Phytoremediation of Arsenic in Submerged Soil by Wetland Plants

Abstract

Wetland aquatic plants including Canna glauca L., Colocasia esculenta L. Schott, Cyperus papyrus L. and Typha angustifolia L. were used in the phytoremediation of submerged soil polluted by arsenic (As). Cyperus papyrus L. was noticed as the largest biomass producer which has arsenic accumulation capacity of 130–172 mg As/kg plant. In terms of arsenic removal rate, however, Colocasia esculenta L. was recognized as the largest and fastest arsenic remover in this study. Its arsenic removal rate was 68 mg As/m²/day while those rates of Canna glauca L., Cyperus papyrus L. and Typha angustifolia L. were 61 mg As/m²/day, 56 mg As/m²/day, and 56 mg As/m²/day, respectively. Although the 4 aquatic plants were inferior in arsenic accumulation, their high arsenic removal rates were observed. Phytostabilization should be probable for the application of these plants.

KEY WORDS:

• wetland plants
• arsenic
• phytoremediation

ACKNOWLEDGMENTS

Fund for this project was provided by Inter-Department Program in Environmental Management; Hazardous Waste Management (International Program), and Graduate School Chulalongkorn University. The authors gratefully acknowledge EGAT; Mae Moh Power Plant Lampang Province; the Biology and Geology Departments, Science Faculty of Chiang Mai University, and the Soil Science and Conservation Department of the Agriculture Faculty, Chiang Mai University for their support.