The Seasonal Dynamics And Ecological Distribution Of Alpine Shrubs Soil Microorganism In Easten Qilian Mountain

As an important decomposer in the alpine shrubs grassland ecosystem, which affected the development and succession of the grassland through microcosmic view of the system, the soil microorganisms play vital roles in substance cycling and energy conversion. Thus, studies on soil microorganisms in the alpine shrubs grassland ecosystem can supply the microbiological theory evidences for improving soil conditions and increasing productivity of shrubs grassland in the alpine shrub(?) grassland ecosystem.According to the different vegetation types in Tian Zhu county of Gan Su province, three representative alpine shrubs grassland samples were selected for research.,that was sample 1.Rhododendron fruticosa shrubs,sample 2.Salix cupularis fruticosa shrubs and sample 3. Dasiphoru fruticosa shrubs,all of which were common pasturage. The quantity, community diversity, seasonal dynamics, zoological distribution and physiological floraof of soil microorganism as well as the relationship between soil microorganisms and soil environment were studied and analized. The results were as follows: 1. Seasonal dynamics of soil microorganism quantitiesA significant change in soil community microorganism quantities could be seen. The number of microorganism in November and May were the highest,while it was less in September and July. The change of all kinds of microorganisms in different shrubs were showed as follows. (1)Bacteria: Bacteria were absolutely dominant regardless of the months and sites during all the year. A regulation of total bacterial quantities that Salix cupularis fruticosa shrubs had the most, and then Rhododendron fruticosa shrubs, Dasiphoru fruticosa shrubs had the least could be found. Its annual average proportion in each total soil microorganism quantities were 88.38%, 82.01%, 80.67%, respectively. Among the three sites, the seasonal fluctuation was the lightest in Salix cupularis fruticosa shrubs (10.06% ) while the strongest happened in Dasiphoru fruticosa shrubs (41.14%) .(2)Fungi: The total number of fungi during the year was most in Rhododendron fruticosa shrubs, followed by Salix cupularis fruticosa shrubs, and Dasiphoru fruticosa shrubs was the least in different shrubs with the annual average proportion in total soil microorganisms 0.34%, 0.17%, 0.21%. Among the three sites, the seasonal fluctuation was the most significant (0.52 % ) in Rhododendron fruticosa shrubs, and Salix cupularis fruticosa shrubs (0.08 % ) was the lightest.(3) Actionmyces: Its annual average proportion against total soil related...