生物多样性 ›› 2011, Vol. 19 ›› Issue (6): 770-778.DOI: 10.3724/SP.J.1003.2011.09149

所属专题: 中国的海洋生物多样性

• 论文 • 上一篇    下一篇

河口细菌群落多样性及其控制因素: 以切萨皮克湾为例

阚金军1*, 孙军2   

  1. 1Stroud Water Research Center, 970 Spencer Road, Avondale, PA 19311, USA
    2天津科技大学海洋科学与工程学院, 中国 天津 300457
  • 收稿日期:2011-08-24 修回日期:2011-11-30 出版日期:2011-11-20 发布日期:2011-12-19
  • 通讯作者: 阚金军
  • 基金资助:

    克里斯汀娜流域重点观测;浮游生物分类体系的完善及经典形态分类与新方法技术的比较与规范化探索;微食物环与生物地球化学循环的耦合作用

Bacterial community biodiversity in estuaries and its controlling factors: a case study in Chesapeake Bay

Jinjun Kan1*, Jun Sun2   

  1. 1 Stroud Water Research Center, 970 Spencer Road, Avondale, PA 19311, USA

    2 College of Marine Science and Engineering, Tianjin University of Science and Technology, Tianjin 300457, China
  • Received:2011-08-24 Revised:2011-11-30 Online:2011-11-20 Published:2011-12-19
  • Contact: Jinjun Kan
  • Supported by:

    Christina River Basin Critical Zone Observatory (CZO): Spatial and temporal integration of carbon and mineral fluxes: a whole watershed approach to quantifying anthropogenic modification of critical zone carbon sequestration (NSF 2010-2015)

摘要: 咸淡水的混合和重要营养盐与有机物的再循环, 使得河口成为地球上生产力较高而动态变化明显的水生生态系统。一个典型的河口区断面中, 细菌群落包含了一些从淡水到海洋的过渡类型: 例如α- 变形菌(Alphaproteobacteria)、β-变形菌(Betaproteobacteria)、γ-变形菌(Gammaproteobacteria)、蓝细菌(Cyanobacteria)[聚球藻(Synechococcus)]、拟杆菌(Bacteroidetes)、放线细菌(Actinobacteria)和疣微菌(Verrucomicrobia)等。此外, 河口也包含其独特的细菌群落: SAR11组、玫瑰杆菌属(Roseobacter)、SAR86和放线细菌(Actinobacteria)的一些进化亚枝(subclades), 表明海湾或者大型温带河口区细菌类群具有区域生态适应性。以研究较多的美国切萨皮克湾(Chesapeake Bay)为例, 其细菌群落呈现出显著的季节性变化和周期性的年际变化特征; 这些变化除了受水的滞留时间和细菌生长速度影响外, 还可能受其他许多环境因子的影响。其中叶绿素a和水温变化的影响最大, 其他环境因子如溶解氧、铵态氮、亚硝酸盐和硝酸盐以及病毒的丰度也有影响。近年来, 基于群落水平的基因组学(genomics)和后基因组学(postgenomics)(转录组学和蛋白质组学)技术应用于研究自然条件下微生物群落错综复杂的基因多样性和表达, 提供了揭示水环境中微生物群落组成和新功能基因的途径。

Abstract: Estuaries are among the most productive and dynamic aquatic ecosystems on earth, due to the mixing of fresh and salt waters and significant recycling of nutrients and organic matters. Sitting in a transitional zone, bacterial communities in an estuary typically harbor representatives of both freshwater and marine groups: Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Cyanobacteria (Synechococcus), Bacteroidetes, Actinobacteria, and Verrucomicrobia. In addition, estuaries such as Chesapeake Bay also contain their own unique bacterial signatures including the SAR11 group, Roseobacter, SAR86, and Actinobacteria subclades, suggesting the ecological adaptation of organisms endemic to the Bay or perhaps, to large temperate estuaries in general. Relative to spatial variations, remarkable seasonal shifts and recurring annual patterns were identified in Chesapeake Bay bacterial communities. Besides water residence time and bacterial growth rate, many other factors are potential driving forces for the microbial diversity and bacterial population dynamics we observed. Temporal variations in bacterial communities were best explained by change in chlorophyll a (Chl a) and water temperature, while other factors such as dissolved oxygen, ammonia, nitrite and nitrate, and viral abundance also appeared to contribute to seasonal succession. Recently, the applications applications of community-based genomics and postgenomics (transcriptomics and proteomics) have allowed us to study the comprehensive gene diversity and gene expression directly from natural microbial communities. We predict that further studies and analyses of these genes and proteins will deliver new discoveries regarding the composition and function of microbial communities in aquatic environments.