title: Effects of plant arsenic uptake and heavy metals on arsenic distribution in an arsenic-contaminated soil.
abstract: This study examined the effects of heavy metals and plant arsenic uptake on soil arsenic distribution. Chemical fractionation of an arsenic-contaminated soil spiked with 50 or 200mg kg(-1) Ni, Zn, Cd or Pb was performed before and after growing the arsenic hyperaccumulator Pteris vittata L for 8weeks using NH(4)Cl (water-soluble plus exchangeable, WE-As), NH(4)F (Al-As), NaOH (Fe-As), and H(2)SO(4) (Ca-As). Arsenic in the soil was present primarily as the recalcitrant forms with Ca-As being the dominant fraction (45%). Arsenic taken up by P. vittata was from all fractions though Ca-As contributed the most (51-71% reduction). After 8weeks of plant growth, the Al-As and Fe-As fractions were significantly (p<0.01) greater in the metal-spiked soils than the control, with changes in the WE-As fraction being significantly (p=0.007) correlated with plant arsenic removal. The plant's ability to solubilize soil arsenic from recalcitrant fractions may have enhanced its ability to hyperaccumulate arsenic.
authors.affiliation: Soil and Water Science Department, University of Florida, Gainesville, FL 32611-0290, USA.
authors.forename: Abioye O
authors.initials: AO
authors.lastname: Fayiga
authors.forename: Lena Q
authors.initials: LQ
authors.lastname: Ma
authors.forename: Qixing
authors.initials: Q
authors.lastname: Zhou
mesh_terms: D001151:Arsenic / Q000032:analysis / Q000493:pharmacokinetics*; D002104:Cadmium / Q000737:chemistry; D002118:Calcium / Q000737:chemistry; D004784:Environmental Monitoring / Q000379:methods; D006863:Hydrogen-Ion Concentration; D007854:Lead / Q000737:chemistry; D019216:Metals, Heavy / Q000737:chemistry*; D009532:Nickel / Q000737:chemistry; D032495:Pteris / Q000737:chemistry* / Q000378:metabolism; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000737:chemistry* / Q000493:pharmacokinetics; D012995:Solubility; D015032:Zinc / Q000737:chemistry
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D007854:Lead; D009532:Nickel; D015032:Zinc; D001151:Arsenic; D002118:Calcium