title: Repeated phytoextraction of four metal-contaminated soils using the cadmium/zinc hyperaccumulator Sedum plumbizincicola.
abstract: A cadmium/zinc hyperaccumulator extracted metals from four contaminated soils over three years in a glasshouse experiment. Changes in plant metal uptake and soil total (aqua regia-extractable) and available metals were investigated. Plant Cd concentrations in a high-Cd acid soil and plant Zn concentrations in two acid soils decreased during repeated phytoextraction and were predicted by soil available metal concentrations. However, on repeated phytoextraction, plant Cd concentrations remained constant in lightly Cd-polluted acid soils, as did plant Cd and Zn in alkaline soils, although soil available metal concentrations decreased markedly. After phytoextraction acid soils showed much higher total metal removal efficiencies, indicating possible suitability of phytoextraction for acid soils. However, DGT-testing, which takes soil metal re-supply into consideration, showed substantial removal of available metal and distinct decreases in metal supply capacity in alkaline soils after phytoextraction, suggesting that a strategy based on lowering the bioavailable contaminant might be feasible.
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Zhu
authors.initials: Z
authors.lastname: Li
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China. Electronic address: lhwu@issas.ac.cn.
authors.forename: Longhua
authors.initials: L
authors.lastname: Wu
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China.
authors.forename: Pengjie
authors.initials: P
authors.lastname: Hu
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China; Yantai Institute of Coastal Zone Research, Yantai 264003, People's Republic of China.
authors.forename: Yongming
authors.initials: Y
authors.lastname: Luo
authors.affiliation: Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, United Kingdom.
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, People's Republic of China.
authors.forename: Peter
authors.initials: P
authors.lastname: Christie
mesh_terms: D001673:Biodegradation, Environmental; D008670:Metals / Q000032:analysis / Q000378:metabolism*; D031963:Sedum / Q000502:physiology*; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*
chemical_list: D008670:Metals; D012987:Soil; D012989:Soil Pollutants
keywords: Bioavailable contaminated stripping (BCS); Diffusive gradients in thin-films (DGT); Metal bioavailability; Phytoremediation