Desertification can pose threats to global socioeconomic development, ecological and environmental safety, human health and survival. Species and function diversity are two aspects of biodiversity, and soil fungal community are important decomposers, playing important roles in element cycling. A field experiment was performed along a desertification gradient in an alpine steppe, the Northern Tibet to investigate how can the species α-diversity and composition, function α-diversity and composition change. No significant differences of species α-diversity were observed among the five desertification treatments. A significant difference of the function α-diversity was only observed between the light and severely heavy desertification treatments. Significant differences of species composition were observed between any two of the five desertification treatments. Function composition between not all any two treatments had significant differences. The changes of species and function composition along the desertification gradient were mainly attributed to BGB:AGB, 0.15–2 mm and < 0.15 mm soil particles. Two phyla (Glomeromycota and Zygomycota) and two trophic modes (Symbiotroph and Pathotroph-Saprotroph) were the differentially taxa and ecological functions, respectively, which indicated that the two phyla and trophic modes can be used to indicate desertification gradient, and combination of species and function composition may be better in monitoring desertification conditions.

荒漠化可能对全球社会经济发展、生态和环境安全、人类健康和生存构成威胁。物种和功能多样性是生物多样性的两个方面，土壤真菌群落是重要的分解者，在元素循环中发挥着重要作用。在藏北高寒草原沿沙漠化梯度进行野外试验，研究物种α-多样性和组成、功能α-多样性和组成如何变化。5个荒漠化处理之间没有观察到物种α多样性的显着差异。仅在轻度和重度荒漠化处理之间观察到函数α-多样性的显着差异。在五种荒漠化处理中的任何两种之间观察到物种组成的显着差异。并非所有两种处理之间的功能组成都有显着差异。沿沙漠化梯度的物种和功能组成的变化主要归因于 BGB:AGB、0.15-2 mm 和 < 0.15 mm 土壤颗粒。两门（球囊菌门和接合菌门)和两种营养模式(共生和腐生)分别是不同的分类群和生态功能，表明两种门和营养模式可用于指示荒漠化梯度，物种和功能组成的组合可能更好地监测荒漠化状况。