Non-point source pesticide removal by a mountainous wetland

2002 ◽  
Vol 46 (6-7) ◽  
pp. 199-206 ◽  
Author(s):  
C.M. Kao ◽  
J.Y. Wang ◽  
K.F. Chen ◽  
H.Y. Lee ◽  
M.J. Wu

Non-point source (NPS) pollution is believed to be one of the major causes of impairment of water bodies. Among NPS pollution, agricultural NPS pollution is considered to be the largest single category resulting in water quality deterioration. Pesticides are some the most ubiquitous of these agricultural NPS pollutants. In this study, a mountainous wetland was selected to investigate the effects of the natural wetland system on the NPS pesticide (atrazine) removal to maintain the surface water quality. The selected wetland receives water from two unnamed creeks, which drain primarily upgradient agricultural lands. Wetland investigation and monitoring were conducted from November 1999 to March 2001. Major storm events and baseline water quality samples were analyzed. Field results indicate that the wetland was able to remove NPS atrazine flushed from the upgradient agricultural lands after the occurrence of storm events. Laboratory aerobic and anaerobic bioreactor experiments were conducted to evaluate the biodegradation of atrazine under the intrinsic conditions of the wetland system. Microbial enumeration was conducted for a quick screen of bacterial activity in the studied wetland. Results from the study suggest that the methanogenesis process was possibly the dominant biodegradation pattern, and atrazine can be degraded under reductive dechlorinating conditions when sufficient intrinsic organic matter was provided. Results from this study can provide us with further knowledge on pesticide removal mechanisms in natural wetlands and evaluate the role of wetlands in controlling pesticide pollutants from stormwater runoff.

2012 ◽  
Vol 47 (3) ◽  
pp. 279-286
Author(s):  
H Momtaz ◽  
F Alam ◽  
MA Ahsan ◽  
MA Akbor ◽  
MM Rashid

Some important physico-chemical properties of surface water around DEPZ industrial area, Savar were studied to evaluate the water quality. Seven water samples were collected from major waterbodies of DEPZ industrial area. The value of Physico-chemical parameter such as Temperature (57-24°C), pH (12.45-7.58), EC (12400-2060 ?s/cm), BOD5 (895-63.19 mg/L), TSS (2170-435 mg/L), TDS (6840-1036 mg/L), Turbidity (89.55-32.16 mg/L) and Salinity (7.1-1.0 ppt) were highest in the point source (W1) and began to decline as the waste dispersed through the nearby waterbodies (W2-W7). The result revealed that all the chemical constituents, except a few, were beyond the recommended limit for various uses. The lowest content of DO (0.10 mg/L) and highest content of BOD5 (895 mg/L) in point source waterbody indicate that the industries were releasing large amount of oxygen demanding organic wastes which subsequently affected all the studied waterbody. Among metal content of the study area, the value of Fe (1.331-0.443 mg/L), Zn (0.308-0.134 mg/L), Cu (0.244 0.127 mg/L) and Cr (0.615-0.055 mg/L) were gradually decreased from point source to the remote area. Point source (W1) waterbody had the highest concentration of Cr (0.615 mg/L) which exceeded the safe limit for industrial wastewater. This may be due to various chrome agent used in dyeing purposes. Anionic parameters like F- and PO4 3- were at intolerable limit in some waterbody. The coefficient of correlation analysis among physicochemical properties indicated that all the parameters had significant contribution to pollute the water. The correlation between DO and pH was strongly negative (r=-0.995**). Fe showed positive significant correlation with Zn, Cu and Cr. There was a significant positive interaction of PO4 3- with Cl- and NO3- in case of water quality deterioration. The above findings showed that the surface water around DEPZ industrial area was highly polluted by the industrial activities and was harmful for life. DOI: http://dx.doi.org/10.3329/bjsir.v47i3.13061 Bangladesh J. Sci. Ind. Res. 47(3), 279-286, 2012


2001 ◽  
Vol 44 (11-12) ◽  
pp. 585-590 ◽  
Author(s):  
C.M. Kao ◽  
J.Y. Wang ◽  
H.Y. Lee ◽  
C.K. Wen

