scholarly journals The Elliot Ditch Constructed Wetlands

2007 ◽  
Vol 2 (3) ◽  
pp. 79-87
Author(s):  
Aaron A Zambo
Keyword(s):  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Agricultural Runoff ◽  
Load Reduction ◽  
Nitrogen And Phosphorus ◽  
Detention Time ◽  
Wetland System ◽  
Contaminant Load

The purpose of this experiment was to determine the contaminant load reduction incurred using a constructed wetland with an average hydraulic detention time of five days in treating agricultural runoff. The main contaminants present in the runoff were nitrogen and phosphorus from agricultural fertilizers. The findings of the experiment show that significant contaminant load reduction results can be achieved with a detention time, of as little as five days, in a properly constructed wetland system.

scholarly journals The Use of Constructed Wetland for Mitigating Nitrogen and Phosphorus from Agricultural Runoff: A Review

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 476
Author(s):  
Jiayu Li ◽  
Bohong Zheng ◽  
Xiao Chen ◽  
Zhe Li ◽  
Qi Xia ◽  
...  
Keyword(s):  
Plant Species ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Lemna Minor ◽  
Hydrilla Verticillata ◽  
Agricultural Runoff ◽  
Structure Design ◽  
Ceratophyllum Demersum ◽  
Nitrogen And Phosphorus ◽  
Emergent Plants

The loss of nitrogen and phosphate fertilizers in agricultural runoff is a global environmental problem, attracting worldwide attention. In the last decades, the constructed wetland has been increasingly used for mitigating the loss of nitrogen and phosphate from agricultural runoff, while the substrate, plants, and wetland structure design remain far from clearly understood. In this paper, the optimum substrates and plant species were identified by reviewing their treatment capacity from the related studies. Specifically, the top three suitable substrates are gravel, zeolite, and slag. In terms of the plant species, emergent plants are the most widely used in the constructed wetlands. Eleocharis dulcis, Typha orientalis, and Scirpus validus are the top three optimum emergent plant species. Submerged plants (Hydrilla verticillata, Ceratophyllum demersum, and Vallisneria natans), free-floating plants (Eichhornia crassipes and Lemna minor), and floating-leaved plants (Nymphaea tetragona and Trapa bispinosa) are also promoted. Moreover, the site selection methods for constructed wetland were put forward. Because the existing research results have not reached an agreement on the controversial issue, more studies are still needed to draw a clear conclusion of effective structure design of constructed wetlands. This review has provided some recommendations for substrate, plant species, and site selections for the constructed wetlands to reduce nutrients from agricultural runoff.

Constructed wetland for water quality improvement: a case study from Taiwan

2010 ◽  
Vol 62 (10) ◽  
pp. 2408-2418 ◽  
Author(s):  
C. Y. Wu ◽  
J. K. Liu ◽  
S. H. Cheng ◽  
D. E. Surampalli ◽  
C. W. Chen ◽  
...  
Keyword(s):  
Water Quality ◽  
Wastewater Treatment ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Water Reuse ◽  
Oxygen Demand ◽  
Sediment Oxygen Demand ◽  
Nucleotide Sequence Analysis ◽  
Sediment Samples ◽  
Wetland System

In Taiwan, more than 20% of the major rivers are mildly to heavily polluted by domestic, industrial, and agricultural wastewaters due to the low percentage of sewers connected to wastewater treatment plants. Thus, constructed or engineered wetlands have been adopted as the major alternatives to clean up polluted rivers. Constructed wetlands are also applied as the tertiary wastewater treatment systems for the wastewater polishment to meet water reuse standards with lower operational costs. The studied Kaoping River Rail Bridge Constructed Wetland (KRRBCW) is the largest constructed wetland in Taiwan. It is a multi-function wetland and is used for polluted creek water purification and secondary wastewater polishment before it is discharged into the Kaoping River. Although constructed wetlands are feasible for contaminated water treatment, wetland sediments are usually the sinks for organics and metals. In this study, water and sediment samples were collected from the major wetland basins in KRRBCW. The investigation results show that more than 97% of total coliforms (TC), 55% of biochemical oxygen demand (BOD), and 30% of nutrients [e.g. total nitrogen (TN), total phosphorus (TP)] were removed via the constructed wetland system. However, results from the sediment analyses show that wetland sediments contained high concentrations of metals (e.g. Cu, Fe, Zn, Cr, and Mn), organic contents (sediment oxygen demand = 1.7 to 7.6 g O2/m2 d), and nutrients (up to 18.7 g/kg of TN and 1.22 g/kg of TN). Thus, sediments should be excavated periodically to prevent the release the pollutants into the wetland system and causing the deterioration of wetland water quality. Results of polymerase chain reaction (PCR), denaturing gradient gel electrophoresis (DGGE), and nucleotide sequence analysis reveal that a variation in microbial diversity in the wetland systems was observed. Results from the DGGE analysis indicate that all sediment samples contained significant amounts of microbial ribospecies, which might contribute to the carbon degradation and nitrogen removal. Gradual disappearance of E. coli was also observed along the flow courses through natural attenuation mechanisms.

