The effect of emergent macrophytes on the dynamics of sulfur species and trace metals in wetland sediments.
This study focuses on the effect of plants on the biogeochemistry of sulfur species and the mobility of heavy metals in wetland sediments. Results showed that, in the presence of plants, sediments had elevated sulfate concentrations in the rhizosphere during the growing season, ranging from 0.2 to 6.20 mmol L(-1), whereas only a small difference in the sulfate profiles between vegetated and non-vegetated sediments was observed during senescence. Based on the sulfate concentration increase, the oxygen release rate from the roots to achieve the corresponding oxidation of sulfide was estimated as 0.85 g m(-2) day(-1). Evapotranspiration-induced advection is a major contributor to the transport of sulfate from the water column into the sediments, and also allows dissolved trace metals (i.e. Cd, Pb, and Zn) to be transported into the sediments and react with the acid volatile sulfide pool, resulting in the immobilization of trace metals in these sediments.
Choi
Jung Hyun
JH
Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, USA.
Park
Seok Soon
SS
Jaffé
Peter R
PR
D002104:Cadmium / Q000032:analysis; D017753:Ecosystem; D004785:Environmental Pollutants / Q000032:analysis*; D019015:Geologic Sediments / Q000032:analysis*; D007854:Lead / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis*; D010084:Oxidation-Reduction; D063245:Plant Development; D018517:Plant Roots / Q000502:physiology; D018526:Plant Transpiration; D012621:Seasons; D013431:Sulfates / Q000032:analysis; D013440:Sulfides / Q000032:analysis; D013457:Sulfur Compounds / Q000032:analysis*; D015032:Zinc / Q000032:analysis
D004785:Environmental Pollutants; D019216:Metals, Heavy; D013431:Sulfates; D013440:Sulfides; D013457:Sulfur Compounds; D002104:Cadmium; D007854:Lead; D015032:Zinc