A large amount of secondary successional vegetation (subtropical evergreen broadleaved forests) has formed after the extensive deforestation and cultivation of coniferous forests in Wuyi Mountain, Southeast China. However, we lack a detailed understanding of the dynamic changes in microbial community structure and its co‐occurrence network during succession. The features that are responsible for alterations in the soil bacterial community remain poorly defined. Therefore, we compared the soil physicochemical properties, enzyme activities, and bacterial diversity among three different forests (a coniferous forest [CF], early stage of succession; a mixed conifer‐broadleaf forest [CBMF], middle stage of succession; an evergreen broadleaf forest [EBF]; late stage of succession). Results indicated that the contents of soil organic carbon and microbial biomass carbon (MBC) in CBMF were higher compared with those in CF. The alpha diversity indices were the highest in CBMF. Functional annotation of prokaryotic taxa predicted the relative abundances of chemoheterotrophy and aerobic chemoheterotrophy were lower in CF than in the other two forests. Bacterial network topology was affected by forest succession, with CBMF having more complex bacterial networks. Mantel's test indicated the soil nitrate nitrogen content (P = 0.03) was the most important property that shaped the bacterial community composition, bacterial diversity was influenced by soil pH (P = 0.026), and the contents of available phosphorus (P = 0.04) and MBC (P = 0.022) during the succession process. In conclusion, the succession of secondary forests promoted soil nutrient accumulation and improved bacterial diversity and network complexity.

中文翻译：

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亚热带次生林演替的土壤细菌群落结构和共现网络

武夷山地区由于针叶林的大规模砍伐和开垦，形成了大量的次生演替植被（亚热带常绿阔叶林）。然而，我们对演替过程中微生物群落结构及其共现网络的动态变化缺乏详细的了解。导致土壤细菌群落变化的特征仍然不明确。因此，我们比较了三种不同森林（针叶林 [CF]，演替早期；针叶阔叶混交林 [CBMF]，演替中期；常绿阔叶林 [CBMF]，演替阶段）的土壤理化性质、酶活性和细菌多样性。森林[EBF]；演替后期）。结果表明，CBMF中的土壤有机碳和微生物量碳（MBC）含量高于CF中的土壤有机碳和微生物量碳（MBC）含量。 CBMF 中的 α 多样性指数最高。原核生物类群的功能注释预测，CF 中化能异养和需氧化能异养的相对丰度低于其他两个森林。细菌网络拓扑结构受到森林演替的影响，CBMF具有更复杂的细菌网络。 Mantel的测试表明土壤硝态氮含量（磷= 0.03）是影响细菌群落组成的最重要的特性，细菌多样性受到土壤 pH 值的影响（磷= 0.026），有效磷含量（磷= 0.04) 和 MBC (磷= 0.022) 在继承过程中。总之，次生林的演替促进了土壤养分积累，提高了细菌多样性和网络复杂性。