title: Pteris vittata continuously removed arsenic from non-labile fraction in three contaminated-soils during 3.5 years of phytoextraction.
abstract: We evaluated the effectiveness of arsenic (As) hyperaccumulator Pteris vittata to continuously remove As from three contaminated-soils containing 26-126mgkg(-1) As over 7 harvests in 3.5 years. Changes in As speciation in soils, amended with P fertilizer (P-soil) or insoluble phosphate rock (PR-soil), were assessed via sequential fractionation. Arsenic in available (soluble+exchangeable), non-labile (bound to amorphous+crystalline Fe/Al oxides), and residual fractions constituted ∼12%, ∼80%, and ∼8% of soil As. Soluble As declined while exchangeable As was unchanged, likely due to replenishment from non-labile As, which accounted for ∼87% of decline in total soil As. Although plant-available As is important, the non-labile As better predicted the frond As concentration in P. vittata, with the correlation being r=0.90 and 0.64 for PR-soils and P-soils. P. vittata removed 44% of soil As from PR-soils compared to 33% from P-soils, suggesting the low-soluble P from PR was more effective than P fertilizer in enhancing As uptake by P. vittata. To facilitate acquisition of P from PR, P. vittata produced larger root biomass to solubilize non-labile As, allowing for more efficient phytoextraction.
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States.
authors.forename: Jason T
authors.initials: JT
authors.lastname: Lessl
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Luo
authors.affiliation: State Key Lab of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210046, China; Soil and Water Science Department, University of Florida, Gainesville, FL 32611, United States. Electronic address: Lqma@ufl.edu.
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
mesh_terms: D001151:Arsenic / Q000737:chemistry* / Q000378:metabolism; D001673:Biodegradation, Environmental; D018533:Biomass; D052918:Environmental Restoration and Remediation; D010710:Phosphates / Q000737:chemistry / Q000378:metabolism; D032495:Pteris / Q000737:chemistry* / Q000378:metabolism; D012989:Soil Pollutants / Q000737:chemistry* / Q000378:metabolism
chemical_list: D010710:Phosphates; D012989:Soil Pollutants; D001151:Arsenic
keywords: Contamination; Fractionation; Hyperaccumulation; Phosphate rock; Phytoextraction