Microbial diversity in cold seep sediments from the northern South China Sea

详细信息	查看全文 | 推荐本文 |

• 作者：Yong Zhang^a ; ^b ; Xin Su^a ; ^b ; ^{xsu@cugb.edu.cn} ; Fang Chen^c ; Yuanyuan Wang^a ; ^b ; Lu Jiao^a ; ^b ; Hailiang Dong^a ; ^d ; Yongyang Huang^c ; Hongchen Jiang^a ; ^e ; ^{hongchen.jiang@gmail.com}
• 关键词：16S rRNA ; Microbial diversity ; Cold seep ; Marine sediments ; Northern South China Sea
• 刊名：Geoscience Frontiers
• 出版年：2012
• 期刊代码：pc98_16749871
• 类别：ear
• 出版时间：May, 2012
• 卷：3
• 期：3
• 页码：301-316
• 文件大小：1229 K

摘要

South China Sea (SCS) is the largest Western Pacific marginal sea. However, microbial studies have never been performed in the cold seep sediments in the SCS. In 2004, 鈥淪ONNE鈥?177 cruise found two cold seep areas with different water depth in the northern SCS. Haiyang 4 area, where the water depth is around 3000聽m, has already been confirmed for active seeping on the seafloor, such as microbial mats, authigenic carbonate crusts and bivalves. We investigated microbial abundance and diversity in a 5.55-m sediment core collected from this cold seep area. An integrated approach was employed including geochemistry and 16S rRNA gene phylogenetic analyses. Here, we show that microbial abundance and diversity along with geochemistry profiles of the sediment core revealed a coupled reaction between sulphate reduction and methane oxidation. Acridine orange direct count results showed that microbial abundance ranges from 10⁵ to 10⁶聽cells/g sediment (wet weight). The depth-related variation of the abundance showed the same trend as the methane concentration profile. Phylogenetic analysis indicated the presence of sulphate-reducing bacteria and anaerobic methane-oxidizing archaea. The diversity was much higher at the surface, but decreased sharply with depth in response to changes in the geochemical conditions of the sediments, such as methane, sulphate concentration and total organic carbon. Marine Benthic Group B, Chloroflexi and JS1 were predominant phylotypes of the archaeal and bacterial libraries, respectively.