Response of Soil Microbial Biomass Carbon to Litter Input in Forests
Microbial biomass carbon(MBC)is the most active and sensitive soil carbon fractions.Lit-ter input provides enough fresh carbon sources for soil microorganisms,which is an important carrier of forest soil biogeochemical cycle.Different litter types lead to different quantity and quality as well as chemical compositions of plant litter,which directly affect litter decomposition and soil MBC content.Therefore,it is of great significance to evaluate the changes in soil MBC response under litter addition and removal in different forest ecosystems.In this study,we complicated 630 paired data from 74 published research articles to assess the effects of litter addition and removal on soil MBC response from the aspects of litter type,forest type and experiment time.The results showed that different litters had different effects on soil MBC response.Litter addition increased soil MBC content by 14.4%,while litter removal and both roots and litter removal reduced soil MBC content by 5.9%,12.1%and 13.5%,respectively.The effect of root litter removal on soil MBC content was 2.1 times higher than that of leaf litter.Forest type significantly affected the response of soil MBC content to litter input,and these changes in plantations(22.8%),deciduous(26.2%)and broadleaved forests(14.9%)were higher than those in primary(8.9%),evergreen(8.4%)and coniferous forests(9.9%),respectively.The response of soil MBC increased rapidly(15.8%)within one year of litter input,then decreased gradually with experimental period.This effect decreased over time after litter removal.Results suggest that litter input is an important source of soil MBC,and the contribution of roots is about two times higher than that of leaf litter input.Moreover,the change in soil MBC was more sensitive to high-quality litter input,which is of great significance for further understanding the microbially mediated biogeo-chemical processes in terrestrial ecosystems.
NETL
NSTL
万方数据
