Study On The Effect Of Different Restorative Agents On The Soil Contamination Of Pb And Cd

The experiment is to evaluate the effect of restoration by plant Chinese cabbage into soil contains heavy metal lead and cadmium,and to access the effect of restoration simulated in light composite lead and cadmium pollution soil by using different restoration agent(Jinwuzong,ferrous metal biochar,silica agent)through different affects such as the content of heavy metal in the soil,plant accumulation,plant’s physiological and biochemical and nutritional quality.Also I have studied the physiological and biochemical effects on plant of heavy metals and restorative agents.The conclusions are as follows:1.The pH value of soil(p<0.01)could be significantly improved by the treatment of Jinwuzong and ferrous metald biochar.Jingwuzong significantly reduced the heavy metal content of cadmium in soil(p<0.01).silica agent significantly reduced the heavy metal content of cadmium in soil(p<0.05).The data showed that the effect of the restoration of soil lead begin to work obviously on the 25th day.2.The results of observation is that parts of lead enrichment coefficient found in Chinese cabbage changes regularly with time,also concluded that the equation between time(from 10 to 30 days)and lead enrichment coefficient is y=0.0188x~2-0.0982x+0.2316 R~2=0.9957.which provide some theoretical basis and materials for the repair of the soil with mild pollution.3.From the amount of lead accumulated in the plant floor,Jingwuzong decreased by 36%,the the ferrous metal biochar treatment group decreased by 94%,and silica blade surface decreased by 23%.There was a significant difference in the lead content of the ground plants in the Jingwuzong treatment group and the control group(P<0.05).The lead accumulation in the underground part of the plant showed that the Jingwuzong group decreased by 76%,the ferrous metald biochar group decreased by 75%,and silica blade surface was 90%lower than the control CK.4.The accumulation of cadmium in the subsoil of Jinwuzong group decreased by 45.3%,the ferrous metal biochar treatment group decreased by 69.1%,and the treatment of silica leaf barrier agent decreased by 38.8%.There were significant differences between the two treatment groups and the blank control(P<0.05).The accumulation of cadmium in the underground part of the plant decreased by 45.3%in Jinwuzong group,68.3%in ferrous metald biochar group and 38.8%in silica blade surface.5.The treatment of three kinds of restorative agents has significantly reduced the concentration of lead and the concentration of pb.The reduction of the concentration coefficient of lead in the aboveground and underground parts of the cabbages with ferrous metal biochar,Jinwuzong and silica blade surface has obvious effect.The change in the enrichment coefficient of cadmium is obvious from 20 to 25 days.The effect of silicon dioxide on lead concentration in the underground part of cabbages was better than that of the other two treatment groups.6.From CAT(catalase enzyme activity),Jinwuzong group has fallen by 70%comparatively,the ferrous metal biochar group than in control group fell 30%comparatively,silica,blocking agent was 43%lower than control(CK).At this concentration,soil lead content significantly activated CAT(p<0.01).7.As of Activity of peroxidase(POD),Jinwuzong group fell 26.6%comparatively,ferrous metal biochar dropped 28.1%comparatively,silica,blocking agent group than in control(CK)decreased by 35.9%comparatively.The Lead absorbed in plant can significantly inhibit POD enzyme activity(p<0.05).8.Compared with the control group,the chlorophyll in the Jinwuzong treatment group increased by 3.4-41.5%,and the ferrous metal biochar treatment group increased by 13.1%to 37.1%,and the treatment of silica blade surface blocker increased by 25.6%to 52.2%.There was a significant negative correlation between the chlorophyll and the cadmium content of the plants on the ground(p<0.05).9.In terms of nutritional quality,the content of vitamin c and reducing sugar,Jinwuzong treatment,ferrous metal biochar treatment and silica leaf barrier agent were all better than the control group.However,the protein content in blank control group was slightly higher,possibly because heavy metal pollution triggered the plant’s stress response mechanism,which showed a higher protein content.