Bacterioplankton community shifts in an arctic lake correlate with seasonal changes in organic matter source
Bacterioplankton community shifts in an arctic lake correlate with seasonal changes in organic matter source
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DOI：
10.1128/aem.69.4.2253-2268.2003
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发表时间：
2003-04-01
影响因子：
4.4
通讯作者：
Hobbie, JE
中科院分区：
文献类型：
--
作者：
Crump, BC;Kling, GW;Hobbie, JE
浮游细菌群落组成的季节性变化在图利克湖，阿拉斯加北坡的苔原湖，有关的来源（陆地与浮游植物）和溶解有机物（DOM）的不稳定性的变化。16 S rRNA基因变性梯度凝胶电泳（DGGE）结果表明，春季季节性冰雪覆盖下的近地表沃茨中，在4 ℃时，群落组成发生了变化。这种转变与细菌生产力（[ C-14]亮氨酸掺入）的年度峰值相关，这是由与雪融水相关的不稳定陆地DOM的大量涌入所驱动的。第二个转变发生在初夏陆地DOM通量结束后，冰离开湖泊，浮游植物群落发展。浮游细菌群落由全年存在的持续种群和出现和消失的短暂种群组成。大部分的瞬时种群可以分为那些平流进入湖泊与陆地DOM在春季和那些在初夏的浮游植物群落的发展过程中，从低浓度增长。DGGE条带中的DNA测序表明，大多数条带代表单一的核糖体型，并且来自不同样品的匹配条带代表相同的核糖体型。细菌被鉴定为α-和β-变形菌门、噬细胞-黄菌门-拟杆菌门和放线菌门内全球分布的淡水系统发育簇的成员。
Seasonal shifts in bacterioplankton community composition in Toolik Lake, a tundra lake on the North Slope of Alaska, were related to shifts in the source (terrestrial versus phytoplankton) and lability of dissolved organic matter (DOM). A shift in community composition, measured by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA genes, occurred at 4degreesC in near-surface waters beneath seasonal ice and snow cover in spring. This shift was associated with an annual peak in bacterial productivity ([ C-14] leucine incorporation) driven by the large influx of labile terrestrial DOM associated with snow meltwater. A second shift occurred after the flux of terrestrial DOM had ended in early summer as ice left the lake and as the phytoplankton community developed. Bacterioplankton communities were composed of persistent populations present throughout the year and transient populations that appeared and disappeared. Most of the transient populations could be divided into those that were advected into the lake with terrestrial DOM in spring and those that grew up from low concentrations during the development of the phytoplankton community in early summer. Sequencing of DNA in DGGE bands demonstrated that most bands represented single ribotypes and that matching bands from different samples represented identical ribotypes. Bacteria were identified as members of globally distributed freshwater phylogenetic clusters within the alpha- and beta-Proteobacteria, the Cytophaga-Flavobacteria-Bacteroides group, and the Actinobacteria.