scholarly journals PARAMETERS EVALUATION OF MUNICIPAL WASTE WATER AFTER TREATMENT USING SUB SURFACE FLOW CONSTRUCTED WETLAND IN EKANT PARK BHOPAL

2016 ◽  
Vol 4 (12) ◽  
pp. 24-30
Author(s):  
Shalini Saxena
Keyword(s):  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Suspended Solids ◽  
Removal Rate ◽  
Surface Flow ◽  
Chemical Parameters ◽  
Nitrogen And Phosphorus ◽  
Public Park ◽  
Physico Chemical ◽  
Natural Wetlands

Land areas which are wet during part or all of the year are referred as wetlands. Constructed wetlands are manmade systems that mimic the functions of natural wetlands and applied for wastewater treatment. Aim of the present study is to investigate the feasibility of using a Tracheophyte, Phragmiteskarka in constructed wetland for treatment of wastewater in an public park. The daily inlet and outlet wastewater physico-chemical parameters were analysed during the period of two months. The parameters studied were pH, BOD, COD, DO, Total Suspended Solids, Total Dissolved Solids, Nitrogen and Phosphorus. The percentage removal of the parameters were analysed and studied until the percent removal rate gets stabilized. The study showed that the subsurface flow constructed wetlands are best alternative among modern treatments.

scholarly journals Wetland Technologies for Nursery and Greenhouse Compliance with Nutrient Regulations

HortScience ◽  
2013 ◽  
Vol 48 (9) ◽  
pp. 1103-1108 ◽  
Author(s):  
Sarah A. White
Keyword(s):  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Public Awareness ◽  
Subsurface Flow ◽  
Agricultural Runoff ◽  
Surface Flow ◽  
Treatment Wetlands ◽  
Treatment Technology ◽  
Subsurface Flow Constructed Wetlands ◽  
Floating Treatment Wetlands

The need to protect our water resources and increasing public awareness of the importance of cleaner water for ecological and human health reasons are driving regulations limiting nutrient release from traditionally exempt, non-point source agricultural contributors. Modification of production practices alone may not be adequate to meet regulated nutrient criterion limits for irrigation and stormwater runoff entering surface waters. Three constructed wetland technologies are well suited to help agricultural producers meet current and future regulations. The first two technologies, surface- and subsurface-flow constructed wetlands, have been in use for over 40 years to cleanse various types of wastewater, whereas floating treatment wetlands are an emerging remediation technology with potential for both stormwater and agricultural runoff treatment applications. The mechanisms driving removal of both nitrogen (N) and phosphorus (P) in constructed wetland systems are discussed. Surface-flow constructed wetlands remediate N contaminants from both container nursery and greenhouse production wastewater, whereas P remediation is variable and tied most closely to active plant growth as the constructed wetland ages. Subsurface-flow constructed wetlands effectively remediate N from production wastewater and can be tailored to increase consistency of P remediation through selection of P-sorbing root-bed substrates. Floating treatment wetlands effectively remediate both N and P with a designed surface area of a pond covered depending on the target effluent concentration or regulated total maximum daily load. The choice of treatment technology applied by growers to meet regulated water quality targets should be based on both economic and site-specific considerations.

Nutrient Removal from Polluted River Water by Using Vertical and Horizontal Subsurface Flow Constructed Wetlands

2011 ◽  
Vol 393-395 ◽  
pp. 1304-1307 ◽  
Author(s):  
En Shi ◽  
Zong Lian She ◽  
Tian Xie ◽  
Jian Wu ◽  
Xiao Hui Fu
Keyword(s):  
River Water ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Nutrient Removal ◽  
Subsurface Flow ◽  
Vertical Flow ◽  
Experiment Research ◽  
Nitrogen And Phosphorus ◽  
Polluted River ◽  
Subsurface Flow Constructed Wetland

The main purpose of this study was to treat organic pollutants, nitrogen and phosphorus in polluted river water by the use of constructed wetland (CW) systems. A laboratory experiment research was conducted on subsurface flow constructed wetland systems operated in vertical flow (VF) and horizontal flow (HF) mode. The systems were unplanted and hydraulic retention times were identically 2.7 days. The average removal efficiencies for HFCW and VFCW were NH+ 4-N 64.9% and 75.2%, NO- 3-N 92.3% and 40.1%, COD 97.5% and 90.1%, TP 94.6% and 96.2%, respectively. The removal of NH+ 4-N and NO- 3-N in the different CW units were in order of VFCW (drained) > VFCW (flooded) > HFCW and HFCW > VFCW (flooded) > VFCW (drained), respectively. When the water level in the VFCW was changed, an obvious fluctuation of the effluent NH+ 4-N and NO- 3-N concentrations was observed.

