In-depth microbial community characterization, a community-level metabolic function analysis, and biogeochemical assessments of residues were performed to understand the principles governing microbial community assembly in wheat straw during decomposition with different N fertilization rates in soil. We identified a suite of decomposition-associated bacterial and fungal groups in straw that contribute to C and N cycling. The decomposition-associated microbial community in straw is likely mainly derived from the original straw, and the bacterial and fungal communities showed different patterns along with the decomposition. Overall, the microbial community composition and function were not substantially affected by the N fertilization rate, but N fertilization significantly increased the straw microbial assembly speed and had significant effects on the abundances of certain taxa and C- and N-related genes, leading to different decomposition rates of straw under different N fertilization rates. Furthermore, the straw quality, especially dissolved organic C (DOC) and lignin, accounted for most observed effects on microbial community development and decomposition. The results provide new insight into the roles of the microbial community in straw during crop residue decomposition for nutrient cycling in farmland ecosystems.

中文翻译：

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不同施氮处理小麦秸秆分解过程中微生物群落组装及代谢功能

进行了深入的微生物群落表征、群落水平代谢功能分析和残留物的生物地球化学评估，以了解在土壤中不同施氮率下小麦秸秆分解过程中微生物群落组装的原理。我们在稻草中发现了一组与分解相关的细菌和真菌群，它们有助于 C 和 N 循环。秸秆中与分解相关的微生物群落可能主要来源于原始秸秆，细菌和真菌群落随着分解呈现出不同的模式。总体而言，微生物群落组成和功能不受施氮量的显着影响，但施氮显着提高了秸秆微生物的组装速度，对某些分类群和碳氮相关基因的丰度有显着影响，导致不同施氮率下秸秆的分解速率不同。此外，秸秆质量，尤其是溶解有机碳 (DOC) 和木质素，对微生物群落发展和分解的影响最大。这些结果为了解秸秆中微生物群落在农田生态系统中作物残留物分解过程中的养分循环中的作用提供了新的见解。占观察到的对微生物群落发展和分解的大部分影响。这些结果为了解秸秆中微生物群落在农田生态系统中作物残留物分解过程中的养分循环中的作用提供了新的见解。占观察到的对微生物群落发展和分解的大部分影响。这些结果为了解秸秆中微生物群落在农田生态系统中作物残留物分解过程中的养分循环中的作用提供了新的见解。