污泥中不同铁盐对大叶茼蒿吸收重金属的影响

Effect of Different Fe Salt on Uptake of Heavy Metal by Chrysanthemum coronarium in Sewage Sludge

通过验证处理后的生活污泥在农作物上对产量和重金属吸收量的影响,以期为污泥实际应用积累基础。在盆栽条件下,通过7种不同的铁盐处理进行试验,从大叶茼蒿的生长情况、5种重金属积累量进行比较。结果表明:在不同铁盐处理中大叶茼蒿在污泥上的干物质有显著差异。处理CK、A、B、C干物质为3.59~7.49 g/盆,D、E、F为11.75~19.27 g/盆,处理D和B大小差别可达5.3倍。在正常情况下,污泥的重金属含量一般低于国家泥质标准。施用污泥的茼蒿重金属植株积累量Cu、As、Pb、Cd也在食品安全的标准范围内,但重金属Cr含量要超标4.98~6.66倍。施用污泥后茼蒿对某些重金属有较好的富集作用,但在产量上不同铁盐处理中以3%硫酸亚铁(FeSO_(4)·7H_(2)O)+2%FeCl_(2)处理最好,3%FeCl_(3)次之。

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 was11.75-19.27 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%FeCl_(3) treatment.