The Soil Microbial Ecological Characteristics And Soil Microelements Changed Trait Of Artifical Vegetation In Drifting Desert

In the center of Taklimakan desert in the extremely arid region , Artificial vegetation has been set up by saline water (4～5g/l),which have reformed ecological environment ,enhanced the form of Blown Sand Soil .The Blown Sand Soil properties have changed much. The soil microorganism amount and activities have improved . The contents and distribution of soil microelements follow certain regularity in the process of soil-forming. Our researches showed: (1)There are a small quantities of microbes and a low microorganism activities in drifting sand dunes .After the Artificial vegetation has been set up ,the soil microbial population is in large number and varied with the forest ages ,the microorganism activities have a remarkable improvement .(2)The amount of bacteria is highest, the secondary is actinomycies ,the last is fungus .In bacteria ,bacillus have a high percent.(3)After the Artificial vegetation has been set up, the amount of physiological group of the microorganism have a greatly improved. The amount of ammonifiers is largest. The large number of bacteria can produce amylase.(4)The amount of microorganism in summer were different from autumn. (5)The sand-fixing plants planted on drift sand dunes have well-developed rhizosphere microorganisms. The amount of rhizosphere microorganisms is more than beyond it. (6)The total contents of afforestation plots are not significant differences with drift sand dunes; Available contents of plots are higher than drift sand dunes. The development of Blown Sand Soil is still on primal period. The contents of soil microelement of each plots are low, which reason is the low contents of drifting sand. (7)The contents of soil microelement of afforest plots are increased with ages. In the plots of same age, the content of grassplot is the most.