Interactions Between Bacterioplankton Communities and Dissolved Substrates at the Bermuda Atlantic Time Series Study Station

利用浮游细菌核糖体RNA系统发育群特异性探针进行的杂交测量表明，在马尾藻海西北部的较低海洋表层，几个主要的浮游细菌群形成了高度分层的种群。同一地点的其他研究发现了一个季节性循环的证据，在春季期间，溶解有机碳(DOC)在上层积累，在冬季混合时被输出到下表层。本研究拟通过海水养殖实验，结合不同深度的水和接种物，研究浮游细菌群落组成与水体中DOC来源、数量和稳定性的关系。将使用扩增的核糖体RNA基因的高分辨率电泳图来调查群落组成。电泳图结果将通过将群落总RNA与特定于系统发育群的探针杂交来确认。这项研究的数据将与正在进行的浮游细菌产量、生物量和DOC的测量进行比较，这些测量是百慕大大西洋时间序列研究的一部分。

Hybridization measurements made with phylogenetic group-specific probes for bacterioplankton ribosomal RNAs have shown that several major bacterioplankton groups form highly stratified populations in the lower ocean surface layer in the northwestern Sargasso Sea. Other studies at the same site have uncovered evidence of a seasonal cycle in which dissolved organic carbon (DOC) accumulates in the upper surface layer during the vernal period and is exported to the lower surface layer during winter mixing. This study proposes to examine the relationship between the composition of bacterioplankton communities and the source, amount and lability of DOC in the water column by conducting seawater culture experiments that combine water and inocula from different depths. High-resolution electropherograms of amplified ribosomal RNA genes will be used to survey community composition. Electropherogram results will be confirmed by hybridizations of total community RNA to phylogenetic group-specific probes. Data from this study will be compared to ongoing measurements of bacterioplankton production, biomass and DOC that are a part of the Bermuda Atlantic Time-Series Study.