The Diversity And Ecological Distribution Of AM Fungi In Desert Biological Soil Crust

The distribution of Abrbuscular mycorrhiza fungi (AMF) is extensive in the natural world, and it is forming symbiosis with higher plants in land ecosystem and generates Abrbuscular mycorrhiza. The composition and diversity of AM fungi has great significance in adjusting the construct of the plant community, determining the diversity of plants and the productivity of ecosystem and maintaining the function and stability of ecosystem. Desert biological soil crust is the most distinct micro-natural landscape, symbiotically consisting of a complex biological soil layer with liverwort, lichen, alga and fungi, which has some influence on the deversity of ecosystem in dry areas and maintaining of systemic function and evolution process of vegetation. Therefore, this paper is helpful to the research on AM fungi deversity on biological soil crust in Erdos areas and its correlation with the species of moss and soil factors by probing into the deversity and symbiotic chcracteristics of AM fungi of biological soil crust. Besides, it will further uncover the construct and function of desert biological soil crust and provide experimental data for the construction of plant vegetation on desert soil. The findings are as following:1. The species of moss plants in desert biological soil crust in Erdos areas is comparatively few and the composition of communities is simple. The regular species are: Bryum argenteum Hedw, Bryum dichotomum Hedw, Pterygoneurum subsessible (Brid.) Jur.). There is a correlation between AM fungi and moss plants on desert biological soil crust in Erdos areas, because hyphae was found in rhizoids when observing the structure of hyphae and vesicles in the moss stem and leaf tissues collected. And AM fungi spores distributes in the soil layer of biological soil crust.2. The abundance AMF species was found in biological soil crust of Erdos. 27 species of 4 genera of AM fungi are seperated from 392 soil samples of 7 sampling lands under investgation, of which there are 19 Glomus, 4 Acaulospora, 3 Diversispora and 1 Scutellospora, and of which there are 12 unidentified species, 3 Acaulospora and 9 Glomus. The dominant species mainly are G. caledonium,G. Constrictum,G. convolutum,G. Deserticola, ect.3. A distinct seasonal change of the distribution of AM fungi is found in the desert biological soil crust in Hangjin. The index of AM fungi changing trend of spores species, spores density, species richness and Shannon-wienner index of AM fungi in sampling land HX, HB, HS are: AMF spores density varies from month from high to low, August>July>September>October; species richness is the highest in August and drops on September and October; shnnnon-winner index presents as August,October>September> July. The variety of soil layer in the same month changes as: The soil of non biological soil crust of Artemisia ordosica >The soil of under biological soil crust >The soil of biological soil crust >The soil of non biological soil crust and plant vegetation.4. The test of soil factors show: the content of total Phosphorus.,Avialable Phosphorus,Total Nitrogen,Alkali-decomposed Nitrogen and Organic Matter in the soil layer of biological soil crust is higher than under biological soil crust, but pH indicator is lower.5. There is a significant correlation (p<0.05 ) between the AM fungi spores density, species richness,diversity index and the soil component, but the index in different sampling lands, different soil layers and different month are also different. There is a significant correlation (p<0.05) between the AM fungi spores density and plant density of Artemisia ordosica community.