| 摘要: |
| 浮游细菌在水库生态系统的物质循环中发挥着重要作用，并驱动着生物地球化学循环。本研究选取我国东南地区深水型水库——万安水库，以水温与溶解氧的垂直变化特征为依据，基于16S rRNA扩增子测序技术，对水库不同热分层时期浮游细菌群落组成、结构及其组装机制的变化进行研究。结果表明，热分层形成期浮游细菌α多样性在温跃层最高，滞水层最低；稳定期在滞水层较高，温跃层与混合层较低；消退期在温跃层与滞水层较高，混合层较低。分子生态网络分析表明，热分层消退期浮游细菌的正相关较高，模块化程度较低，网络关联更复杂。热分层形成期关键物种占比最高（30%），其次为消退期（24.38%）和稳定期（21.6%）。中性模型分别解释了形成期、稳定期、消退期79.7%、78.8%和64.1%的群落变化，细菌群落组装主要以随机性过程为主，同时环境因子也是影响浮游细菌群落组装的重要因素。三个热分层时期，浮游细菌群落主要受溶解氧、水温、叶绿素a、氮磷营养盐等的影响。本研究有助于水库的水质管理以及水生生态系统健康状况的评估。 |
| 关键词: 深水型水库 热分层 分子生态网络 群落构建 浮游细菌 |
| DOI： |
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| 基金项目:福建省水利科技项目（MSK202103, MSK202216）与福建省厦门环境监测中心站环保科技项目（2022S01） |
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| Spatiotemporal variation characteristics of bacterioplankton community structure and assembly patterns in a deep-water reservoir |
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Liu Huibo1, Fan Yifei1, Ruan Qizhen1, Dai Zetao1, Wang Feifei1, Yang Sheng Chang1, Xu Wenfeng2, Liu Lihua2, Cao Wenzhi1
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1.College of The Environment Ecology, Xiamen University;2.Fujian Xiamen Environmental Monitoring Central Station
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| Abstract: |
| Bacterioplankton play a crucial role in material cycling within reservoir ecosystems and drive biogeochemical cycles. This study selected Wan"an Reservoir, a deep-water reservoir in Southeastern China, based on the vertical variation characteristics of water temperature and dissolved oxygen and utilizing 16S rRNA gene amplicon sequencing technology, studied the variations in the composition, structure and assembly mechanism of bacterioplankton communities during different thermal stratification periods in the reservoir. The results indicate that during the formation of thermal stratification, the α-diversity of bacterioplankton was highest in the thermocline and lowest in the hypolimnion. During the stabilization period, α-diversity was higher in the hypolimnion and lower in both the thermocline and the mixed layer. In the recession period, α-diversity was elevated in both the thermocline and the hypolimnion, while it remained lower in the mixed layer. Molecular ecological network analysis indicates that during the recession periods of thermal stratification, there of positive correlation among bacterial lower level of modularity, and a more complex network association. During the period of thermal stratification formation, the proportion of key species was at its highest (30%), followed by the recession period (24.38%) and the stabilization period (21.6%). The neutral model explained 79.7%, 78.8%, and 64.1% of the community variations during the formation, stabilization, and recession periods, respectively. The assembly of bacterioplankton communities is primarily driven by stochastic processes; however, environmental factors also play a crucial role in influencing bacterioplankton community structure. Throughout the three periods of thermal stratification, the bacterioplankton community is mainly affected by dissolved oxygen, water temperature, chlorophyll a, nitrogen and phosphorus nutrients. This study aids in the management of water environment and ecological status in reservoirs and the assessment of the health of aquatic ecosystems. |
| Key words: Deep water reservoir Thermal stratification Molecular ecological network Community assembly Bacterioplankton |
