The majority of studies have found that an increase in tree species diversity can increase the productivity of forest stands thanks to complimentary effects with enhanced resource use efficiency or selection effects; however, it is unclear how tree species diversity affects the soil fungal community and enzyme activities in subtropical evergreen forests. In this study, we used soil high-throughput sequencing to investigate the soil fungal community structure and diversity in the central area of tree clusters in the gradient of tree species richness formed by four possible dominant tree species (Pinus massoniana Lamb., Choerospondias axillaris Roxb., Cyclobalanopsis glauca Thunb. and Lithocarpus glaber Thunb.) in subtropical evergreen broad-leaved forest. The results showed that soil organic carbon content and total nitrogen content were significantly higher in mixed tree clusters, and that soil fungal richness and diversity increased with the increase in tree species diversity (1–3 species). Soil acid phosphatase and urease activity were also enhanced with tree species diversity (p < 0.05). The relative abundance of soil symbiotic fungi (ectomycorrhizal fungi) decreased, while the relative abundance of saprotrophic fungi increased. Redundancy analysis (RDA) revealed that soil acid phosphatase activity was the main factor affecting soil fungal communities and functional guilds, and that soil water content was the main driving force behind fungal trophic modes. In subtropical forests, changes in tree species diversity have altered the soil fungal community structure and trophic modes and functions, accelerating the decomposition of organic matter, increasing nutrient cycling, and perhaps also changing the nutrient absorption of trees.

中文翻译：

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亚热带常绿林地方树种多样性梯度的土壤真菌群落及酶活性

大多数研究发现，树种多样性的增加可以提高林分的生产力，这要归功于资源利用效率提高或选择效应的互补效应；然而，目前尚不清楚树种多样性如何影响亚热带常绿林土壤真菌群落和酶活性。本研究利用土壤高通量测序技术，在四种可能优势树种（Pinus massoniana Lamb., Choerospondias axillaris Roxb. ., Cyclobalanopsis glauca Thunb. 和Lithocarpus glaberThunb.）在亚热带常绿阔叶林中。结果表明，混交树丛中土壤有机碳含量和全氮含量显着升高，土壤真菌丰富度和多样性随着树种多样性（1-3种）的增加而增加。土壤酸性磷酸酶和脲酶活性也随着树种多样性而增强（p < 0.05）。土壤共生真菌（外生菌根真菌）的相对丰度下降，而腐生真菌的相对丰度增加。冗余分析（RDA）表明，土壤酸性磷酸酶活性是影响土壤真菌群落和功能群的主要因素，土壤含水量是真菌营养模式的主要驱动力。在亚热带森林中，