scholarly journals Spatial-Temporal Changes in Removal of Fecal Indicators and Diversity of Bacterial Communities in a Constructed Wetland with Ornamental Plants

2021 ◽  
Vol 11 (9) ◽  
pp. 3875
Author(s):  
Cristina S. C. Calheiros ◽  
Sofia I. A. Pereira ◽  
Albina R. Franco ◽  
Paula M. L. Castro

The present study was undertaken in a constructed wetland (CW), setup in a tourism house, for domestic wastewater treatment. The influence of season variations on the abundance of fecal indicator organisms (total coliforms and Escherichia coli) in the wastewater and in the substrate and the roots of plants inhabiting the inlet and outlet zones of the CW was evaluated along three consecutive years. The structure and diversity of bacterial communities associated to the CW’s substrate of inlet and outlet zones was also analyzed overtime. Wastewater was characterized for physicochemical and microbiological parameters and the bacterial communities colonizing the substrate surface, were analyzed by Denaturing Gradient Gel Electrophoresis (DGGE). The CW was effective in removing COD, BOD5, TSS, PO43−, NH4+, NO3−, and NO2−. It was also effective in removing fecal indicators, with a generalized decrease of total coliforms and E. coli in the substrate and in the wastewater from inlet to outlet of up to 2–3 log. The structure and composition of bacterial communities associated with the substrate was mainly influenced by the year rather than by the season or the CW zone.

Water ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1086
Author(s):  
Mario Licata ◽  
Roberto Ruggeri ◽  
Nicolò Iacuzzi ◽  
Giuseppe Virga ◽  
Davide Farruggia ◽  
...  

Dairy wastewater (DWW) contains large amounts of mineral and organic compounds, which can accumulate in soil and water causing serious environmental pollution. A constructed wetland (CW) is a sustainable technology for the treatment of DWW in small-medium sized farms. This paper reports a two-year study on the performance of a pilot-scale horizontal subsurface flow system for DWW treatment in Sicily (Italy). The CW system covered a total surface area of 100 m2 and treated approximately 6 m3 per day of wastewater produced by a small dairy farm, subsequent to biological treatment. Removal efficiency (RE) of the system was calculated. The biomass production of two emergent macrophytes was determined and the effect of plant growth on organic pollutant RE was recorded. All DWW parameters showed significant differences between inlet and outlet. For BOD5 and COD, RE values were 76.00% and 62.00%, respectively. RE for total nitrogen (50.70%) was lower than that of organic compounds. RE levels of microbiological parameters were found to be higher than 80.00%. Giant reed produced greater biomass than umbrella sedge. A seasonal variation in RE of organic pollutants was recorded due to plant growth rate Our findings highlight the efficient use of a CW system for DWW treatment in dairy-cattle farms.


2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
Qiufen Li ◽  
Yan Zhang ◽  
David Juck ◽  
Nathalie Fortin ◽  
Charles W. Greer

The impact of intensive land-based fish culture in Qingdao, China, on the bacterial communities in surrounding marine environment was analyzed. Culture-based studies showed that the highest counts of heterotrophic, ammonium-oxidizing, nitrifying, and nitrate-reducing bacteria were found in fish ponds and the effluent channel, with lower counts in the adjacent marine area and the lowest counts in the samples taken from 500 m off the effluent channel. Denaturing gradient gel electrophoresis (DGGE) analysis was used to assess total bacterial diversity. Fewer bands were observed from the samples taken from near the effluent channel compared with more distant sediment samples, suggesting that excess nutrients from the aquaculture facility may be reducing the diversity of bacterial communities in nearby sediments. Phylogenetic analysis of the sequenced DGGE bands indicated that the bacteria community of fish-culture-associated environments was mainly composed of Flavobacteriaceae, gamma- and deltaproteobacteria, including generaGelidibacter, Psychroserpen, Lacinutrix,andCroceimarina.


