he present paper studied the charactristics and functions of decomposer subsystem ofLeymus chinensis steppe in Inner Mongolia. The decompositions of litter of Leymus chinensis plant and materials in different phenological periods were determined by net-bag method. Themain results were as follows:1. The biomass of microorganisms and the activities of enzymes (protease and invertase)on the surface of the residues of young plants were higher than thatof old plants. The decomposing rate of young plants mate...