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Updated: Jul 3, 2026
10:44
Clean Sampling and Analysis of River and Estuarine Waters for Trace Metal Studies
Published on: July 1, 2016
Urban wetlands regulate trace element dynamics at the sediment- water interface.
Xiangyu He1, Wenming Yan1, Xiang Chen2
1State Key Laboratory of Water Disaster Prevention, Hohai University, Nanjing, 210098, China; College of Hydrology and Water Resources, Hohai University, Nanjing, 210098, China.
Environmental Pollution (Barking, Essex : 1987)
|July 1, 2026
Summary
Urban wetlands influence trace element behavior at the sediment-water interface (SWI). Higher organic loads increase the risk of releasing certain elements, necessitating targeted hydrological controls.
Area of Science:
- Environmental Science
- Geochemistry
- Ecology
Background:
- Urban wetlands are vital for hydrological regulation and pollutant interception.
- Biogeochemical mechanisms of trace element dynamics at the sediment-water interface (SWI) in urban wetlands are not well understood.
Purpose of the Study:
- To investigate the vertical distribution and transformation of trace elements in urban wetland sediments.
- To understand the influence of physicochemical conditions, dissolved organic matter (DOM), and iron on trace element dynamics.
Main Methods:
- Analysis of trace element vertical distribution in sediments.
- Investigation of physicochemical conditions at the SWI.
- Multivariate analysis to determine element associations with DOM and iron.
Main Results:
- Trace element pollution loads decreased downstream; most elements had higher pore water than overlying water concentrations.
- As, Co, and W showed positive SWI gradients, while Sb, Ni, and Cd showed negative gradients, indicating selective migration.
- Element variability shifted from DOM control upstream to DOM/Fe redox coupled control in wetland sediments.
Conclusions:
- Urban wetlands significantly alter SWI conditions, influencing trace element dynamics through DOM and iron interactions.
- Wetland conditions promote selective trace element release at the SWI, with higher organic loads potentially increasing release risks.
- Targeted hydrological controls are recommended to mitigate pollution risks in urban wetlands.
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