Resistance of Plants on Sanitary Landfill in Beijing

Phytoremediation of sanitary landfills has been widely used in recent years, and the research on vegetation resistance is the essential premise. An investigation was undertaken in a sanitary landfill in Changping District of Beijing and the range of CH4 contents on the site was 165.36-1400.99 mg/(m(2).h). Medicago sativa Linn, Potentilla chin-ensis Ser, Taraxacum officinale, Ixeris sonchifolia, Viola verecumda A.Gray, Ostericum sieboldii (Miq.) Nakai and Chenopodium album Linn. were investigated, their superoxide dismutase (SOD) activities, catalase (CAT) activities, proline, ascorbic acid (AA) and H2O2 contents were determined. The results showed the discrepancy of each factor for diverse plants. The reason was that each parameter had different sensitivity to oxidative stress. Results of synthetical evaluation by fuzzy membership degree method indicated that Taraxacum officinale, Potentilla chinensis Ser. and Ostericum sieboldii (Miq.) Nakai had better resistance than other plants growing on the site at that time. The contents of AA and proline of Taraxacum officinale were much higher than others, it also had higher concentration of H2O2, which caused the higher concentration of protective factors; Potentilla chinensis Ser. had highest antioxidant enzymes activities and lowest content of H2O2; the contents of most factors of Ostericum sieboldii (Miq.) Nakai were higher than those of other plants. These three plants could take precedence of all other plants to be cultivated for landfill restoration.