Phytotoxicity of biosolids and screening of selected plant species with potential for mercury phytoextraction.

Autor: Lomonte C; School of Chemistry, The University of Melbourne, Victoria 3010, Australia. c.lomonte@pgrad.unimelb.edu.au, Doronila AI, Gregory D, Baker AJ, Kolev SD
Jazyk: angličtina
Zdroj: Journal of hazardous materials [J Hazard Mater] 2010 Jan 15; Vol. 173 (1-3), pp. 494-501. Date of Electronic Publication: 2009 Aug 31.
DOI: 10.1016/j.jhazmat.2009.08.112
Abstrakt: Mercury contaminated stockpiles of biosolids (3.5-8.4 mg kg(-1) Hg) from Melbourne Water's Western Treatment Plant (MW-WTP) were investigated to evaluate the possibility for their phytoremediation. Nine plant species (Atriplex codonocarpa, Atriplex semibaccata, Austrodanthonia caespitosa, Brassica juncea, Brassica napus, Gypsophila paniculata, Sorghum bicolor, Themeda triandra and Trifolium subterraneum) were screened for phytoextraction potential in Hg-contaminated biosolids from MW-WTP. In addition, the same plant species were germinated and grown in two other substrates (i.e. potting mix and potting mix spiked with mercury(II)). Growth measurements and the mercury uptake for all three substrates were compared. Some plant species grown in potting mix spiked with mercury(II) grew more vigorously than in the other two substrates and showed higher levels of sulphur in their tissues. These results suggested that the mercury stress activated defence mechanisms and it was hypothesised that this was the likely reason for the enhanced production of sulphur compounds in the plant species studied which stimulated their growth. Some species did not grow in biosolids because of the combined effect of high mercury toxicity and high salt content. Atriplex conodocarpa and Australodanthonia caespitose proved to be the most suitable candidates for mercury phytoextraction because of their ability to translocate mercury from roots to the above-ground tissues.
Databáze: MEDLINE