流失, 坡地退化, 坡地整治, 立体开发, 华南

Abstract: According to the samples from Wuhua County,Guangdong province,degraded slope on lateritic red earth in South China has the following properties.1.Pedogenic horizons are denuded.Litter horizon(A0) has disappeared; organic horizon(A)is non-clear,replaced by the transitional horizon of (AB),even (A) horizon is fully eroded,illuvial horizon (B) is revealed on the ground.2.Soil becomes sandy.Slope on arenaceous shale sandifies slightly,soil texture is still nainly "non-stony heavy loam" (> 3 mm stony content is less than 0.5%,<0.01mm physical clay 45-60%),slope on weathered granite sandifies seriously,soil texture has generally degraded to "heavy-stony medium loam" (stony> 10%,physical clay 30-45%).3.Soil chemical characteristic deteriorates.In our view,slope on lateri-tic red earth in South China starts to degrade once the content of soil organic matter falls below 3%.Soil and water loss from inappropriate land use system including farming,on steep slope,plowing up and down hills,monouculture farming,and over felling forests is the major cause of degraded slope in mountains of South China.The degraded slope in Wuhua County has been managed and developed according to different degraded degrees.