Soil aggregates regulate microbial drivers of phosphorus fractions under mowing and phosphorus addition

作者：Xiuping Li, Haiying Cui, Shanling Wang, Baoshuang Hu, Huiliang Zhai, Jiaxin Hu, Xia Peng, Muhammad Shakir, Wei Sun · 发表于：Frontiers in Microbiology · 年份：2025 · DOI：10.3389/fmicb.2025.1671636 · 被引用次数：3 · 研究领域：Soil Carbon and Nitrogen Dynamics、Soil and Water Nutrient Dynamics、Mycorrhizal Fungi and Plant Interactions

Microorganisms play a vital role in maintaining ecosystem structure and function by mediating the dynamics of phosphorus (P) fractions under land-use intensification. However, microbial properties vary considerably across different soil aggregate sizes, making it challenging to determine how microorganisms regulate P fractions in response to mowing and P addition. To address this knowledge gap, we conducted an 8-year field study in a meadow steppe in Northeast China to examine the effects of mowing, P addition, and their interaction on P fractions across soil aggregate sizes. The results indicated that the interaction between mowing and P addition increased total P across soil aggregates. Specifically, this interaction enhanced available P (the sum of labile Pi and labile Po) by 74.13, 55.01, and 9.50% in large macroaggregates (LMA), small macroaggregates (SMA), and microaggregates (MA), respectively. In LMA, increases in moderately labile Pi, moderately labile Po, and residual P were driven by a decreased microbial biomass carbon to microbial biomass phosphorus (MBC: MBP) ratio, which was reduced by P addition. In SMA, P addition and mowing increased labile Po, labile Pi, and moderately labile Pi by enhancing plant richness. In MA, P addition not only increased labile Po and moderately labile Pi by stimulating plant belowground biomass (BGB) but also enhanced residual P through elevated alkaline phosphatase (ALP) activity. These findings highlight the critical role of soil a...