Nitrate Removal in Shallow, Open-Water Treatment Wetlands

2014 ◽  
Vol 48 (19) ◽  
pp. 11512-11520 ◽  
Author(s):  
Justin T. Jasper ◽  
Zackary L. Jones ◽  
Jonathan O. Sharp ◽  
David L. Sedlak
Keyword(s):  
Water Treatment ◽  
Nitrate Removal ◽  
Open Water ◽  
Treatment Wetlands

scholarly journals Biomat Resilience to Desiccation and Flooding Within a Shallow, Unit Process Open Water Engineered Wetland

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 815
Author(s):  
Adam R. Brady ◽  
Michael A. Vega ◽  
Kimberly N. Riddle ◽  
Henry F. Peel ◽  
Evelyn J. Lundeen ◽  
...  
Keyword(s):  
Water Treatment ◽  
Photosynthetic Activity ◽  
Negative Impact ◽  
Nitrate Removal ◽  
Open Water ◽  
Aquifer Recharge ◽  
Unit Process ◽  
Natural Treatment ◽  
System Resilience ◽  
The Impact

Projections of increased hydrological extremes due to climate change heighten the need to understand and improve the resilience of our water infrastructure. While constructed natural treatment analogs, such as raingardens, wetlands, and aquifer recharge, hold intuitive promise for variable flows, the impacts of disruption on water treatment processes and outcomes are not well understood and limit widespread adoption. To this end, we studied the impact of desiccation and flooding extremes on demonstration-scale shallow, unit process open water (UPOW) wetlands designed for water treatment. System resilience was evaluated as a function of physical characteristics, nitrate removal, photosynthetic activity, and microbial ecology. Rehydrated biomat that had been naturally desiccated re-established nitrate removal consistent with undisrupted biomat in less than a week; however, a pulse of organic carbon and nitrogen accompanied the initial rehydration phase. Conversely, sediment intrusion due to flooding had a negative impact on the biomat’s photosynthetic activity and decreased nitrate attenuation rates by nearly 50%. Based upon past mechanistic inferences, attenuation potential for trace organics is anticipated to follow similar trends as nitrate removal. While the microbial community was significantly altered in both extremes, our results collectively suggest that UPOW wetlands have potential for seasonal or intermittent use due to their promise of rapid re-establishment after rehydration. Flooding extremes and associated sediment intrusion provide a greater barrier to system resilience indicating a need for proactive designs to prevent this outcome; however, residual treatment potential after disruption could provide operators with time to triage and manage the system should a flood occur again.

Nitrate removal and denitrification affected by soil characteristics in nitrate treatment wetlands

2007 ◽  
Vol 42 (4) ◽  
pp. 471-479 ◽  
Author(s):  
Ying-Feng Lin ◽  
Shuh-Ren Jing ◽  
Der-Yuan Lee ◽  
Yih-Feng Chang ◽  
Kai-Chung Shih
Keyword(s):  
Nitrate Removal ◽  
Soil Characteristics ◽  
Treatment Wetlands ◽  
Nitrate Treatment

Design of the treatment wetland determines nitrous oxide emission

2021 ◽  
Author(s):  
Kuno Kasak ◽  
Keit Kill ◽  
Evelyn Uuemaa ◽  
Ülo Mander
Keyword(s):  
Nitrous Oxide ◽  
Water Treatment ◽  
Water Table ◽  
Water Table Depth ◽  
Treatment Wetlands ◽  
Phosphorus Compounds ◽  
Nitrogen And Phosphorus ◽  
Treatment Wetland ◽  
Vegetation Growth ◽  
Sampling Campaign

<p>Treatment wetlands are widespread measures to reduce agricultural diffuse pollution. Systems that are often planted with emergent macrophytes such as Typha spp. and Phragmites spp. are efficient to reduce nutrients, particularly nitrogen and phosphorus compounds. While many experiments have been conducted to study the emission of carbon dioxide (CO<sub>2</sub>) and methane (CH<sub>4</sub>), little attention has been paid for the emission of nitrous oxide (N<sub>2</sub>O). Few studies have been shown that usually N<sub>2</sub>O emission from water saturated ecosystems such as wetlands is low to negligible. In Vända in-stream treatment wetland that was built in 2015 and located in southern Estonia, we carried out first long term N<sub>2</sub>O measurements using floating chambers. The total area of the wetland is roughly .5 ha; 12 boardwalks, each equipped with two sampling spots, were created. Samples were collected biweekly from March 2019 through January 2021. In each sampling campaign water table depth, water and air temperature, O<sub>2</sub> concentration, oxygen reduction potential, pH and electrical conductivity were registered. Water samples for TN, NO<sub>3</sub>-N, NO<sub>2</sub>-N, TOC, TIC and TC were collected from inflow and outflow of the system in each sampling session and the average concentrations were 5.1 mg/L, 3.68 mg/L, <0.1 mg/L, 41.2 mg/L and 28.7, respectively. Our results showed a very high variability of N<sub>2</sub>O emission: the fluxes ranged from -4.5 ug m<sup>-2</sup> h<sup>-1</sup> to 2674.2 ug m<sup>-2</sup> h<sup>-1</sup> with mean emission of 97.3 ug m<sup>-2</sup> h<sup>-1</sup>. Based on gas samples (n=687) we saw a strong correlation (R<sup>2</sup> = -0.38, p<0.0001) between N<sub>2</sub>O emission and water depth. The average N<sub>2</sub>O emission from sections with the water table depth >15 cm was 45.9 ug m<sup>-2</sup> h<sup>-1</sup> while sections with water table depth <15 cm showed average emission of 648.3 ug m<sup>-2</sup> h<sup>-1</sup>. The difference between these areas was more than 10 times. Water temperature that is often considered as the main driver had less effect to the N<sub>2</sub>O emission. For instance, at lower temperatures, when the emissions from deeper zones decreased, there was no temperature effect on emissions from shallow zones. We also saw that over the years the overall N<sub>2</sub>O emission followed clear seasonal dynamics and has a slight trend towards lower emissions. This can be related to the more intensive vegetation growth that has been increased from ~40% in 2019 to approximately 90% in 2020. Our study demonstrates that the design of the wetland is not only important for the water treatment, but it can also determine the magnitude of greenhouse gas emissions. We saw that even slight changes in water table depth can have a significant effect on the annual N<sub>2</sub>O emission. Thus, in-stream treatment wetlands that have water table depth at least 15 cm likely have remarkably lower N<sub>2</sub>O emissions without losing water treatment efficiency.</p><p> </p>

NATIVE PLANT MATERIAL SELECTION FOR WATER TREATMENT WETLANDS

2009 ◽  
Vol 2009 (1) ◽  
pp. 1436-1454
Author(s):  
C. R. Taylor ◽  
P. B. Hook ◽  
C. A. Zabinski ◽  
O.R. Stein
Keyword(s):  
Water Treatment ◽  
Plant Material ◽  
Material Selection ◽  
Treatment Wetlands ◽  
Native Plant ◽  
Selection For

Catalytic Nitrate Removal in a Trickle Bed Reactor: Direct Drinking Water Treatment

Opflow ◽  
2017 ◽  
Vol 109 ◽  
pp. E144-E157 ◽  
Author(s):  
Madison Bertoch ◽  
Allison M. Bergquist ◽  
Gary Gildert ◽  
Timothy J. Strathmann ◽  
Charles J. Werth
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Nitrate Removal ◽  
Drinking Water Treatment ◽  
Trickle Bed Reactor ◽  
Trickle Bed
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