Zhang Xiumin, Zhang Huayong, Wang Zhongyu, Tian Yonglan, Tian Wang, Liu Zhao
Research Center for Engineering Ecology and Nonlinear Science, North China Electric Power University, Beijing 102206, China.
Theoretical Ecology and Engineering Ecology Research Group, School of Life Sciences, Shandong University, Qingdao 266237, China.
Microorganisms. 2024 Aug 2;12(8):1577. doi: 10.3390/microorganisms12081577.
Soil nitrogen (N) mineralization typically governs the availability and movement of soil N. Understanding how factors, especially functional genes, affect N transformations is essential for the protection and restoration of forest ecosystems. To uncover the underlying mechanisms driving soil N mineralization, this study investigated the effects of edaphic environments, substrates, and soil microbial assemblages on net soil N mineralization in boreal forests. Field studies were conducted in five representative forests: forest (LF), forest (BF), mixed forest of and (MF), forest (SF), and var. forest (MPF). Results showed that soil N mineralization rates (R) differed significantly among forests, with the highest rate in BF ( < 0.05). Soil properties and microbial assemblages accounted for over 50% of the variability in N mineralization. This study indicated that soil environmental factors influenced N mineralization through their regulatory impact on microbial assemblages. Compared with microbial community assemblages (α-diversity, Shannon and Richness), functional genes assemblages were the most important indexes to regulate N mineralization. It was thus determined that microbial functional genes controlled N mineralization in boreal forests. This study clarified the mechanisms of N mineralization and provided a mechanistic understanding to enhance biogeochemical models for forecasting soil N availability, alongside aiding species diversity conservation and fragile ecosystem revitalization in boreal forests.
土壤氮（N）矿化通常控制着土壤氮的有效性和移动性。了解各种因素，特别是功能基因，如何影响氮转化对于森林生态系统的保护和恢复至关重要。为了揭示驱动土壤氮矿化的潜在机制，本研究调查了土壤环境、底物和土壤微生物群落对北方森林土壤净氮矿化的影响。在五个具有代表性的森林中进行了实地研究：落叶松森林（LF）、白桦森林（BF）、落叶松和白桦混交林（MF）、云杉森林（SF）以及蒙古栎变种森林（MPF）。结果表明，不同森林之间的土壤氮矿化速率（R）存在显著差异，其中BF的速率最高（P < 0.05）。土壤性质和微生物群落解释了氮矿化变异的50%以上。本研究表明，土壤环境因素通过对微生物群落的调节作用影响氮矿化。与微生物群落组合（α多样性、香农指数和丰富度）相比，功能基因组合是调节氮矿化的最重要指标。因此确定微生物功能基因控制着北方森林中的氮矿化。本研究阐明了氮矿化机制，并为增强预测土壤氮有效性的生物地球化学模型提供了机理认识，同时有助于北方森林的物种多样性保护和脆弱生态系统恢复。
