In arid and semi-arid ecosystems, the biocrust serves as an important biological interface in the topsoil. Although the biocrust and vascular plant and soil are closely related, microbial diversity and functional characteristics in biocrusts of different vegetation communities and soil habitats, especially in watershed conditions, is poorly understood. In this study, biocrust samples were collected from two different soil substrate habitats, the loess and the aeolian sandy soil, as well as three plant communities consisting of Stipa bungeana, Artemisia ordosica, and Populus simonii, with the farmland soil acting as the control at the small watershed scale in the interlaced water and wind eroded area of Northern Shaanxi, China. To characterise the microbial diversity and functionality within biocrusts, a total of 4705 and 219 16S and 18S rDNA OTUs, respectively, were classified using high-throughput sequencing. Proteobacteria, Actinobacteria, and Bacteroidetes were dominant in prokaryotic community, whereas Ascomycota and Basidiomycota were dominant in fungal community in biocrusts. Principal coordinate analysis and hierarchical clustering demonstrated significant differences in prokaryotic and fungal communities between farmland soil and biocrusts, and soil parent materials could be a major factor in shaping the difference in the microbial communities of biocrusts relative to the vegetation types. Soil pH and carbon were dominant environmental factors that affected the prokaryotic and fungal communities in biocrusts. Hence, we demonstrated that the biocrust can significantly improve the topsoil properties in the study region, while their prokaryotic and fungal communities are largely determined by soil properties and environmental parameters.

在干旱和半干旱生态系统中，生物结皮是表土中重要的生物界面。尽管生物结皮和维管植物与土壤密切相关，但人们对不同植被群落和土壤生境，尤其是流域条件下的生物结皮中的微生物多样性和功能特征知之甚少。在这项研究中，从黄土和风沙土两种不同的土壤基质栖息地以及由白针茅、油蒿和杨树组成的三个植物群落中采集了生物结皮样品。, 以农田土壤作为控制在陕北水风交织区小流域尺度。为了表征生物结皮内的微生物多样性和功能，使用高通量测序分别对总共 4705 个和 219 个 16S 和 18S rDNA OTU 进行了分类。变形菌门、放线菌门和拟杆菌门在原核生物群落中占优势，而子囊菌门和担子菌门在生物结皮的真菌群落中占优势。主坐标分析和层次聚类表明农田土壤和生物结皮之间的原核和真菌群落存在显着差异，土壤母质可能是形成生物结皮微生物群落相对于植被类型差异的主要因素。土壤 pH 值和碳是影响生物结皮中原核和真菌群落的主要环境因素。因此，我们证明了生物结皮可以显着改善研究区域的表土特性，而它们的原核和真菌群落很大程度上取决于土壤特性和环境参数。