Limnology/Department of Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
ISME J. 2010 Feb;4(2):171-81. doi: 10.1038/ismej.2009.108. Epub 2009 Oct 15.
Variation in traits causes bacterial populations to respond in contrasting ways to environmental drivers. Learning about this will help us understand the ecology of individual populations in complex ecosystems. We used 454 pyrosequencing of the hypervariable region V6 of the 16S rRNA gene to study seasonal dynamics in Baltic Sea bacterioplankton communities, and link community and population changes to biological and chemical factors. Surface samples were collected from May to October 2003 and in May 2004 at the Landsort Deep in the central Baltic Sea Proper. The analysis rendered, on average, 20 200 sequence reads for each of the eight samples analyzed, providing the first detailed description of Baltic Sea bacterial communities. Community composition varied dramatically over time, supporting the idea of strong temporal shifts in bacterioplankton assemblages, and clustered according to season (including two May samples from consecutive years), suggesting repeatable seasonal succession. Overall, community change was most highly correlated with change in phosphorus concentration and temperature. Individual bacterial populations were also identified that tightly co-varied with different Cyanobacteria populations. Comparing the abundance profiles of operational taxonomic units at different phylogenetic distances revealed a weak but significant negative correlation between abundance profile similarity and genetic distance, potentially reflecting habitat filtering of evolutionarily conserved functional traits in the studied bacterioplankton.
性状的变异导致细菌种群以不同的方式对环境驱动因素作出反应。了解这一点将有助于我们理解复杂生态系统中个体种群的生态学。我们使用 454 焦磷酸测序技术对 16S rRNA 基因的高变区 V6 进行了研究，以研究波罗的海浮游细菌群落的季节性动态，并将群落和种群变化与生物和化学因素联系起来。表层样品于 2003 年 5 月至 10 月和 2004 年 5 月在波罗的海中部的 Landsort 深海采集。对 8 个分析样本的平均分析结果为每个样本提供了 20,200 条序列读数，首次详细描述了波罗的海细菌群落。群落组成随时间剧烈变化，支持浮游细菌组合存在强烈的时间变化的观点，并根据季节聚类（包括连续两年的 5 月样本），表明可重复的季节性演替。总体而言，群落变化与磷浓度和温度的变化高度相关。还确定了与不同蓝藻种群紧密共变的个别细菌种群。比较不同系统发育距离的操作分类单位的丰度分布揭示了丰度分布相似性与遗传距离之间的弱但显著的负相关，这可能反映了所研究的浮游细菌中进化保守功能性状的栖息地过滤。
