BACTERIAL COMMUNITY STRUCTURE AND ITS INFLUENCING FACTORS IN SURFACE SEDIMENTS OF THE NYANG RIVER IN THE DRY SEASON, CHINA

The Nyang River is located in an area sensitive to global climate change, the climate warming changes and human activities have impacted the fragile ecosystem of Plateau Rivers, for which we analyzed the bacterial diversity, community structure characteristics and main influencing factors in the surface sediments of 7 sampling sites in the middle and lower of the Nyang River in Tibet which is in China by high-throughput sequencing technology. The study showed that the abundance of bacterial community in the surface sediments of the middle and lower reaches of the Nyang River that is S1 (upstream of the junction of Bahe Town), S2 (Bahe River), S3 (downstream of the junction of Bahe Town), S4 (upstream of Duobu Hydropower Station), S5 (downstream of Duobu Hydropower Station), S6 (upstream of Bayi Town), S7 (downstream of Bayi Town). The abundance of bacterial community and bacterial diversity at S2 site are relatively high, and the bacterial diversity and abundance of the 7 sampling sites are lower than those of other areas. Five dominant bacteria phyla, including Firmicutes, L52.6, Tychonema_CCAP_1459-11B were extracted from the surface sediments of the middle and lower reaches of the Nyang River in the dry season. There were significant differences in the dominant bacteria among the samples. Further study found that the influencing factors were flow velocity, environmental factors and nutrients in descending order.