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Measuring Phosphorus Release in Laboratory Microcosms for Water Quality Assessment
Published on: July 22, 2019
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Magnetite-modified activated carbon based capping and mixing technology for sedimentary phosphorus release control
Jianwei Lin1, Yan Wang1, Yanhui Zhan1
1College of Marine Ecology and Environment, Shanghai Ocean University, Shanghai, 201306, China.
Journal of Environmental Management
|July 24, 2019
Summary
Magnetite-modified activated carbon (MAC) effectively controls sedimentary phosphorus release. MAC capping is more efficient than amendment for reducing phosphorus in overlying water and sediment.
Area of Science:
- Environmental Chemistry
- Water Quality Management
- Materials Science
Background:
- Sedimentary phosphorus (P) release is a major cause of eutrophication.
- Controlling P mobilization from sediments is crucial for aquatic ecosystem health.
Purpose of the Study:
- To synthesize and characterize magnetite-modified activated carbon (MAC).
- To evaluate MAC as a capping and amendment material for controlling sedimentary P release.
- To compare the efficacy of MAC capping versus amendment.
Main Methods:
- Batch experiments for phosphate adsorption/desorption on MAC.
- Sediment incubation experiments to assess MAC's impact on P mobilization.
- Analysis of reactive soluble P (RS-P) in overlying water.
- Measurement of labile P using diffusive gradient in thin-films (DGT).
Main Results:
- MAC capping and amendment reduced RS-P in overlying water by over 83%.
- Both methods significantly decreased labile P in upper sediment, forming a P-S-Layer.
- MAC adsorbed mainly redox-sensitive P (PRS), NaOH extractable inorganic P (IPNaOH), and HCl extractable P (PHCl).
- MAC capping demonstrated higher efficiency in reducing P efflux than amendment.
Conclusions:
- MAC capping and amendment are effective strategies to inhibit sedimentary P release.
- MAC capping offers superior control over sedimentary P liberation compared to amendment.
- Retrieval of MAC after application is recommended due to the nature of adsorbed P.
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