藻华爆发期太湖不同区域沉积物多样性

Bacterial Diversity of Sediment in Different Regions of Taihu Lake During the Algal Bloom

本研究以藻华爆发期的太湖不同区域沉积物为对象,测定氮、磷和生物量碳等理化性质,并通过末端限制性酶切片断长度多态性分析(T-RFLP)的分子生态学手段,鉴定不同富营养化湖区7个标准采样位点沉积物中细菌群落结构差异。结果表明,总氮、总磷含量以6#、16#样品最高,且各形态氮和各形态磷的趋势也与总氮、总磷趋势基本一致;生物量碳为6#和16#明显高于其他位点,其余各位点相近。T-RFLP结果显示,各位点细菌多样性间存在差异,其中16#样品的多样性指数最低,6#、7#和1#较高;在种群组成上各个位点无论是组分还是比例均有显著差异。另外,所取7个沉积物样品中与氮、磷循环相关的α、β和γ-变形菌纲含量非常丰富,且与硫、铁循环相关的δ-变形菌纲含量也很丰富。

In different regions of Taihu Lake, phosphorus, nitrogen and the microbial biomass C of the sediment were determined, and using the terminal restriction fragment length polymorphism （T-RFLP） technique, bacterial community structures were analyzed. The content of total nitrogen and total phosphorus of sediment No.6 and No. 16 were the highest. Trend of various forms of nitrogen and phosphorus with total nitrogen and total phosphorus was basically the same. The result of microbial biomass C showed that No.6 and No.16 were significantly higher than other sites which were similar with each other. Results of T-RFLP showed that there were differences between the bacterial diversity of different regions. Bacterial diversity of No. 16 was lowest, but No. 1, No.6 and No.7 were higher. Both the composition and the proportion of bacteria from different regions were significantly distinct. In addition, Alphaproteobacteria, Betaproteobacteria and Gammaproteobacteria which have relationship with cycle of nitrogen and phosphorus are very rich in sediment of all the sites. And Deltaproteobacteria which is related to cycle of sulfur and iron is also rich.