Bacterial dynamics in the sub-surface constructed wetland

2001 ◽  
Vol 44 (11-12) ◽  
pp. 207-209 ◽  
Author(s):  
J. Vymazal ◽  
J. Balcarová ◽  
H. Doušová
Keyword(s):  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Flow Direction ◽  
Anaerobic Bacteria ◽  
Root Surface ◽  
Coliform Bacteria ◽  
Municipal Sewage ◽  
Limited Information ◽  
Bacterial Pollution ◽  
Steep Decrease

Constructed wetlands have been shown to be capable of removing a wide variety of contaminants, including bacterial pollution. However, only limited information exists on the distribution of bacteria on roots of macrophytes growing in constructed wetlands. Constructed wetland with sub-surface horizontal flow at Nucÿice near Prague, Czech Republic, was put in operation in 1996. The system treats municipal sewage from 650 PE and the total area of the beds, planted with Phalaris arundinacea and Phragmites australis in alternate stripes perpendicular to the flow direction, is 3,224 m2 (2 beds 62×26 m each). Pea gravel (8/16 mm) was used as a filtration material. During the period 1998-1999, distribution of total aerobic and anaerobic bacteria, coliform bacteria and fecal streptococci was monitored in wastewater as well as on roots of both macrophyte species. Counts of bacteria on root surface in the system at Nucÿice indicate that there is a steep decrease in bacterial numbers within the first few metres of the bed and that there is significantly more bacteria on roots of Phragmites as compared to Phalaris. There was no statistically significant influence of the season on the bacterial counts on roots of macrophytes.

Microbial characteristics of constructed wetlands

1997 ◽  
Vol 35 (5) ◽  
pp. 117-123 ◽  
Author(s):  
Vlasta Ottová ◽  
Jarmila Balcarová ◽  
Jan Vymazal
Keyword(s):  
Constructed Wetlands ◽  
Anaerobic Bacteria ◽  
Coliform Bacteria ◽  
Nitrifying Bacteria ◽  
The Czech Republic ◽  
Bacterial Pollution ◽  
Large Numbers ◽  
Microbial Characteristics ◽  
Conventional Systems ◽  
Aerobic And Anaerobic

Constructed wetlands have been shown to be capable of removing a wide variety of contaminants, including bacterial pollution. Wetlands are known to act as biofilters through a combination of physical, chemical and biological factors which all participate in the reduction of the number of bacteria. Five constructed wetlands in the Czech Republic were studied during 1994 and 1995 in order to determine removal of total and faecal coliform bacteria and Enterobacteriaceae. In addition, total count of aerobic and anaerobic bacteria were determined in water. Populations of nitrogen cycle bacteria were monitored on roots and rhizomes ofGlyceria maxima in the system at Doksy. The results revealed that the retention of coliform bacteria is very high and exceeds common retention values for conventional systems. The measurements also indicated that nitrifying bacteria were not present in wastewater, however, quite large numbers were found on the surface of roots and rhizomes of Glyceria. This fact can explain the significant nitrification observed in this system.

scholarly journals Prevalence of the stx2 Gene in Coliform Populations from Aquatic Environments

2004 ◽  
Vol 70 (6) ◽  
pp. 3535-3540 ◽  
Author(s):  
Cristina Garc�a-Aljaro ◽  
Maite Muniesa ◽  
Juan Jofre ◽  
Anicet R. Blanch
Keyword(s):  
Fecal Coliform ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Coliform Bacteria ◽  
Municipal Sewage ◽  
Aquatic Environments ◽  
Limited Information ◽  
Human Pathogens ◽  
E Coli

ABSTRACT Shiga toxin-producing Escherichia coli strains are human pathogens linked to hemorrhagic colitis and hemolytic uremic syndrome. The major virulence factors of these strains are Shiga toxins Stx1 and Stx2. The majority of the genes coding for these toxins are borne by bacteriophages. Free Stx2-encoding bacteriophages have been found in aquatic environments, but there is limited information about the lysogenic strains and bacteria present in the environment that are susceptible to phage infection. The aim of this work was to study the prevalence and the distribution of the stx 2 gene in coliform bacteria in sewage samples of different origins. The presence of the stx 2 gene was monitored every 2 weeks over a 1-year period in a municipal sewage treatment plant. A mean value of 102 genes/ml was observed without significant variation during the study period. This concentration was of the same order of magnitude in raw municipal sewage of various origins and in animal wastewater from several slaughterhouses. A total of 138 strains carrying the stx 2 gene were isolated by colony hybridization. This procedure detected approximately 1 gene-carrying colony per 1,000 fecal coliform colonies in municipal sewage and around 1 gene-carrying colony per 100 fecal coliform colonies in animal wastewaters. Most of the isolates belonged to E. coli serotypes other than E. coli O157, suggesting a low prevalence of strains of this serotype carrying the stx 2 gene in the wastewater studied.

