Abstract:

The study aims to verify the application effect of the improved sewage sludge on yield and heavy metal accumulation amount of crop, and provide reference for practical use of sludge. A pot experiment in the laboratory was conducted and seven different iron salt treatments were designed, to comparatively investigate the plant growth and five heavy metal accumulation amount in Chrysanthemum coronarium. The results showed that there was significant difference of dry matters of Chrysanthemum coronarium under deferent Fe salt treatments. The dry matter of CK, A, B and C treatments was 3.59-7.49 g/pot, and that of D, E and F was 11.75-19.27 g/pot, and the value of D was 5.3 times that of B. Under normal condition, heavy metal contents in sewage sludge were generally inferior to the National Standard of Mud of China. When sewage sludge was applied to Chrysanthemum coronarium, the accumulation amount of Cu, As, Pd and Cd in plant were lower than that in the Food Safety Standard of China, but Cr exceeded 4.98-6.66 times that of the standard. In summary, several heavy metals in Chrysanthemum coronarium have better enrichment effect after sludge application. Dry matter of Chrysanthemum coronarium could be largely improved under 3% ferric sulphate and 2% ferrous chloride, followed by 3%FeCl₃ treatment.

Key words: Chrysanthemum coronarium, Heavy Metal, Biomass, Nutrition Uptake