Dynamics of Soil Microorganism and Enzyme Activity in Typical Steppe of Restoration Succession Process

Natural grasslands were enclosed during growing seasons for selected years as research objects.Dynamics of soil microorganisms and enzyme activities in typical steppe during restoration processes were studied for discussing correlations among soil microorganisms,enzyme activities,vegetation characteristics and soil nutrients.Results showed that the number of soil bacteria,actinomycetes and fungi increased,soil enzyme activity enhanced,and soil microbial biomass C,N increased significantly(P0.05) in 0~30 cm soil layer after 7,10,13 and 20 years enclosure compared with continuous grazing and increased gradually with enclosure period increasing.The change of soil microorganism and enzyme activity in typical steppe during restoring processes was basically identical with the change of vegetation characteristics and soil nutrient which showed a positive correlation.