Effects Of Different Land Use And Soil Heterogeneity To Decomposition Rate Of Litter In Inner Mongolia Grassland

The response of litter decomposition to different land use patterns in grassland ecosystem is the key to understand the grassland nutrient cycling and dynamics,and the basis to develop sustainable management measures.In a five-year long grassland experiment in the steppe of Inner Mongolia,We studied the litter decomposition of three dominant plant species Leymus chinense,Stipa krylovii and Cleistogenes squarrosa,with the aim to examine the effects of three land use types and in situ and displacement on litter decomposition.The results showed that:(1)Grassland soil properties under different land use of grazing,mowing and enclosing altered but no significant effect on the decomposition rate of litter;In contrast,the soil properties among sampling plots were significantly related with litter decomposition rate.This result suggests that the inherent heterogeneity of the soil has a greater impact on litter decomposition rate than that of different land use over five-years.(2)For the litter of different plant species,the lower the proportion of lignin,the faster the decomposition rate.The result also showed no significant difference in litter decomposition rate between the in situ and dislocated.It did not show the Home-field advantage of litter decomposition.The conclusion and its causes need to be further verified by a longer period experiment.This study provides basic scientific data for understanding the effects of land use and soil heterogeneity nutrient cycling of grassland ecosystem.