Premium
Distribution and abundance of human‐specific Bacteroides and relation to traditional indicators in an urban tropical catchment
Author(s) -
Nshimyimana J. P.,
Ekklesia E.,
Shanahan P.,
Chua L. H. C.,
Thompson J. R.
Publication year - 2014
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/jam.12455
Subject(s) - sewage , upstream (networking) , watershed , water quality , biology , environmental science , ecology , environmental engineering , computer network , machine learning , computer science
Aims The study goals were to determine the relationship between faecal indicator bacteria ( FIB ), the HF 183 marker and land use, and the phylogenetic diversity of HF 183 marker sequences in a tropical urban watershed. Methods and Results Total coliforms, Escherichia coli, and HF 183 were quantified in 81 samples categorized as undeveloped, residential and horticultural from the Kranji Reservoir and Catchment in Singapore. Quantitative‐ PCR for HF 183 followed by analysis of variance indicated that horticultural areas had significantly higher geometric means for marker levels (4·3 × 10 4 HF 183‐ GE 100 ml −1 ) than nonhorticultural areas (3·07 × 10 3 HF 183‐ GE 100 ml −1 ). E. coli and HF 183 were moderately correlated in horticultural areas ( R = 0·59, P = 0·0077), but not elsewhere in the catchment. Initial upstream surveys of candidate sources revealed elevated HF 183 in a wastewater treatment effluent but not in aquaculture ponds. The HF 183 marker was cloned, sequenced and determined by phylogenetic analysis to match the original marker description. Conclusion We show that quantification of the HF 183 marker is a useful tool for mapping the spatial distribution and potential sources of human sewage contamination in tropical environments such as Singapore. Significance and Impact A major challenge for assessment of water quality in tropical environments is the natural occurrence and nonconservative behaviour of FIB . The HF 183 marker has been employed in temperate environments as an alternative indicator for human sewage contamination. Our study supports the use of the HF 183 marker as an indicator for human sewage in Singapore and motivates further work to determine HF 183 marker levels that correspond to public health risk in tropical environments.