Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing, 210098, PR China; College of Environmental Science and Engineering, Yangzhou University, Huayang West Road #196, Yangzhou, 225009, PR China.
Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Xikang Road #1, Nanjing, 210098, PR China.
J Environ Manage. 2019 Apr 1;235:368-376. doi: 10.1016/j.jenvman.2019.01.078. Epub 2019 Jan 30.
Black-odor phenomenon in highly urbanized river is increasingly recognized as a global ecological risk. Biotransformation associated with sulfur cycle is a major contributor to the blank-odor phenomenon. The vertical geochemical gradient in black-odor rivers is likely to alter microbial community assemblages and functions in the sulfur cycle. However, the interactions between geochemical gradients and microbial communities, as well as the changes in the process of sulfur biotransformation under different environmental conditions remain largely unknown. The vertical community assembly patterns and the impacts of microbial communities and genes on the biotransformation in the sulfur cycle were revealed in our study for the first time in a typical urban black-odor river, Jinchuan River, in China. Vertical beta-diversity patterns of microbial communities mainly resulted from species replacement that was largely driven by spatial turnover (β = 0.43) but also influenced by nestedness (β = 0.08). MiSeq sequencing and GeoChip 5.0 microarray chip approaches were applied and identify 41 bacterial genera, 8 archaeal genera, and 26 genes involved in the sulfur cycle in Jinchuan River. The vertical beta-diversity patterns of microbial profile mainly resulted from species replacement. Those sulfur-related bacterial and archaeal genera, accounting for 23.15% and 42.65% of the total bacteria and archaea respectively in analysed samples, were mainly responsible for sulfur reduction. According to redundancy analysis, oxidation-reduction potential (r = -0.8662, P < 0.05), S concentration (r = -0.6288, P < 0.05), and total nitrogen concentration (r = -0.6782, P < 0.05) were identified as factors that significantly affect sulfur-related microbial communities. The highest reaction potential was detected in the dissimilated sulfate reduction action and experienced an increase with depth increasing in the river system. The results indicated that the sulfur biotransformation in a deeper layer in river sediment could make more contribution to the black-odor phenomenon in urban rivers.
高度城市化河流中的黑臭现象日益被认为是一种全球性的生态风险。与硫循环有关的生物转化是黑臭现象的主要成因。黑臭河流中的垂直地球化学梯度很可能改变硫循环中的微生物群落组合和功能。然而，地球化学梯度和微生物群落之间的相互作用，以及在不同环境条件下硫生物转化过程的变化在很大程度上仍然未知。本研究首次揭示了中国典型城市黑臭河流——金川县中硫循环生物转化过程中垂直微生物群落组装模式及其对微生物群落和基因的影响。微生物群落的垂直β多样性模式主要归因于物种替代，这主要受空间周转率（β=0.43）驱动，但也受到嵌套性（β=0.08）的影响。MiSeq 测序和 GeoChip 5.0 微阵列芯片方法被应用于鉴定金川县中 41 个细菌属、8 个古菌属和 26 个参与硫循环的基因。微生物分布的垂直β多样性模式主要归因于物种替代。那些与硫有关的细菌和古菌属，分别占分析样本中总细菌和古菌的 23.15%和 42.65%，是硫还原的主要责任人。冗余分析表明，氧化还原电位（r=−0.8662，P<0.05）、S 浓度（r=−0.6288，P<0.05）和总氮浓度（r=−0.6782，P<0.05）是影响硫相关微生物群落的显著因素。在异化硫酸盐还原作用中检测到最高的反应潜力，并且随着河流系统深度的增加而增加。结果表明，河流沉积物较深部位的硫生物转化可能对城市河流的黑臭现象做出更大的贡献。
