Abstract:

This paper is a perliminary study of the decomposition of litter of the Xilinguole grassland major plants Aneurolepidium chinense and Stipa grandis and the dynamic changes of biomass of various of decaring microorganisms, and the effect of soil biology with decomposing litter.

The study results shows:

1. The decomposing rate of litter of Aneurolepidium chinense and Stipa grandis stems and leaves is comparatively slow. The weight loss rates were respectively 15.9%, 16.9% and 21.5% on soil aboveground; In soil underground they were 21.4%, 23.5% and 26.5% in the past two years. And the decomposing rate became more and more slow with the passage of time. The decomposing rate of litter in soil underground is higher than that on the soil aboveground.

2.In the process of decomposition of litter,the biomass of the various groups of microorganims increased markedly. Compared with microbial biomass sticking to the surface of litter, progress increase ranged from 10 to 300 times.

3. The ratio of the carbon content to the nitrogen content of the rotting residues decreased with the progress of decomposition.

4. Decomposition of litter could stimulate the increase of microbiological activity in soils of different depths, and an increase of soil organic content as well.