Abstract Warming and nitrogen (N) deposition are two important aspects of environmental change influencing plants, microbes, and soil processes. Despite the crucial role of arbuscular mycorrhizal (AM) fungi in terrestrial ecosystems, how warming and N addition interactively affect the AM fungal community remains poorly understood. We conducted a 3-year field experiment to examine the effects of soil warming (+5 ℃) and N (40, 80 kg N ha−1 y−1, as LN and HN, respectively) addition on the soil AM fungal community composition in a 4-year-old Cunninghamia lanceolata plantation. The results indicated that warming, regardless of N addition, significantly decreased AM fungal diversity and altered AM fungal community composition, while N addition alone had only minor effects. More importantly, the changes of soil AM fungal diversity and community composition were greater in the warming plus N addition treatments than in the warming-only treatment, indicating that N addition intensified the effects of warming on the soil AM fungal community. Warming altered the soil AM fungal community composition, with decreases in the abundance of Glomeraceae and increases in the abundances of Ambisporaceae, Acaulosporaceae, Paraglomeraceae and Gigasporaceae. Furthermore, warming and N addition significantly increased root mycorrhizal colonization, with the greatest increase under the warming plus HN treatment. Altogether, our results suggest that warming predominantly altered the soil AM fungal community composition and strengthened the interaction between plants and AM fungi in this subtropical forest, while N addition could intensify the effects of warming on the plant-AM fungi system.

中文翻译：

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变暖对年轻亚热带杉木人工林土壤丛枝菌根真菌群落的影响大于施氮

摘要 变暖和氮 (N) 沉降是环境变化影响植物、微生物和土壤过程的两个重要方面。尽管丛枝菌根 (AM) 真菌在陆地生态系统中起着至关重要的作用，但变暖和 N 添加如何相互作用影响 AM 真菌群落仍然知之甚少。我们进行了为期 3 年的田间试验，以检查土壤变暖 (+5 ℃) 和 N（分别为 40、80 kg N ha−1 y−1，分别作为 LN 和 HN）对土壤 AM 真菌群落组成的影响在一个 4 年生的杉木种植园中。结果表明，无论 N 添加如何，变暖都会显着降低 AM 真菌多样性并改变 AM 真菌群落组成，而单独添加 N 的影响很小。更重要的是，加氮加氮处理对土壤AM真菌多样性和群落组成的变化大于单纯加温处理，表明加氮强化了加温对土壤AM真菌群落的影响。变暖改变了土壤 AM 真菌群落组成，随着球囊科的丰度减少，而双孢菌科、无孢子菌科、副球孢科和长孢菌科的丰度增加。此外，加温和加氮显着增加了根菌根的定植，加温加 HN 处理的增加最大。总之，我们的结果表明，变暖主要改变了土壤 AM 真菌群落组成，并加强了这片亚热带森林中植物和 AM 真菌之间的相互作用，