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Wetland treatment systems are used extensively across the world to mitigate surface runoff. While wetland treatment for nitrogen mitigation has been comprehensively reviewed, the implications of common-use pesticides and antibiotics on nitrogen reduction remain relatively unreviewed. Therefore, this review seeks to comprehensively assess the removal of commonly used pesticides and antibiotics and their implications for nitrogen removal in wetland treatment systems receiving non-point source runoff from urban and agricultural landscapes. A total of 181 primary studies were identified spanning 37 countries. Most of the reviewed publications studied pesticides (n = 153) entering wetlands systems, while antibiotics (n = 29) had fewer publications. Even fewer publications reviewed the impact of influent mixtures on nitrogen removal processes in wetlands (n = 16). Removal efficiencies for antibiotics (35–100%), pesticides (−619–100%), and nitrate-nitrogen (−113–100%) varied widely across the studies, with pesticides and antibiotics impacting microbial communities, the presence and type of vegetation, timing, and hydrology in wetland ecosystems. However, implications for the nitrogen cycle were dependent on the specific emerging contaminant present. A significant knowledge gap remains in how wetland treatment systems are used to treat non-point source mixtures that contain nutrients, pesticides, and antibiotics, resulting in an unknown regarding nitrogen removal efficiency as runoff contaminant mixtures evolve.
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Contaminant removal efficiency of floating treatment wetlands
Abstract Floating treatment wetlands are new ecological infrastructures for stormwater treatment. Despite a recent proliferation in their usage, their contaminant removal efficiencyecontinues to draw research attention. Here, theefrom idealized FTWs is numerically computed across a wide range of flow and geometric conditions while accommodating joint contributions of advection, turbulent dispersion, and vegetation removal. The emerging mathematical structure describingebears resemblance to a simplified plug flow model and supports an empirical shallow-basin model from long-term field measurements. The present model indicates thateremains significantly influenced by a Dämkohler number that quantifies the effects of both vegetation and flow properties. The impacts oneof the underflow region and contaminant blockage on the removal mechanisms are also investigated.
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- PAR ID:
- 10303673
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research Letters
- Volume:
- 15
- Issue:
- 10
- ISSN:
- 1748-9326
- Page Range / eLocation ID:
- Article No. 1040b7
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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