Soil Organic Carbon and Variation With Land Use in a Fluvo-Aquic Soils From Northern Anhui

The content and section distributions of total organic carbon(TOC),dissolved organic carbon(DOC) and microbial biomass carbon(MBC) in various soils(the farmland,timberland and wasteland) in Northern Anhui are studied.The results show that the content of TOC,DOC and MBC obtains maximum value at topsoil and will decrease regressively with the deepening of soil layer depth.The ratio at content of DOC and MBC to TOC are 5.23%-13.45% and 3.09%-8.82% respectively.With the great influence of different exploiting manners imposing on organic carbon and active ingredients,the maximum content of TOC,DOC,MBC appears in timbered soil,then farmland is in the next,and wasteland takes the lowest.The comparison of ratio at content of DOC to TOC in various soils is timberlandfarmlandwasteland whereas it is farmlandtimberlandwasteland to MBC.Dynamics of the humic acid and trend of the change in content of total organic carbon tended to be similar.