Phytoextraction of arsenic from soil by Leersia oryzoides.
The potential of Leersia oryzoides (rice-cut grass) to remediate arsenic-contaminated soil was studied in greenhouse pot experiments. Leersia oryzoides grown in soil amended with arsenic to a concentration of 110 mg kg(-1), extracted up to 305 mg kg(-1) and 272 mg kg(-1) arsenic into its shoots and roots, respectively, giving a shoot:root quotient of 1.12 and phytoextraction coefficients up to 2.8. Plants in the arsenic-amended soil showed visible signs of stress in the first 8 wk of growth, but then recovered. Based on the 132 plants that were grown in a surface area of approximately 180 cm2, the calculated total arsenic taken up by shoots is 120, 130, and 130 g ha(-1) at 6, 10, and 16 wk, respectively, suggesting that additional arsenic could be removed by periodic mowing over a growing season. Extraction with a mixture of nitric acid and hydrogen peroxide indicated that the available arsenic was constant after the first 6 wk. Uptake is comparable to that reported for duckweed (Lemna gibba L.) and overlaps the low end of the values reported for Chinese brake fern (Pteris Vittata L.)
Ampiah-Bonney
R J
RJ
Department of Chemistry, University of Massachusetts, Lederle Graduate Research Center, Amherst, Massachusetts 01003, USA.
Tyson
J F
JF
Lanza
G R
GR
D001151:Arsenic / Q000302:isolation & purification* / Q000378:metabolism; D018517:Plant Roots / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000254:growth & development / Q000378:metabolism; D006109:Poaceae / Q000254:growth & development / Q000378:metabolism*; D012987:Soil / Q000032:analysis*
D012987:Soil; D001151:Arsenic