贵州阿哈湖沉积物中硫酸盐还原菌的时空分布特征

The vertical and temporal distributions of sulfate-reducing bacteria in sediments of Lake Aha

利用PCR扩增和荧光原位杂交方法对贵州阿哈湖沉积物中硫酸盐还原菌(Sulfate-reducing bacteria,SRB)类群和数量的时空分布特征进行了分析。结果表明,秋季沉积物中检测出四个SRB类群(脱硫肠菌属、脱硫叶菌属、脱硫球菌属—脱硫线菌属—脱硫八叠菌属和脱硫弧菌属—脱硫微菌属),而春季沉积物中只检测出三个类群(脱硫肠菌属、脱硫叶菌属和脱硫球菌属—脱硫线菌属—脱硫八叠菌属)。相比秋季,春季沉积环境溶解氧含量较高,且温度较低,这可能导致脱硫弧菌属—脱硫微菌属在春季沉积物中处于不可育状态,由于其活性低而无法检测。秋季沉积物检测出来的SRB类群相比春季沉积物具有更大的分布范围,同时,秋季沉积物SRB数量总体上高于春季沉积物,上述结果指示秋季沉积物环境条件更适于SRB群落。

The distribution of sulfate-reducing bacteria （SRB） in the sediments of Lake Aha was analyzed based on evaluation of the presence and quantity of six main groups of SRB in sediments collected during spring and au- tumn. The results show that four SRB groups （Desulfotomaculum, Desulfobulbus, Desulfococcus-Desulfonema-Desulfos- arcina and Desulfovibrio- Desulfomicrobium） are present in autumn, while only three groups （Desulfotomaculum, Desulfobulbus and Desulfococcus- Desulfonema-Desulfosarcina） are detected in spring. Compared with the autumn of Lake Aha, sediments in spring have relatively high dissolved oxygen contents and low temperature, which may lead to the inactive status of Desulfovibrio-Desulfomicrobium in the sediments and then the Desulfovibrio-Desulfomicrobium is undetectable due to its low activity. The distribution of each SRB group is wider in sediments collected in autumn than in spring, and they show a greater overall presence and quantity in autumn than in spring. These findings indi- cate that the environmental conditions in autumn are more suitable for SRBs.