In Taiwan, non-point source (NPS) pollution is one of the major causes of impairment of surface waters. The main objective of this study was to evaluate the efficacy of using constructed wetlands on NPS pollutant removal and water quality improvements. A field-scale constructed wetland system was built inside the campus of National Sun Yat-Sen University (located in southern Taiwan) to remove (1) NPS pollutants due to the stormwater runoff, and (2) part of the untreated wastewater from school drains. The constructed wetland was 40 m (L) × 30 m (W) × 1 m (D), which received approximately 85 m3 per day of untreated wastewater from school drainage pipes. The plants grown on the wetland included floating (Pistia stratiotes L.) and emergent (Phragmites communis L.) species. One major storm event and baseline water quality samples were analyzed during the monitoring period. Analytical results indicate that the constructed wetland removed a significant amount of NPS pollutants and wastewater constituents. More than 88% of nitrogen, 81% of chemical oxygen demand (COD), 85% of heavy metals, and 60% of the total suspended solids (TSS) caused by the storm runoff were removed by the wetland system before discharging. Results from this study may be applied to the design of constructed wetlands for NPS pollution control and water quality improvement.


2001 ◽  
Vol 44 (11-12) ◽  
pp. 539-544 ◽  
Author(s):  
C.M. Kao ◽  
J.Y. Wang ◽  
M.J. Wu

Agricultural non-point source (NPS) pollution is considered to be the largest single category resulting in water quality deterioration. Pesticide is one of the main detrimental agricultural NPS constituents causing the impairment of water bodies. In this study, a mountainous wetland located in McDowell County, North Carolina, was selected to demonstrate the effects of the natural wetland system on the removal of NPS pesticide (atrazine) pollution to maintain the surface water quality. The selected wetland receives water from two unnamed creeks, which drain primarily agricultural lands. The hydraulic retention time (HRT) for the wetland was approximately 10.5 days based on the results from a dye release study. Water quality monitoring of the wetland was conducted from March to October 1998. One major storm and baseline water quality samples were analyzed. Analytical results indicate that the wetland completely removed NPS atrazine flushed from the upgradient agricultural lands. Laboratory microcosm experiments were conducted to evaluate the feasibility of using the wetland sediments as the microbial sources to enhance the atrazine biodegradation. Microcosm results suggest that atrazine can be degraded under anaerobic or reductive dechlorinating conditions when sucrose was provided as the primary substrate. Atrazine can also serve as the nitrogen source for the growth of microorganisms under anaerobic conditions. Results from this study can provide us with further knowledge on evaluating the role of wetlands in controlling pesticide pollutants from stormwater runoff.


Author(s):  
Shalini Saxena

Wetlands, either constructed or natural, offer a cheaper and low-cost alternative technology for wastewater treatment. A constructed wetland system that is specifically engineered for water quality improvement as a primary purpose is termed as a ‘Constructed Wetland Treatment System’ (CWTS). In the past, many such systems were constructed to treat low volumes of wastewater loaded with easily degradable organic matter for isolated populations in urban areas. However, widespread demand for improved receiving water quality, and water reclamation and reuse, is currently the driving force for the implementation of CWTS all over the world. Recent concerns over wetland losses have generated a need for the creation of wetlands, which are intended to emulate the functions and values of natural wetlands that have been destroyed. Natural characteristics are applied to CWTS with emergent macrophyte stands that duplicate the physical, chemical and biological processes of natural wetland systems. The number of CWTS in use has very much increased in the past few years. The use of constructed wetlands is gaining rapid interest. Most of these systems cater for tertiary treatment from towns and cities. They are larger in size, usually using surface-flow system to remove low concentration of nutrient (N and P) and suspended solids. However, in some countries, these constructed wetland treatment systems are usually used to provide secondary treatment of domestic sewage for village populations. These constructed wetland systems have been seen as an economically attractive, energy-efficient way of providing high standards of wastewater treatment by the help of Phragmite karka plant. Typically, wetlands are constructed for one or more of four primary purposes: creation of habitat to compensate for natural wetlands converted for agriculture and urban development, water quality improvement, flood control, and production of food and fiber.


