Altered precipitation and nighttime warming reshape the vertical distribution of soil microbial communities

作者：Suo Liu, Jingyi Ru, Xue Guo, Qun Gao, Sihang Deng, Jiesi Lei, Jian Song, Changchun Zhai, Shiqiang Wan, Yunfeng Yang · 发表于：mSystems · 年份：2025 · DOI：10.1128/msystems.01248-24 · 被引用次数：7 · 研究领域：Microbial Community Ecology and Physiology、Polar Research and Ecology、Gut microbiota and health

ABSTRACT Soil depth determines microbial community composition. Yet, it remains largely unexplored how climate changes affect the vertical distribution of soil microbial communities. Here, we investigated the effects of altered precipitation and nighttime warming on microbial communities in the topsoils (0–20 cm) and subsoils (20–50 cm) of a temperate grassland in Inner Mongolia, China. As commonly observed under nutrient scarcity conditions, bacterial and fungal α-diversity and network complexity decreased with soil depth. However, protistan α-diversity and network complexity increased, which was attributed to less niche overlap and smaller body size. Strikingly, the slopes of linear regressions of microbial α-diversity/network complexity and soil depth were all reduced by altered precipitation. Microbial community composition was significantly influenced by both depth and reduced precipitation, and to a lesser extent by nighttime warming and elevated precipitation. The ribosomal RNA gene operon ( rrn ) copy number, a genomic proxy of bacterial nutrient demand, decreased with soil depth, and the percentages of positive network links were higher in the subsoil, supporting the “hunger game” hypothesis. Both reduced precipitation and nighttime warming decreased the rrn copy number in the subsoils while increasing the percentages of positive links, enhancing potential niche sharing among bacterial species. The stochasticity level of bacterial and fungal community assemblies decr...