Correlation Studies of Dissolved Oxygen in the IVCW System Changes and Removal of Nitrogen

2012 ◽  
Vol 610-613 ◽  
pp. 417-421
Author(s):  
Ji Ku Zhang ◽  
Yue Lang ◽  
Ming Jie Li
Keyword(s):  
Dissolved Oxygen ◽  
Constructed Wetlands ◽  
Total Nitrogen ◽  
Constructed Wetland ◽  
Flow Direction ◽  
Vertical Flow ◽  
Correlation Studies ◽  
Vertical Flow Constructed Wetlands ◽  
Vertical Flow Constructed Wetland ◽  
System Changes

Experiment simulates the integrated vertical flow constructed wetland (IVCW) operation of the system, discusses the trend of Dissolved Oxygen (DO) within the system and the relativity of DO and removing nitrogen. The results show that NH4+-N, NO3—-N and DO decrease along the flow direction in the integrated vertical flow constructed wetlands; NO3—-N increased and then decreased along the process; because of the DO of upstream pool is low, so the Total Nitrogen (TN) removing process occurs mainly in the downstream pool.

Biota participating in wastewater treatment in a horizontal flow constructed wetland

2001 ◽  
Vol 44 (11-12) ◽  
pp. 211-214 ◽  
Author(s):  
J. Vymazal ◽  
V. Sládeček ◽  
J. Stach
Keyword(s):  
Wastewater Treatment ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Horizontal Flow ◽  
Municipal Sewage ◽  
Wastewater Filtration ◽  
Oxygen Conditions ◽  
Cyanobacteria And Algae ◽  
Different Levels ◽  
Inflowing Water

During the period 1996-1997, three constructed wetlands with sub-surface horizontal flow were investigated. All systems are designed to treat municipal sewage from small villages (150, 200 and 300 PE). The survey included microscopical identification of organisms in both wastewater and filtration substrate. The organisms were used as an indication of oxygen conditions (aerobic, anoxic and anaerobic) in the particular microenvironment. Saprobiological terms characterizing different levels of saprobity were employed to characterize inflowing wastewater, filtration bed and outflowing water. The occurrence of organisms was correlated with BOD5 values in particular profiles. It has been found that the biocenosis in the inflowing wastewater differs from those found in the filtration bed and water outflowing from the vegetated beds. The organisms were grouped into those living under anaerobic and anoxic conditions and those living under aerobic conditions. More than 70 species of bacteria, amoebae, ciliates, rotifers, colorless flagellates, cyanobacteria and algae were found and the most important 45 species were figured in a plate together with saprobiological information for each species. Biota of the inflowing water is usually restricted to bacteria, ciliata and colorless flagellata while the organisms found in outflowing water as well as in periphyton growing on outflow structures indicate 2-3 levels better quality.

Applying Bacteriological Parameters for Evaluating Underground Water Quality

1988 ◽  
Vol 20 (11-12) ◽  
pp. 425-428 ◽  
Author(s):  
H. T. El-Zanfaly ◽  
A. M. Shabaan
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Samples ◽  
Anaerobic Bacteria ◽  
Underground Water ◽  
Faecal Coliforms ◽  
Bacterial Pollution ◽  
Important Approach ◽  
Positive Results ◽  
Faecal Streptococci

A total of 111 water samples were drawn from 15 wells. These samples were subjected to bacteriological examinations to determine the suitability of the monitored wells as source for drinking water. Significant levels of bacterial pollution indicators were detected in the underground water samples during the period of study. Total bacterial counts ranged between 10-104CFU/ml. Faecal streptococci was the most common and detected in 9 6% of water samples. Lower percentages of samples (92, 55 and 45%) were contaminated with total coliforms, faecal coliforms and total clostridia, respectively. Faecal coliforms: faecal streptococci was less than 0.7 in 86% of the examined samples. Anaerobic bacteria were detected in the examined well water samples. Only 101 water samples were tested for anaerobic spore-formers and all showed positive results. Most examined wells do not meet the water quality standards for drinking water. Accordingly, the necessity of controllin bacterial pollution in ground-water through disinfection was clearly confirmed. Testing the underground water for more than one indicator represents an important approach for water quality assurance.

