Abstract: Drought and nitrogen input are profoundly influencing most life on Earth and the substance cycling in forest ecosystems in the Anthropocene, with consequences on global carbon balance and feedback on climate changes. Soil microorganisms drive biogeochemical cycling and key ecological processes, with central role and global importance in climate change biology. Here, we reviewed the research in the area of the effects of drought and nitrogen deposition on soil bacteria and mycorrhizal fungi in forest ecosystems. We proposed that future studies should focus on how microbial diversity, activity, and ecological functioning respond to multiple global change factors and their interactions; how subtropical forest ecosystems respond to global changes on the basis of establishment of the long-term field experimental station; the interaction of different soil biological guilds; utilizing microbial big data to construct the relevant mechanistic models. Taken together, based on improved understanding of the responses of soil microbial diversity and community composition to global changes, further research may subsequently focus on manipulating the microbial communities to enhance forest management, ecological resources protection, and environmental sustainability. This review would provide some critical theoretical basis for the microbial strategy in mitigating climate change in future.

Key words: nitrogen deposition, drought, mycorrhizal fungi, climate change, forest ecosystem, soil microorganism