Cell‐Size‐Dependent Responses of Bacterial Communities to Warming in the Alpine Grasslands of the Qinghai‐Tibet Plateau

作者：Jie Liu, Lan Zhang, Hao Zou, Hao Shi, Junqiang Wang, Fei Xia, Yunfeng Yang · 发表于：Global Change Biology · 年份：2025 · DOI：10.1111/gcb.70285 · 被引用次数：5 · 研究领域：Microbial Community Ecology and Physiology、Gut microbiota and health、Genomics and Phylogenetic Studies

Cell size is a fundamental determinant of bacterial ecology, influencing community dynamics, physiological processes, and ecological interactions. However, the impacts of climate change-especially warming-on bacteria of varying cell sizes remain poorly understood, particularly in sensitive ecosystems such as alpine grasslands. In this study, we conducted an open-top chamber warming experiment (+1.3°C) to investigate how warming affects bacterial communities across four distinct cell size categories (< 0.4, 0.4-3.0, 3.0-5.0, and > 5.0 μm) in the alpine grasslands of the Qinghai-Tibet Plateau. Our results show that warming differentially impacts bacterial communities depending on cell size. Small bacteria (< 0.4 μm) were more sensitive to warming, with increased richness and diversity, while larger bacteria (3.0-5.0 μm) experienced a decline in both diversity and richness. These shifts were accompanied by compositional changes, particularly within the < 0.4 μm fraction, where phyla such as β-Proteobacteria, δ-Proteobacteria, Bacteroidetes, and Thermotogae decreased, while Actinobacteria increased. Additionally, warming decoupled the interactions between large bacteria and soil or plant components, while enhancing plant-bacterial coupling for small bacteria. Co-occurrence network analysis revealed that warming reduced the complexity and connectivity of small bacterial communities, making them less stable and more influenced by deterministic processes. In contrast, warming promot...