Yan Qingyun, Stegen James C, Yu Yuhe, Deng Ye, Li Xinghao, Wu Shu, Dai Lili, Zhang Xiang, Li Jinjin, Wang Chun, Ni Jiajia, Li Xuemei, Hu Hongjuan, Xiao Fanshu, Feng Weisong, Ning Daliang, He Zhili, Van Nostrand Joy D, Wu Liyou, Zhou Jizhong
Environmental Microbiome Research Center and the School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China.
Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China.
Mol Ecol. 2017 Jul;26(14):3839-3850. doi: 10.1111/mec.14151. Epub 2017 May 21.
Uncovering which environmental factors govern community diversity patterns and how ecological processes drive community turnover are key questions related to understand the community assembly. However, the ecological mechanisms regulating long-term variations of bacterioplankton communities in lake ecosystems remain poorly understood. Here we present nearly a decade-long study of bacterioplankton communities from the eutrophic Lake Donghu (Wuhan, China) using 16S rRNA gene amplicon sequencing with MiSeq platform. We found strong repeatable seasonal diversity patterns in terms of both common (detected in more than 50% samples) and dominant (relative abundance >1%) bacterial taxa turnover. Moreover, community composition tracked the seasonal temperature gradient, indicating that temperature is a key environmental factor controlling observed diversity patterns. Total phosphorus also contributed significantly to the seasonal shifts in bacterioplankton composition. However, any spatial pattern of bacterioplankton communities across the main lake areas within season was overwhelmed by their temporal variabilities. Phylogenetic analysis further indicated that 75%-82% of community turnover was governed by homogeneous selection due to consistent environmental conditions within seasons, suggesting that the microbial communities in Lake Donghu are mainly controlled by niche-based processes. Therefore, dominant niches available within seasons might be occupied by similar combinations of bacterial taxa with modest dispersal rates throughout different lake areas.
揭示哪些环境因素决定群落多样性模式以及生态过程如何驱动群落更替是与理解群落组装相关的关键问题。然而，湖泊生态系统中调节浮游细菌群落长期变化的生态机制仍知之甚少。在此，我们利用MiSeq平台的16S rRNA基因扩增子测序技术，对富营养化的东湖（中国武汉）浮游细菌群落进行了近十年的研究。我们发现，在常见（在超过50%的样本中检测到）和优势（相对丰度>1%）细菌类群的更替方面，存在强烈的、可重复的季节多样性模式。此外，群落组成跟踪了季节温度梯度，表明温度是控制观察到的多样性模式的关键环境因素。总磷也对浮游细菌组成的季节性变化有显著贡献。然而，季节内浮游细菌群落在主要湖区的任何空间模式都被其时间变异性所掩盖。系统发育分析进一步表明，由于季节内环境条件一致，75%-82%的群落更替受同质选择支配，这表明东湖中的微生物群落主要受基于生态位的过程控制。因此，季节内可用的优势生态位可能被不同湖区中具有适度扩散率的相似细菌类群组合所占据。
