Phytoremediation of selenium by two helophyte species in subsurface flow constructed wetland

• Published in: Chemosphere (Oxford) 2003-03, Vol.50 (8), p.967-973
• Main Authors: Shardendu, Salhani, N., Boulyga, S.F., Stengel, E.
• Format: Article
• Language: English
• Subjects: Applied sciences; artificial wetlands; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of waters; Biotechnology; Constructed wetlands; Ecosystem; Environment and pollution; Environment Design; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; General purification processes; Industrial applications and implications. Economical aspects; Phragmites; Phragmites australis; Phytoremediation; Plant Leaves - chemistry; Poaceae - chemistry; Poaceae - physiology; Pollution; Selenium; Selenium - isolation & purification; Selenium - pharmacokinetics; Typha; Typha latifolia; Typhaceae - chemistry; Typhaceae - physiology; Wastewaters; Water Movements; Water Pollutants - isolation & purification; Water Pollutants - pharmacokinetics; Water Purification - methods; Water treatment and pollution
• ISSN: 0045-6535; 1879-1298
• DOI: 10.1016/S0045-6535(02)00607-0

The phytoremediation of selenium by two different wetland species was investigated. Selenium (20.4 μg/l) was supplied continuously to subsurface flow constructed wetlands, one vegetated with Typha latifolia L. and the other with Phragmites australis (Cav.) Trin. ex Steud. The beds of both species had same hydraulic loading rate (0.079 m 3/m 2/d) and water retention time (24 h). However, the mass loading rate was 1.27 mg Se/m 2/d for Phragmites and 1.35 mg Se/m 2/d for Typha. In the Typha bed Se migrated faster than in the Phragmites bed. After 25 d of Se supplementation in the Typha bed about 54% of the Se inlet concentration remained in the outlet water. In the Phragmites bed Se was removed completely from the water after passing through 3/4 of the bed length. After 65 d of Se supplementation the highest amount of Se (2.8 μg/g dry matter) was determined in the organic material of the Typha bed. Roots and rhizomes accumulated 2.2 and 1.8 μg/g dry matter respectively. Phragmites accumulated Se in the leaves and stems, but not in the rhizomes. The accumulation in the leaves (1.8 μg Se/g dry matter) was three times higher than in the stems (0.6 μg Se/g dry matter).