Abstract:

In order to research the effects of remedying heavy metal polluted soil with washing chemicals, the heavy metal polluted soil, on where plants were not able to grow, was remedied by chemical washing. The washing chemicals of water, lime solution and EDTA solution were used single or combinational to sequential wash soil. Four crops of rice, soybean, corn and pumpkin were planted on treated soil in order to assess effects of chemical. The results indicated that water, lime solution and EDTA solution could extract heavy metals from soil, but their ability were different, with EDTA solution>water>lime solution. The four crops were able to germinate on treated soils, but all crops were all phytotoxic and died after germination on the soil washed by water or EDTA solution. The biomass of plants grown on the soils washed by lime solution or water +lime solution was higher than that of other treatments. All crops accumulated more heavy metals from remedied soils than that from normal soil, but the accumulating ability of soybean and rice to heavy metals was higher than corn and pumpkin. The conclusion was that lime was able to reduce toxicity and was a good amender for remedying the polluted soil by heavy metals; the accumulating abilities to heavy metals of soybean and rice were higher than that of corn and pumpkin.