Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China; School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China; Jiangxi Provincial Key Laboratory of Soil Erosion and Prevention, Jiangxi Institute of Soil and Water Conservation, Nanchang 330029, China.
Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China; School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China.
Sci Total Environ. 2016 Nov 1;569-570:382-389. doi: 10.1016/j.scitotenv.2016.06.130. Epub 2016 Jun 25.
Bacteria play a critical role in environmental and ecological processes in river ecosystems. We studied the bacterial community in the Ganjiang River, a major tributary of the Yangtze River, as it flowed through Nanchang, the largest city in the Ganjiang River basin. Water was sampled at five sites monthly during the wet season, and the bacterial community was characterized using Illumina high-throughput sequencing. A total of 811 operational taxonomic units (OTUs) were observed for all samples, ranging from 321 to 519 for each sample. The bacterial communities were maintained by a core of OTUs that persisted longitudinally and monthly. Actinobacteria (41.17% of total sequences) and Proteobacteria (31.80%) were the dominant phyla, while Firmicutes (mostly genus Lactococcus) became most abundant during flooding. Temperature and flow rate, rather than water chemistry, were the main factors influencing the bacterial community in river water. Temperature was the best individual parameter explaining the variations in OTU abundance, while flow rate was the best individual parameter explaining the variations in phylum abundance. Except for Proteobacteria, the relative abundance of bacterial phyla did not differ significantly between sites, and the degrees of influence of urban landscape on the bacterial community were estimated to be 17%-34%.
细菌在河流生态系统的环境和生态过程中起着关键作用。我们研究了赣江的细菌群落，赣江是长江的主要支流，流经赣江流域最大的城市南昌。在雨季，我们每月在五个地点采集水样，并使用 Illumina 高通量测序来描述细菌群落。所有样品共观察到 811 个操作分类单元（OTU），每个样品的范围为 321 到 519。细菌群落由纵向和逐月存在的核心 OTU 维持。放线菌（总序列的 41.17%）和变形菌（31.80%）是主要的门，而在洪水期间，厚壁菌门（主要是乳球菌属）变得最为丰富。温度和流速而不是水化学是影响河水细菌群落的主要因素。温度是解释 OTU 丰度变化的最佳单个参数，而流速是解释门丰度变化的最佳单个参数。除了变形菌门外，细菌门的相对丰度在不同地点之间没有显著差异，城市景观对细菌群落的影响程度估计为 17%-34%。
