洪水对大凌河河流浮游细菌群落的影响

洪水是一种突发性强、破坏力大的自然灾害,它不仅造成巨大的经济损失,而且对生态环境也有严重危害。在地球生物化学过程中起重要作用的微生物是否也受到影响值得深入研究。2012年采集了洪水暴发前后辽宁省锦州段大凌河表层水样,利用DGGE技术,结合PCA和RDA分析研究了洪水对河流表层水中细菌群落的影响。结果表明:(1)洪水发生前后河流表层水中的细菌群落发生了改变:洪水发生前河流中细菌群落结构与河段所处的自然环境有很大的相关性,而洪水发生后这一现象消失。(2)洪水发生前,影响细菌群落结构的主要环境因素是pH和盐度,而洪水发生后,影响细菌群落结构的主要环境因素是总磷。这一研究结果提示洪水通过改变河流表层水环境特性对其中的细菌群落进行重塑。

Effect of the flood on the bacterial community of bacteriaplankton in Daling River

The flood often causes damage to human and the environment. In order to determine whether the flood can affect the bacterial community which plays an important role in the process of geobiochemistry, we collected the surface water samples along Daling River before and after the flood in 2012. We analyzed the bacterial community of the samples using DGGE, combined with statistic methods PCA and RDA. The results were as follows: (1) The flood had a great effect on the bacterial community of bacteriaplankton in the river. Before the flood occured, the PCA result showed that samples formed clusters according to their natural habitat types, while this relationship disppeared after the flood. (2)The bacterial community was primely shaped by pH and salinity which was determined in other studies as well before the flood, while the main explanatory environmental factor was total phosphorus after the flood. Therefore,we came to a conclusion that the flood can shape the bacterial community by the shift of the environmental characteristic such as total phosphorus.