2017 ◽  
Vol 05 (06) ◽  
pp. 121-132
Author(s):  
Ismail Karaoui ◽  
Abdelkrim Arioua ◽  
Abdelkhalek El Amrani Idrissi ◽  
Wafae Nouaim ◽  
Driss Elhamdouni ◽  
...  

2014 ◽  
Vol 522-524 ◽  
pp. 979-982
Author(s):  
Chuan Bao Wu ◽  
Xiang Hui Zeng

Water quality of Poyang Lake is facing serious threats with the quick development of Jiangxi Province. Water quality control and pollution prevention of Poyang Lake have become important problems set before Jiangxi Province. To keep good water quality of Poyang Lake, a series of pollution-preventing strategies were studied. In order to prevent point source (PS) pollution, industrial types and layout, management measures and production technique should be improved. Strategies to prevent non-point source (NPS) pollution include four aspects. First is to transform part of NPS pollution to PS pollution by rationally laying out industry system. Second is to construct spatially harmonious and reasonable landscape pattern. Third is to reform conventional agricultural production by using advanced chemical and biological technologies. Fourth is to carry out Best Management Practices (BMPs) and Low-impact Development (LID) by learning and innovation.


2013 ◽  
Vol 16 (1) ◽  
pp. 114-129 ◽  
Author(s):  
Haijun Wang ◽  
Wenting Zhang ◽  
Song Hong ◽  
Yanhua Zhuang ◽  
Hongyan Lin ◽  
...  

Non-point source (NPS) pollution has become the major reason for water quality deterioration. Due to the differences in the generation and transportation mechanisms between urban areas and rural areas, different models are needed in rural and urban places. Since land use has been rapidly changing, it is difficult to define the study area as city or country absolutely and the complex NPS pollution in these urban–rural mixed places are difficult to evaluate using an urban or rural model. To address this issue, a fuzzy system-based approach of modeling complex NPS pollutant is proposed concerning the fuzziness of each land use and the ratio of belonging to an urban or rural place. The characteristic of land use, impact of city center and traffic condition were used to describe spatial membership of belonging to an urban or rural place. According to the spatial membership of belonging to an urban or rural place, the NPS distributions calculated by the urban model and rural model respectively were combined. To validate the method, Donghu Lake, which is undergoing rapid urbanization, was selected as the case study area. The results showed that the urban NPS pollutant load was significantly higher than that of the rural area. The land usage influenced the pollution more than other factors such as slope or precipitation. It also suggested that the impact of the urbanization process on water quality is noteworthy.


2013 ◽  
Vol 10 (11) ◽  
pp. 14463-14493
Author(s):  
B. B. Huang ◽  
D. H. Yan ◽  
H. Wang ◽  
B. F. Cheng ◽  
X. H. Cui

Abstract. Under the background of climate change and human's activities, there has been presenting an increase both in the frequency of droughts and the range of their impacts. Droughts may give rise to a series of resources, environmental and ecological effects, i.e. water shortage, water quality deterioration as well as the decrease in the diversity of aquatic organisms. This paper, above all, identifies the impact mechanism of drought on the surface water quality of the basin, and then systematically studies the laws of generation, transfer, transformation and degradation of pollutants during the drought, finding out that the alternating droughts and floods stage is the critical period during which the surface water quality is affected. Secondly, through employing indoor orthogonality experiments, serving drought degree, rainfall intensity and rainfall duration as the main elements and designing various scenario models, the study inspects the effects of various factors on the nitrogen loss in soil as well as the loss of non-point sources pollution and the leaching rate of nitrogen under the different alternating scenarios of drought and flood. It comes to the conclusion that the various factors and the loss of non-point source pollution are positively correlated, and under the alternating scenarios of drought and flood, there is an exacerbation in the loss of ammonium nitrogen and nitrate nitrogen in soil, which generates the transfer and transformation mechanisms of non-point source pollution from a micro level. Finally, by employing the data of Nenjiang river basin, the paper assesses the impacts of drought on the surface water quality from a macro level.


2010 ◽  
Vol 61 (10) ◽  
pp. 2549-2555 ◽  
Author(s):  
C. Y. Wu ◽  
C. M. Kao ◽  
C. E. Lin ◽  
C. W. Chen ◽  
Y. C. Lai

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.


Sign in / Sign up

Export Citation Format

Share Document