新疆天然胡杨林土壤微生物多样性的研究

为了探明新疆天然胡杨林土壤微生物类群的生态分布情况，该文研究了幼龄林、中壮林、过熟林、衰亡林4个不同发育阶段胡杨林内的土壤细菌、真菌及放线菌的数量和类群组成.结果表明:4种林地内土壤微生物的数量和种类组成有明显差异，不同土壤层的微生物数量随着土层深度的增加逐渐减少，其中以31～40 cm范围内为最少.细菌在不同胡杨林的各个土层中均有分布，数量明显高于放线菌和真菌，而在部分林地内的土层中，没有分离到放线菌和真菌.在林地内共分离出土壤真菌11属，其中，曲霉属为4个不同发育阶段胡杨林土壤中的优势菌属. 

Diversity of soil microorganism in the natural Populus euphratica forests in Xinjiang, northwestern China

In order to better understand the distribution of soil microorganism in the Populus euphratica forests in Xinjiang of northwestern China,this paper studies and compares the population and quantity of bacteria,fungi and actinomycetes in the soil of four kinds of P.euphratica forests,which are young forests,middle-aged forests,over-mature forests and effete forests.The results showed that there were evident differences in the microorganism biomass and composition rates of four growing stages of natural P.euphratica forests in Xinjiang,and the dominant and special microorganism existed in all different layers of soil section.The vertical distribution showed that the microorganism biomass decreased with the increase of soil depth,and the population of microorganism was the least in 31-40 cm depth of soil.The microorganism consisted of bacteria,which were the chief content and distributed widely,and actinomycetes as well as fungi,which were scarce in some layers of soil section.Aspergillus was the dominant genus among the 11 genera of fungi isolated from soil in the different growing stages of P.euphratica forests.