盐湖开发对柴达木盆地盐湖湖水细菌的多样性影响

Influence of salt lake exploitation on the bacterial diversity of the salt lakes in the Qaidam Basin

我国西部的盐湖面临过度开发的危机,本文旨在了解盐田开发中对盐环境微生物的影响,并寻找可行的控制因素。应用PCR-DGGE法、普通PCR法和培养法联合测试了柴达木盆地的12个湖泊和察尔汗盐田、南霍布逊盐田的样品。研究发现盐田细菌属种比盐湖少50%以上,盐田菌群与盐湖相比已经发生明显变化。在同一水体但盐度存在差异的托素湖和大苏干湖不同位置取得样品的DGGE谱图有明显变化,证明了湖水特性——尤其是湖水的盐分浓度,对细菌种属的分布有较大影响。对同为硫酸镁亚型的盐湖和咸淡水湖的研究表明,在盐湖生态系统中,盐度和pH值是决定生物物种多样性的关键因素。研究认为盐度可以作为对盐湖菌群保护的重要指标之一,提出330g/L可以考虑作为硫酸镁亚型盐湖生态变化控制的参考临界值。

Salt lakes of west china are facing the crisis of over-exploitation.The purpose of this study were to understand the impacts of salt pans to microorganisms in the salt environment,and to find a feasible way for protection of the salt lakes.Bacterium species existing in 12 lakes of the Qaidam Basin and salt pans in Charhan and South Huobuxun were investigated by PCR,PCR-DGGE and bacterial culture.It was found that bacterial species in salt pans were more than 50% less than salt lake,and it had obviously changed.The DGGE results of different sits of the lakes(the Tuosu Lake and the Dasugan Lake)were also compared.It was showed that the characteristics of the lake water,particularly its salinity,have a large impact on the distribution of species of bacteria.By comparing the lakes wich has the same water type,magnesium sulfate subtypes,we suggested salinity and pH value might be the key factor on biological diversity,and 330g/L could be considered as critical values for control of ecological change of these kind of salt lakes.