Experimental Study On Phytoremediation Of Heavy Metals In The Surrounding Soil Of A Mining Area In Tongling

Due to the long-term mining,the soil in the abandoned mining area has not been treated with relevant pollution,which has caused a large number of soil in the abandoned mining area to be seriously polluted by heavy metals,so it is in urgent need of treatment.This paper was commissioned by the enterprise to investigate the physical and chemical properties of soil and heavy metal pollution in the wasteland of tongling mining area.Through the geranium and native plants for heavy metal pollution in the region to repair research,determine the dominant plant,through strengthening advantage plant of Tongling city sludge experiment of soil heavy metal repair,tongling mining area the soil phytoremediation experiment scheme,for the phytoremediation of heavy metals in the region to provide the experimental data and theoretical basis.Results showed that?1?As,Pb and Cd in zhongming iron mine exceeded the background value?1990?by 1.27,3.66 and 454.78 times,while Pb and Cd exceeded the risk screening value by 1.50 and 136.43 times,respectively.In xinqiao pyrite,As,Pb and Cd exceeded the background value,3.45,1.95 and 411.22 times of the background value,and As,Pb and Cd exceeded the risk screening value,1.07,1.33and 123.37 times,respectively.In fenghuangshan copper mine,Pb and Cd exceeded the background value by 1.27 times and 407.11 times respectively,while Cd exceeded the risk screening value by 122.13 times and exceeded the risk control value by 23.43times.?2?Different varieties of geranium have different enrichment capacities for heavy metals.The mean value of BCF_Cu is 0.42,and the maximum value of powder and white is 0.57.The mean value of BCF_Zn was 0.58,and the maximum value of horizon was 0.79.The average BCF_Cd was 0.69,and the horizon light blue was the largest at 0.98.The average TF_Cu was 0.87,and the white powder was 1.31.The mean value of TF_Zn was 0.91,and the maximum value of horizon scarlet was 1.42.The mean TF_Cd was 1.37 and the horizon red was the largest at 1.88.For Cu and Cd,the maximum absorption time of Cu in geranium is around 80d,while the maximum absorption time of Cd is 160d.?3?Comparing the contents,enrichment coefficients and transport coefficients of heavy metals,aboveground and underground heavy metals in plants of ten herbaceous plants,such as polygonum,it was found that ferns and compositae had strong remediation capacities for heavy metal pollution in this region.The absorption of Cr and Ni was the largest,reaching 7.92mg/kg and6.52mg/kg,respectively.The maximum absorption amount of bitter grass for As was2.01mg/kg.The absorption of the paste for Cd is the maximum,reaching 25.5mg/kg.The absorption of Pb was the highest,reaching 7.01mg/kg.The TF_Cr of artemisia annul was the largest,2.74.The TF_Ni and TF_Pb were the largest,respectively 8.35 and6.33.The TF_As of the sauce was the largest,2.16.Mint has the largest TFCd at 1.73.?4?Ratio of activated sludge to contaminated soil was 3:5,the activated sludge was the best for promoting the absorption of heavy metals As,Cd and Pb by centipede grass,the plant grew the fastest,and the content of heavy metals in soil was the lowest.The transfer of heavy metals from the aboveground part to the underground part of centipede grass was the largest,and the optimal ratio of dandelion was 1:7.