细菌群落组成对微囊藻水华分解过程的响应

The response of bacterial community composition to the decomposition of Microcystis blooms

为探究细菌群落组成对微囊藻水华腐败分解过程的响应,在太湖梅梁湾沿岸进行为期11 d的原位围隔实验,模拟蓝藻水华聚集分解过程,并监测了此过程中水体环境因子和细菌群落组成.结果表明,水体理化因子和细菌群落组成在微囊藻水华分解的过程中发生了显著变化.冗余分析显示细菌的群落组成与水体氧化还原环境(溶解氧或氧化还原电位)、pH值、浮游植物生物量和营养盐浓度(总磷、硝态氮浓度)密切相关.研究还发现了某些与微囊藻水华分解密切相关的特殊细菌类群,其中隶属于黄杆菌科(拟杆菌门)的一个类群在微囊藻厌氧分解的阶段占据显著优势,其功能有待于进一步研究.

To explore the response of bacterial community composition（ BCC） to the decomposition of Microcystis blooms,we conducted an eleven-day in situ enclosure experiment to simulate the aggregation and decomposition of cyanobacterial bloom near the shoreline of Meiliang Bay,Lake Taihu. The water quality parameters and the BCC in enclosures were monitored. The results showed that the physicochemical factors and the BCC significantly changed during course of the decomposition of Microcystis blooms. Redundancy analyses induated that the redox state of environment（ showed by dissolved oxygen or oxidation reduction potential）,p H,biomass of phytoplankton and nutrient elements（ total phosphorus and nitrate nitrogen） were closely related to the variation of the BCC. We also found that specific taxons in response to the decomposition of Microcystis blooms appeared in our experiment. A taxon,which affiliated to Flavobacterium（ Bacteroidetes）,significantly dominated during the period of anerobic decomposition of Microcystis blooms. The functions of the bacteria group need further exploration.