Using a constructed wetland for non-point source pollution control and river water quality purification: a case study in Taiwan

2010 ◽  
Vol 61 (10) ◽  
pp. 2549-2555 ◽  
Author(s):  
C. Y. Wu ◽  
C. M. Kao ◽  
C. E. Lin ◽  
C. W. Chen ◽  
Y. C. Lai
Keyword(s):  
Water Quality ◽  
Wastewater Treatment ◽  
Quality Improvement ◽  
Point Source ◽  
River Water ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
River Water Quality ◽  
Water Quality Improvement ◽  
Wetland System

The Kaoping River Rail Bridge Constructed Wetland, which was commissioned in 2004, is one of the largest constructed wetlands in Taiwan. This multi-function wetland has been designed for the purposes of non-point source (NPS) pollutant removal, wastewater treatment, wildlife habitat, recreation, and education. The major influents of this wetland came from the local drainage trench containing domestic, agricultural, and industrial wastewaters, and effluents from the wastewater treatment plant of a paper mill. Based on the quarterly investigation results from 2007 to 2009, more than 96% of total coliforms (TC), 48% of biochemical oxygen demand (BOD), and 40% of nutrients (e.g. total nitrogen, total phosphorus) were removed via the constructed wetland system. Thus, the wetland system has a significant effect on water quality improvement and is capable of removing most of the pollutants from the local drainage system before they are discharged into the downgradient water body. Other accomplishments of this constructed wetland system include the following: providing more green areas along the riversides, offering more water assessable eco-ponds and eco-gardens for the public, and rehabilitating the natural ecosystem. The Kaoping River Rail Bridge Constructed Wetland has become one of the most successful multi-function constructed wetlands in Taiwan. The experience obtained from this study will be helpful in designing similar natural treatment systems for river water quality improvement and wastewater treatment.

scholarly journals Removal of nitrogen and phosphorus from cattle farming wastewater using constructed wetland system

2016 ◽  
Vol 11 (44) ◽  
pp. 4542-4550 ◽  
Author(s):  
P. GUIMARAES Geovana ◽  
G. ALVES Dinara ◽  
F. JORGE Marcos ◽  
L. NASCENTES Alexandre ◽  
F. de PINHO Camila ◽  
...  
Keyword(s):  
Constructed Wetland ◽  
Nitrogen And Phosphorus ◽  
Wetland System ◽  
Cattle Farming

scholarly journals Integrating MFT-qPCR techniques in constructed wetland faecal bacterial purification monitoring; a case of a typical tropical hybrid constructed wetland system

2018 ◽  
Vol 78 (9) ◽  
pp. 2008-2018 ◽  
Author(s):  
Donde Oscar Omondi ◽  
Muia Anastasia Wairimu ◽  
Makindi Stanley Maingi ◽  
Onyango Godfrey Otieno ◽  
Kibet Caroline Jepkorir ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Constructed Wetlands ◽  
Constructed Wetland ◽  
Membrane Filtration ◽  
Pathogenic Bacteria ◽  
Quantitative Polymerase Chain Reaction ◽  
Health Concern ◽  
Human Pathogens ◽  
Purification Efficiency ◽  
Wetland System

Abstract The sanitation control of pathogens in the tropical effluents needs much more attention to ensure ecosystem health integrity and the safety of human health. The common use of chemicals in achieving this in wastewater treatment has remained unsustainable due to much health concern. Indeed, based on the numerous challenges associated with faecal pathogenic bacteria in wastewaters, the focus is now on achieving higher purification efficiencies in the elimination of the human pathogens from wastewater through eco-sustainable systems such as constructed wetlands (CWs). Hence, the need to explore the application of constructed wetlands in wastewater treatment under specific local environmental conditions for accurate understanding and improved treatment efficiency. This study therefore aimed at monitoring constructed wetlands faecal bacteria purification efficiency through integrated non-molecular membrane filtration technique and molecular quantitative polymerase chain reaction (MFT-qPCR) technique. The results showed some shortfall in the treatment system and also proved that integrating MFT-qPCR in faecal bacterial purification monitoring within a constructed wetland system provides a more accurate and reliable outcome. Additionally, the wetland purification efficiency was low (<80%) with the dissolved oxygen posing the strongest influence on faecal pathogenic bacterial purification trend across the wetland. Hence, the need to regularly carry out dredging and macrophyte harvesting as well as the use of holistic and more integrative approaches such as MFT-qPCR in managing and monitoring the performance of CWs in faecal pathogen eradication for improved CWs purification efficiency.

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