Spatio-temporal distribution of arbuscular mycorrhizal fungi in the rhizosphere of Ammopiptanthus mongolicus

In order to explore the relationship between the annual variation of AM fungal species diversity and ecological functions of soil factors in the rhizosphere of Ammopiptanthus mongolicus,soil samples in the rhizosphere of A.mongolicus were collected from three samples sites(Yinchuan,Shapotou and Minqin)and divided into five layers on the basis of depth,from top to bottom:0—10,10—20,20—30,30—40,40—50cm in July2012 and 2013.In this study,36 species of AM fungi were isolated from five genera isolated in three sampling sites.Among them,16 species belonged to Glomus,13 to Acaulospora,three to Funneliformis,three to Scutel-lospora and one to Diversispora.AM fungal species composition,spore density and species richness were significantly different between different years and different layers.AM fungal species diversity was closely related to the soil environments.The correlation analysis showed that spore density had a significant positive correlation with soil acid phosphatase and total glomalin,species abundance had a significant positive correlation with soil urease,organic matter and available N.The results showed that the AM fungal species diversity had obvious spatial heterogeneity and closely related with soil environments.AM fungal species diversity and distribution could be used as an ecological indicator to detect and evaluate the desert environment state.