Long‐term straw mulching alleviates microbial nutrient limitations and increases carbon‐use efficiency within aggregates

作者：Yan Li, Xuechen Zhang, Meng Li, Jiaxin Liu, Kuandi Zhang, Ziyan Li · 发表于：Soil Use and Management · 年份：2024 · DOI：10.1111/sum.13058 · 被引用次数：7 · 研究领域：Soil Carbon and Nitrogen Dynamics、Irrigation Practices and Water Management、Composting and Vermicomposting Techniques

Abstract Long‐term straw mulching was known to change soil nutrient content, aggregate distribution and extracellular enzyme activities. However, the impact of long‐term straw mulching on microbial nutrient limitations and carbon‐use efficiency (CUE st ) within aggregates remains unclear. To fill the gap, we conducted a 10‐year field experiment in a semi‐arid region and used an ecoenzymatic stoichiometry model to quantify microbial resource limitations in soil aggregates under long‐term mulching. We studied the effects of two mulching measures (plastic film mulching [FM] and straw mulching [SM], with no mulching as the control [CK]) on the nutrient content and limitations within aggregates. The results show that compared with FM, SM increased the proportion of aggregates to larger >2 mm and decreased the proportion of aggregates in the 2–0.25 mm classes. Additionally, FM resulted in carbon (C) and phosphorus (P) limitations in the soil, particularly in the >2 mm class, while SM alleviated these constraints. This effect was primarily attributed to the increase in soil organic carbon (SOC) and microbial biomass carbon content (C m ), especially the enhanced carbon content associated with larger aggregates (>2 mm) and the increased activities of carbon–nitrogen (C–N)‐acquiring enzymes. SM also resulted in high CUE st by influencing microbial P limitation. Random forest analysis indicates that soil abiotic factors, particularly SOC and total nitrogen (TN), were the main ...