Key Laboratory of Marine Ecosystem Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, 36 Baochubei Road, Hangzhou 310012, PR China; Observation and Research Station of Yangtze River Delta Marine Ecosystems, Ministry of Natural Resources, 99 South Haida Road, Zhoushan 316053, PR China.
State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, 36 Baochubei Road, Hangzhou 310012, PR China; Observation and Research Station of Yangtze River Delta Marine Ecosystems, Ministry of Natural Resources, 99 South Haida Road, Zhoushan 316053, PR China.
Sci Total Environ. 2024 Nov 15;951:175755. doi: 10.1016/j.scitotenv.2024.175755. Epub 2024 Aug 23.
Disentangling microbial community diversity patterns and assembly mechanisms is critical for understanding ecological processes and evaluating biogeochemical cycling in ecosystems. However, the diversity patterns and assembly mechanism of the microbial communities in the epipelagic waters in the northeastern Indian Ocean (NEIO) on the spatial scale are still unclear. In this study, we investigated the spatial dynamics, geographic distribution pattern, and assembly process of the bacterial community using 532 samples collected from the epipelagic waters in the NEIO during the northeast monsoon. The results indicate that the bacterial richness and Bray-Curtis dissimilarity exhibited the strongest correlations with depth compared to the latitudinal and longitudinal scales. The dissolved oxygen was identified as the most important environmental factor affecting the bacterial richness and Bray-Curtis dissimilarity compared to temperature and salinity. The distance-decay relationship (DDR) of the bacterial community strengthened with increasing water depth. Turnover was the predominant β-diversity component influencing the spatial changes in the whole bacterial community. The dispersal limitation of the stochastic process and homogeneous selection of the deterministic process governed the bacterial ecological assembly process of the whole bacterial community. Abundant and rare subcommunities differed in terms of the niche breath, composition changes. The abundant subcommunities exhibited a much wider niche breath than the rare subcommunities. Regarding the abundant subcommunity species changes, the contributions of the turnover and nestedness varied with the water depth and oceanic region. In contrast, turnover was the major β-diversity component regarding the changes in the rare species. These data improve our understanding of the ecological processes of bacterial community assemblages in the NEIO.
解析微生物群落多样性模式和组装机制对于理解生态过程和评估生态系统中的生物地球化学循环至关重要。然而，东北印度洋（NEIO）表水层微生物群落的多样性模式和组装机制在空间尺度上仍不清楚。在这项研究中，我们利用东北季风期间在 NEIO 表水层采集的 532 个样本，研究了细菌群落的空间动态、地理分布模式和组装过程。结果表明，与纬度和经度尺度相比，细菌丰富度和 Bray-Curtis 不相似性与深度的相关性最强。与温度和盐度相比，溶解氧被确定为影响细菌丰富度和 Bray-Curtis 不相似性的最重要环境因素。细菌群落的距离衰减关系（DDR）随水深的增加而增强。周转率是影响整个细菌群落空间变化的主要β多样性组成部分。随机过程的扩散限制和确定性过程的均匀选择控制了整个细菌群落的细菌生态组装过程。丰富和稀有亚群落在生态位宽度、组成变化方面存在差异。丰富亚群落的生态位宽度比稀有亚群落宽得多。关于丰富亚群物种变化，周转率和嵌套性的贡献随水深和海洋区域而变化。相比之下，关于稀有物种的变化，周转率是主要的β多样性组成部分。这些数据提高了我们对 NEIO 中细菌群落组装生态过程的理解。
