Liu Lu, Wang Nan, Liu Min, Guo Zixiao, Shi Suhua
State Key Laboratory of Biocontrol, Guangdong Key Lab of Plant Resources, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), School of Life Sciences Sun Yat-Sen University Guangzhou China.
mLife. 2023 Mar 23;2(1):73-88. doi: 10.1002/mlf2.12060. eCollection 2023 Mar.
Bacterial communities play pivotal roles in nutrient cycling in mangrove forests. The assembly of mangrove microbial communities has been found to be influenced by complex factors, such as geographic distance, physicochemical conditions, and plant identity, but the relative importance of these factors and how these factors shape the assembling process remain elusive. We analyzed the bacterial communities sampled from three mangrove species (, , and ) at three locations along the estuarine Dongzhai Harbor in Hainan, China. We revealed larger differences in rhizosphere bacterial communities among geographical locations than among plant species, indicated by differences in diversity, composition, and interaction networks. We found that dispersal limitation and homogeneous selection have substantial contributions to the assembly of mangrove rhizosphere bacterial communities in all three locations. Following the phylogenetic-bin-based null model analysis (iCAMP) framework, we also found dispersal limitation and homogeneous selection showing dominance in some bins. The greater differences among geographic locations may be mainly attributed to the larger proportions of dispersal limitation even at such a short geographic distance. We also found that beta diversity was positively correlated with environmental distances, implying that the more similar environmental conditions (such as rich carbon and nitrogen contents) among plant species may have shaped similar bacterial communities. We concluded that the geographic distances, which are associated with dispersal limitation, played a key role in assembling mangrove rhizosphere bacterial communities, while physicochemical conditions and plant identity contributed less.
细菌群落对红树林的养分循环起着关键作用。人们发现红树林微生物群落的组装受到复杂因素的影响，如地理距离、理化条件和植物种类，但这些因素的相对重要性以及它们如何塑造组装过程仍不清楚。我们分析了从中国海南东寨港河口沿线三个地点的三种红树植物（、和）采集的细菌群落。我们发现，根际细菌群落在地理位置之间的差异大于植物种类之间的差异，这体现在多样性、组成和相互作用网络的差异上。我们发现，扩散限制和同质选择对所有三个地点的红树林根际细菌群落组装都有重大贡献。遵循基于系统发育箱的零模型分析（iCAMP）框架，我们还发现扩散限制和同质选择在某些箱中占主导地位。地理位置之间较大的差异可能主要归因于即使在如此短的地理距离内扩散限制的比例也更大。我们还发现，β多样性与环境距离呈正相关，这意味着植物种类之间更相似的环境条件（如丰富的碳和氮含量）可能塑造了相似的细菌群落。我们得出结论，与扩散限制相关的地理距离在红树林根际细菌群落组装中起关键作用，而理化条件和植物种类的贡献较小。
