Bacterial community composition of an urban river in the North West Province, South Africa, in relation to physico-chemical water quality

• Published in: Environmental science and pollution research international 2016-03, Vol.23 (6), p.5868-5880
• Main Authors: Jordaan, K, Bezuidenhout, C. C
• Format: Article
• Language: English
• Subjects: Acidobacteria; Agriculture; anthropogenic activities; Anthropogenic factors; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Bacteria; bacterial communities; beta-Proteobacteria; Chemical analysis; Chemical oxygen demand; Chlorophyll; Community composition; community structure; Dissolved oxygen; Downstream; Earth and Environmental Science; Ecotoxicology; Effluents; Environment; Environmental Chemistry; Environmental conditions; Environmental Health; Environmental Monitoring; Environmental science; epsilon-Proteobacteria; Freshwater; Gold mines & mining; Heavy metals; microbiological quality; Multivariate analysis; Pesticides; plate count; Pollutants; Pollution; Research Article; Rice; Rivers; Rivers - chemistry; sequence analysis; Sewage treatment plants; South Africa; Studies; sulfates; temperature; Urban areas; Urbanization; Verrucomicrobia; Verrucomicrobium; Waste Water Technology; Water Management; Water Microbiology; Water Pollution; Water Pollution Control; Water Quality; Water supply; Water treatment
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-015-5786-7

The aim of this study was to determine the impacts of anthropogenic disturbances on bacterial community composition in an urban river (Mooi River). Physico-chemical analysis, bacterial enumeration and 454-pyrosequencing were conducted on the Mooi River system upstream and downstream of an urban settlement in the North West Province, South Africa. Pyrosequencing and multivariate analysis showed that nutrient inputs and faecal pollution strongly impacted the physico-chemical and microbiological quality at the downstream sites. Also, bacterial communities showed higher richness and evenness at the downstream sites. Multivariate analysis suggested that the abundances of Betaproteobacteria, Epsilonproteobacteria, Acidobacteria, Bacteroidetes and Verrucomicrobia are related to temperature, pH, dissolved oxygen (DO), sulphate and chlorophyll-a levels. These results suggest that urbanisation caused the overall water quality of this river to deteriorate, which in turn affected the bacterial community composition. In addition, our work identified potential indicator groups that may be used to track faecal and organic pollution in freshwater systems.