Effects Of Charcoal And Ferrous Sulphate On Uptake Of Heavy Metals In Rice The Lead-zinc Mining Area

Mining activities are an important source of pollution of heavy metal pollution in the soil.Pollutants generated during the mining process enter the surrounding soil through various means,and produce heavy metal pollution to the surrounding farmland.For farms with low levels of pollution,we can reduce the absorption of heavy metals by crops by changing the farming system and produce low-polluted farms to produce foods that meet food standards.In this paper,the surrounding farmland of a lead-zinc mine in Anhui Province was selected as the research object,and the crops produced in the surrounding areas of the lead-zinc mine and the farmland were collected and collected.The crops and the crops produced in the surrounding areas were investigated.The effects of the application of charcoal and ferrous sulphate on the accumulation of heavy metals in rice were studied.The effects of ferrous sulphate on the formation of iron film from rice root surface were studied in detail.The results showed that the addition of charcoal and ferrous sulphate to the accumulation of heavy metals in rice was studied.Its effect on the absorption of copper and zinc in rice.To provide theoretical and practical help for the safe production of rice in the region.The main findings are as follows:(1)The results showed that the content of Zn in the surrounding farmland of the lead-zinc mine was 162.49-488.03 mg / kg and the coefficient of variation was 26.7%.The content of As in the range of 39.95-100.73 mg / Kg,the coefficient of variation was 23.96%.The content of Cd was 0.35-1.88 mg / kg and the coefficient of variation was 37.84%.The average contents of Zn,As and Cd all exceeded the secondary standard of national soil environmental quality.The average content of As in rice and wheat in the surrounding farmland was 0.48 mg / kg and 0.49 mg / kg,all exceeding the national food safety standard.(2)The pot experiment was conducted to study the difference of heavy metal accumulation in different varieties of rice.The results showed that the content of Cd in rice was 0.03-0.13 mg / kg,the highest and lowest values were 4 times;Zn content was 22.41-39.59 mg / kg,the highest and lowest values were less than 1 times;Pb content was 0.05-0.17 mg / kg,the highest and the lowest difference of 3 times;As content of 0.25-0.41 mg / kg,the highest and lowest value difference of less than 1 times.(3)The formation of iron film on root surface of rice was induced by the addition of ferrous sulfate under hydroponic conditions.The solution of DCB(sodium dithionite-sodium bicarbonate-sodium citrate),scanning electron microscopy,energy dispersive spectrometer and X-ray diffraction The results show that the addition of ferrous sulphate can induce a large number of root iron films to be produced on the surface of rice roots,and the results are shown in Fig.Sodium dithionite-sodium bicarbonate-sodium citrate)solution and scanning electron microscopy(SEM)can be used to detect the Fe content of DCB extract in untreated rice root table with 731 mg / kg Fe and 80 mg / kgFe2 + The content was 53562 mg / kg.Compared with the untreated rice,the content of Cu in the root film increased by 73.16% and the Zn content increased by 112.10%,the highest Cu content was reduced by 31.15% and the Zn content was 13.02% lower than that of untreated rice.The content of Cu in stems and leaves decreased by 19.50% and Zn content was 25.56%.(4)The effects of charcoal and ferrous sulphate on the uptake of arsenic,zinc and cadmium were studied by pot experiment and field experiment.The soil pH,soil heavy metal morphology,rice yield and heavy metal content of rice were measured under different treatment groups.The results showed that the application of charcoal and ferrous sulphate could promote the growth and development of rice and increase the yield and biomass of rice.It was found that adding charcoal could increase the pH of soil,and the addition of charcoal could significantly reduce the extraction of Cd and Zn in soil Down by 36.17% and 23.61%.The contents of Cd and Zn in brown rice were decreased by 67.91% and 27.19%,respectively.The Cd and As of brown rice were 54.84% and 33.33% lower than that of CK.The addition of ferrous sulfate Rice Cd and As decreased by 22.58% and 66.67% compared with CK.