Grazing-induced abiotic and resource changes drive distinct responses of soil bacterial and fungal community in temperate meadow steppe: Implications for carbon dynamics

作者：Cuixia Jiang, Xiaoping Xin, Kai Xue, Zhigang Zhao, Weixing Liu, Haonan Guo, Feng Liu, Hui Li, Zihao Li, Yali Si, Ruirui Yan · 发表于：Geoderma · 年份：2025 · DOI：10.1016/j.geoderma.2025.117451 · 被引用次数：5 · 研究领域：Soil Carbon and Nitrogen Dynamics、Mycorrhizal Fungi and Plant Interactions、Forest Ecology and Biodiversity Studies

• Our results demonstrate distinct patterns of changes in bacterial and fungal community. • Bacterial community showed a clear succession and were more sensitive to abiotic conditions than resource limitations. • Fungal community revealed a more discrete shift, limited by resources and structured by bottom-up forces. • Both bacterial and fungal composition shifted towards more oligotrophic and less copiotrophic with grazing increased. • Heavy grazing lead to a depleted substrate and inhibited ecosystem respiration, change soil carbon cycling and stocks. Soil microbial communities play a crucial role in maintaining grassland ecosystem functions and are strongly influenced by livestock grazing. However, the long-term responses and driving mechanisms of soil microbial communities to grazing intensity gradients, remain largely unexplored. In this study, we investigated the mechanism of different grazing intensities (i.e., ungrazed, light, moderate and heavy grazing) affect the diversity and composition of soil bacteria and fungi in the Hulunbuir Leymus chinensis meadow steppe. Using a Bipartite network to represent indicative species shifts, bacterial community presented a clear succession along the grazing intensity gradient, likely linked to soil abiotic conditions (e.g. soil temperature, silt). In contrast, fungal community exhibited a more discrete shift along the grazing intensity gradient, challenging the traditional view that fungal community is more stable under disturban...