More sensitive microbial responses to the interactive effects of warming and altered precipitation in subsoil than topsoil of an alpine grassland ecosystem

作者：Qi Qi, Shijie Ning, Xue Guo, Jianshu Zhao, Renmao Tian, Haoran Gui, Jin He, Hao Wang, Zhenhua Zhang, Konstantinos T. Konstantinidis, Qun Gao, Yuxin Wang, Shunyi Li, Weishu Zhao, Yunfeng Yang, Jizhong Zhou · 发表于：Global Change Biology · 年份：2024 · DOI：10.1111/gcb.17487 · 被引用次数：24 · 研究领域：Microbial Community Ecology and Physiology、Gut microbiota and health、Soil Carbon and Nitrogen Dynamics

Subsoil is a large organic carbon reservoir, storing more than half of the total soil organic carbon (SOC) globally. Conventionally, subsoil is assumed to not be susceptible to climate change, but recent studies document that climate change could significantly alter subsoil carbon cycling. However, little is known about subsoil microbial responses to the interactive effects of climate warming and altered precipitation. Here, we investigated carbon cycling and associated microbial responses in both subsoil (30-40 cm) and topsoil (0-10 cm) in a Tibetan alpine grassland over 4 years of warming and altered precipitation. Compared to the unchanged topsoil carbon (β = .55, p = .587), subsoil carbon exhibited a stronger response to the interactive effect of warming and altered precipitation (β = 2.04, p = .021), that is, warming decreased subsoil carbon content by 28.20% under decreased precipitation while warming increased subsoil carbon content by 18.02% under increased precipitation.Furthermore, 512 metagenome-assembled genomes (MAGs) were recovered, including representatives of phyla with poor genomic representation. Compared to only one changed topsoil MAG, 16 subsoil MAGs were significantly affected by altered precipitation, and 5 subsoil MAGs were significantly affected by the interactive effect of warming and precipitation. More than twice as many populations whose MAG abundances correlated significantly with the variations of carbon content, components and fluxes were obser...