title: Effects of nutrient and sulfate additions on As mobility in contaminated soils: a laboratory column study.
abstract: The effect of nutrient and sulfate additions on As mobility in contaminated soils was investigated under advective-flow anoxic columns in this study. The mobility of As in surface contaminated soils was investigated by the leaching of de-ionized water (DI-water), artificial ground water (AG-water) and AG-water+sulfate (Sulfate). After 144 d of experiments, compared to the DI-water column, the total As exported from the columns AG-water and Sulfate was enhanced by seven and eightfold, respectively. The results indicated that the nutrient and sulfate addition significantly enhanced the As mobility in contaminated soils. In low-sulfate soils (DI-water and AG-water systems), As mobilization was primarily attributed to As reduction and to the transformation of amorphous Fe(III) (oxy)hydroxides. In soil with sulfate addition (Sulfate system), besides As reduction and Fe(III) (oxy)hydroxides transformation, the dissolution of As sulfides and the formation of thioarsenic species under sulfidogenic condition were possibly important processes accelerating As release. In conclusion, the addition of the nutrient solution and sulfates may increase the mobility of As in contaminated soils, posing a potential threat to groundwater.
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Song
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Shaofeng
authors.initials: S
authors.lastname: Wang
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China. Electronic address: yongfeng.jia@iae.ac.cn.
authors.forename: Yongfeng
authors.initials: Y
authors.lastname: Jia
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Zidan
authors.initials: Z
authors.lastname: Yuan
authors.affiliation: Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Geological Sciences, University of Saskatchewan, Saskatoon, SK S7N 5E2, Canada.
authors.forename: Mario A
authors.initials: MA
authors.lastname: Goméz
mesh_terms: D001151:Arsenic / Q000032:analysis / Q000737:chemistry*; D002681:China; D005290:Ferric Compounds / Q000737:chemistry*; D060587:Groundwater / Q000737:chemistry; D008751:Methylene Blue; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry*; D052616:Solid Phase Extraction; D013050:Spectrometry, Fluorescence; D013054:Spectrophotometry, Atomic; D013056:Spectrophotometry, Ultraviolet; D013431:Sulfates / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*; D014872:Water Movements
chemical_list: D005290:Ferric Compounds; D012989:Soil Pollutants; D013431:Sulfates; D013440:Sulfides; D001151:Arsenic; D008751:Methylene Blue
keywords: Anoxic soils; Arsenic mobility; Minerals transformation; Reduction; Speciation; Sulfidization