Effects of land use types on soil fertility in Luguhu watershed

By the method of soil sampling and laboratory analysis,effects of different land use types on soil fertility have been discussed in this paper.Three main types of land use including farmland,grassland and forestland in Luguhu watershed,Yunnan,China,have been selected,and soil physical and chemical propeties have been studied.The results are as follows:(1) The different land use types have significant impacts on soil fertility.Soil water content,total N,hydrolysable N,available P and available K are relatively higer in farmland.(2) Organic matter is higer in forestland,while total P and total K are higer in grassland.(3) Soil total N has significant positive correlation with soil sand(0.02mm),while soil total K has significant negative correlation with soil silt(0.002-0.020mm) at 95% level.