Heavy metal's ecological effects of irrigation with landfill site leachate.
Jiang BiLiang, Lan ChongYu, Wang BoSun
Author Affiliation: School of Life Science, Zhongshan University, Guangzhou 510275, China.
China Environmental Science 21 : 18-23
Abstract : The results of a pot culture experiment showed that, after one year of irrigation with landfill leachate, the accumulation of four heavy metals (Cu, Pb, Zn and Cd) in the irrigated soil did not exceed the Chinese national standard allowable values. Soil enzymes were elevated at different levels of leachate in irrigation water but irrigation with leachate had a negative effect. The legumes Acacia confusa and Ormosia pinnata absorbed more heavy metals than non-leguminous species. Their absorption of Cu and Zn was stronger than that of the herbaceous species Vetiveria zizanioides, Cynodon dactylon, Canna indica and Wedelia chinensis, while that of Pb and Cd was weaker. The above-mentioned species, except Canna indica, survived best and had the best purifying ability for leachate pollution. It is concluded that these species are suitable for revegetation of landfill sites.