State Key Laboratory of Crop Stress Biology in Arid Areas, Shaanxi Key Laboratory of Agricultural and Environmental Microbiology, College of Life Sciences, Northwest A&F University, Yangling, China.
State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China.
Mol Ecol. 2021 Sep;30(17):4338-4348. doi: 10.1111/mec.16047. Epub 2021 Jul 12.
Uncovering the linkages between community assembly and species diversity is a fundamental issue in microbial ecology. In this study, a large-scale (transect intervals of 1257.6 km) cross-biome soil survey was conducted, which ranged over agricultural fields, forests, wetlands, grasslands and desert, in the arid regions of northwest China. The aim was to investigate the biogeographic distribution, community assembly and species co-occurrence of soil fungi. The fungal communities in agricultural soils exhibited a steeper distance-decay slope and wider niche breadths, and were more strongly affected by stochastic assembly processes, than fungi in other natural habitats. A strong relationship was revealed between soil fungal richness and community assembly in arid ecosystems, with the influence of stochastic assembly processes decreasing with increasing fungal richness. Moreover, aridity was the most important environmental factor influencing fungal richness, β-diversity and species co-occurrence patterns. Specifically, the predicted increase in arid conditions will probably reduce fungal richness and network complexity. These findings represent a considerable advance in linking fungal richness to mechanisms underlying the biogeographic patterns and assembly processes of fungal communities in arid ecosystems. These results can thus be used to forecast species co-occurrence and diversities pattern of soil fungi under climate aridity and land-use change scenarios.
揭示群落组装和物种多样性之间的联系是微生物生态学的一个基本问题。本研究进行了大规模的（样带间隔为 1257.6 公里）跨生物群落土壤调查，范围包括中国西北干旱地区的农田、森林、湿地、草原和沙漠。目的是调查土壤真菌的生物地理分布、群落组装和种间共存。与其他自然生境中的真菌相比，农业土壤中的真菌群落表现出更陡峭的距离衰减斜率和更宽的生态位宽度，并且更受随机组装过程的影响。在干旱生态系统中，土壤真菌丰富度与群落组装之间存在很强的关系，随着真菌丰富度的增加，随机组装过程的影响减小。此外，干旱是影响真菌丰富度、β多样性和种间共存模式的最重要环境因素。具体来说，预计干旱条件的增加可能会降低真菌丰富度和网络复杂性。这些发现代表着将真菌丰富度与干旱生态系统中真菌群落的生物地理格局和组装过程的机制联系起来的重大进展。因此，这些结果可用于预测气候干旱和土地利用变化情景下土壤真菌的种间共存和多样性模式。