Enhancement of nitrogen removal in subsurface flow constructed wetlands employing a 2-stage configuration, an unsaturated zone, and recirculation

1995 ◽  
Vol 32 (3) ◽  
pp. 59-67 ◽  
Author(s):  
Kevin D. White
Keyword(s):  
Constructed Wetlands ◽  
Nitrogen Removal ◽  
Constructed Wetland ◽  
Subsurface Flow ◽  
Great Promise ◽  
Effluent Recirculation ◽  
Wetland Treatment ◽  
Subsurface Flow Constructed Wetlands ◽  
Inlet Zone ◽  
Bod Removal

Constructed wetland technology is currently evolving into an acceptable, economically competitive alternative for many wastewater treatment applications. Although showing great promise for removing carbonaceous materials from wastewater, wetland systems have not been as successful at nitrification. This is primarily due to oxygen limitations. Nitrification does occur in conventional wetland treatment systems, but typically requires long hydraulic retention times. This paper describes a study that first evaluated the capability of subsurface flow constructed wetlands to treat a high strength seafood processor wastewater and then evaluated passive aeration configurations and effluent recirculation with respect to nitrogen treatment efficiency. The first stage of a 2-stage wetland treatment system exhibited a relatively short hydraulic retention time and was designed for BOD removal only. The second stage wetland employed an unsaturated inlet zone and effluent recirculation to enhance nitrification. Results indicate that organic loading, and thus BOD removal, in the first stage wetland is key to optimal nitrification. Passive aeration through an unsaturated inlet zone and recirculation achieved up to 65-70 per cent ammonia nitrogen removal at hydraulic retention times of about 3.5 days. Inlet zone configuration and effluent recirculation is shown to enhance the nitrogen removal capability of constructed wetland treatment systems.

scholarly journals Variation of Bacterial and Archaeal Community Structures in a Full-Scale Constructed Wetlands for Wastewater Treatment

Archaea ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Xiu-lu Lang ◽  
Xiang Chen ◽  
Ai-ling Xu ◽  
Zhi-wen Song ◽  
Xin Wang ◽  
...  
Keyword(s):  
Microbial Community ◽  
Constructed Wetlands ◽  
Relative Abundance ◽  
Constructed Wetland ◽  
Free Surface Flow ◽  
Archaeal Community ◽  
Illumina Miseq ◽  
Surface Flow ◽  
Community Structures ◽  
Soil And Water

Microorganisms play important roles in the reduction of organic and inorganic pollutants in constructed wetlands used for the treatment of wastewater. However, the diversity and structure of microbial community in constructed wetland system remain poorly known. In this study, the Illumina MiSeq Sequencing of 16S rDNA was used to analyze the bacterial and archaeal microbial community structures of soil and water in a free surface flow constructed wetland, and the differences of bacterial communities and archaeal compositions between soil and water were compared. The results showed that the Proteobacteria were the dominant bacteria, making up 35.38%~48.66% relative abundance. Euryarchaeotic were the absolute dominant archaea in the influent sample with the relative abundance of 93.29%, while Thaumarchaeota showed dominance in the other three samples, making up 50.58%~75.70%. The relative abundances of different species showed great changes in bacteria and archaea, and the number of dominant species in bacteria was much higher than that in archaea. Compared to archaea, the community compositions of bacteria were more abundant and the changes were more significant. Meanwhile, bacteria and archaea had large differences in compositions between water and soil. The microbial richness in water was significantly higher than that in soil. Simultaneously, soil had a significant enrichment effect on some microbial flora.

Enhancement of the performance of constructed wetlands for wastewater treatment in winter: the effect of Tubifex tubifex

RSC Advances ◽  
2016 ◽  
Vol 6 (41) ◽  
pp. 34841-34848 ◽  
Author(s):  
Yan Kang ◽  
Jian Zhang ◽  
Huijun Xie ◽  
Zizhang Guo ◽  
Pengfei Li ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Water Purification ◽  
Tubifex Tubifex ◽  
Batch Systems ◽  
Potential Use

An improved constructed wetland (CW) with the addition ofTubifex tubifexin winter was studied in laboratory batch systems. The outcomes of this study indicate that the potential use ofTubifex tubifexcould improve the ecosystem and water purification by CWs in winter.

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