Phytoremediation of arsenic-contaminated groundwater using arsenic hyperaccumulator Pteris vittata L.: effects of frond harvesting regimes and arsenic levels in refill water.
A large-scale hydroponic system to phytoremediate arsenic-contaminated groundwater using Pteris vittata (Chinese brake fern) was successfully tested in a field. In this 30-wk study, three frond-harvesting regimes (all, mature, and senescing fronds) and two water-refilling schemes to compensate for evapotranspiration (high-As water of 140-180 μg/L and low-As water of <7 μg/L) were investigated. Two experiments (Cycle 1 and Cycle 2) were conducted using the same plants in 24 tanks with each containing 600 L of arsenic-contaminated groundwater and 32 ferns. During Cycle 1 and with initial As of 140 μg/L, As in tanks refilled with low-As water was reduced to <10 μg/L in 8 wks compared to <10 μg/L in 17 wks in tanks refilled with high-As water. During Cycle 2 and with initial As of 180 μg/L, the remediation time was reduced by 2-5 wks, indicating that more established ferns were more efficient. In areas where clean water is limiting, refilling high-As water coupled with harvesting senescing fronds is recommended for more effective As phytoremediation.
University of Florida, Mid-Florida Research and Education Center, Department of Environmental Horticulture, Apopka, FL 32703, USA.
Seenivasan
S
Natarajan
Robert H
RH
Stamps
Lena Q
LQ
Ma
Uttam K
UK
Saha
Damaris
D
Hernandez
Yong
Y
Cai
Edward J
EJ
Zillioux
D001151:Arsenic / Q000302:isolation & purification* / Q000378:metabolism; D001673:Biodegradation, Environmental; D052918:Environmental Restoration and Remediation / Q000379:methods*; D032495:Pteris / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000378:metabolism*
D014874:Water Pollutants, Chemical; D001151:Arsenic