全球变化研究组知识库

Background and aimsSoil microbes are essential in regulating ecosystem structures and functions. However, few studies have simultaneously explored the distribution patterns of microbial communities in fungi, bacteria, and protists across various climatic regions.MethodsWe conducted a regional-scale field investigation in tropical rainforest, tropical valley savanna, subtropical forest, and cold temperate forest to explore the spatial patterns and regulating factors of soil microbial communities from tropical to cold temperate regions.ResultsThe tropical rainforest exhibited the highest diversity of fungi, bacteria, and protists. In contrast, tropical valley savannas had the lowest bacterial and protistan diversity, while subtropical and cold temperate forests had the lowest fungal diversity. These spatial patterns of microbial diversity were primarily influenced by soil properties, such as soil organic carbon (SOC), dissolved organic carbon (DOC), total nitrogen (TN), and pH. Our results also indicated that most microbial phyla were influenced by both soil properties and climate factors, with mean annual temperature (MAT) and potential evapotranspiration (PET) playing a particularly significant role in shaping fungal and bacterial community composition. In contrast, soil clay content, aridity and moisture availability had a more pronounced effect on protistan composition compared to their effects on fungi and bacteria.ConclusionThese results imply that climatic factors exert a greater impact on microbial community composition than on microbial diversity. Our findings enhance the understanding of soil microbial community patterns and underscore the role of climate-driven shifts in community composition in regulating soil biogeochemical processes, with potential consequences for ecosystem functions under global change.