2011 ◽  
Vol 77 (19) ◽  
pp. 6972-6981 ◽  
Author(s):  
Ryan J. Newton ◽  
Jessica L. VandeWalle ◽  
Mark A. Borchardt ◽  
Marc H. Gorelick ◽  
Sandra L. McLellan

ABSTRACTThe complexity of fecal microbial communities and overlap among human and other animal sources have made it difficult to identify source-specific fecal indicator bacteria. However, the advent of next-generation sequencing technologies now provides increased sequencing power to resolve microbial community composition within and among environments. These data can be mined for information on source-specific phylotypes and/or assemblages of phylotypes (i.e., microbial signatures). We report the development of a new genetic marker for human fecal contamination identified through microbial pyrotag sequence analysis of the V6 region of the 16S rRNA gene. Sequence analysis of 37 sewage samples and comparison with database sequences revealed a human-associated phylotype within theLachnospiraceaefamily, which was closely related to the genusBlautia. This phylotype, termed Lachno2, was on average the second most abundant fecal bacterial phylotype in sewage influent samples from Milwaukee, WI. We developed a quantitative PCR (qPCR) assay for Lachno2 and used it along with the qPCR-based assays for humanBacteroidales(based on the HF183 genetic marker), totalBacteroidalesspp., and enterococci and the conventionalEscherichia coliand enterococci plate count assays to examine the prevalence of fecal and human fecal pollution in Milwaukee's harbor. Both the conventional fecal indicators and the human-associated indicators revealed chronic fecal pollution in the harbor, with significant increases following heavy rain events and combined sewer overflows. The two human-associated genetic marker abundances were tightly correlated in the harbor, a strong indication they target the same source (i.e., human sewage). Human adenoviruses were routinely detected under all conditions in the harbor, and the probability of their occurrence increased by 154% for every 10-fold increase in the human indicator concentration. Both Lachno2 and humanBacteroidalesincreased specificity to detect sewage compared to general indicators, and the relationship to a human pathogen group suggests that the use of these alternative indicators will improve assessments for human health risks in urban waters.


Author(s):  
Yakov Pachepsky ◽  
Matthew Stocker ◽  
Manuel Olmeda Saldaña ◽  
Daniel Shelton

2010 ◽  
Vol 8 (3) ◽  
pp. 231-237 ◽  
Author(s):  
Kaoru ABE ◽  
Akihito OOKUMA ◽  
Michio KOMADA ◽  
Sunao ITAHASHI ◽  
Kennji BANZAI

1983 ◽  
Vol 29 (10) ◽  
pp. 1261-1269 ◽  
Author(s):  
W. J. Robertson ◽  
R. S. Tobin

Fifteen stations, in two estuaries, along the Northumberland Strait of Nova Scotia were examined between June and September 1981 for a relationship between the concentrations of commonly monitored fecal indicator bacteria and the potential pathogens Candida albicans, Pseudomonas aeruginosa, and Vibrio parahaemolyticus. Increased densities of these three organisms were usually associated with high densities of indicator bacteria. Whereas C. albicans and P. aeruginosa occur in human fecal wastes, V. parahaemolyticus is indigenous to the marine environment and positively responds to elevated nutrient levels in sewage. There is also some evidence that these bacteria survive as long or longer in marine waters than the common indicator bacteria. While membrane-filtration techniques for the enumeration of C. albicans and P. aeruginosa proved satisfactory, a V. parahaemolyticus membrane-filtration method lacked specificity and was supplemented by a most-probable-number method. In marine recreational and shellfish waters, these three organisms could complement fecal coliforms and fecal streptococci as indicators of human fecal contamination.


2017 ◽  
pp. 157-176
Author(s):  
Mohd. Fadhil Md Din ◽  
Zaharah Ibrahim ◽  
Zaiton Abd Majid ◽  
Chi Kim Lim ◽  
Abdul Hadi Abdullah

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