乙酸-乙酸钾缓冲溶液对苜蓿草吸收土壤中铬离子的影响研究

采用室内盆栽试验和BCR优化连续萃取法,研究了不同pH值乙酸-乙酸钾缓冲溶液对混合污染土壤中重金属铬的形态变化及紫花苜蓿吸收土壤中铬离子的影响。结果表明:乙酸-乙酸钾缓冲溶液对土壤中铬离子由非有效态转化为有效态的作用显著;并且有效提高了苜蓿草对土壤中重金属铬离子的吸收;不同pH值的乙酸-乙酸钾溶液对苜蓿草吸收土壤中铬离子的影响效果也有差异。在试验范围内,溶液pH为5.8的乙酸-乙酸钾缓冲剂对苜蓿草吸收重金属的影响效果最佳,此时,苜蓿草对铬离子的富集量达到37.55mg/kg,富集系数达到0.22;与对照相比提高近3倍。

Study of Influence on Remediation of Chromium in the Soil by Alfalfa Under the Acetic Acid-Potassium Acetate Buffer Solution

A pot experiment and the sequential extraction procedure of the optimized European Community Bureau of Reference(BCR) were conducted to investigate the absorption of chromium by alfalfa and the redistribution of fractions under different pH Acetic acid-Potassium acetate buffer solution.The results showed that soil chromium ion from its inactive state into effective state effect and the migration ability of chromium from soil to plant were notable promoted with adding Acetic acid-Potassium acetate solution to the soil.The migration ability of chromium ion from soil to plant was also different under different pH Acetic acid-Potassium acetate buffer solution.In the test range,the accumulation of chromium from soil to plant were a control sample of 3 times when the pH was 5.8,the content value was 37.55 mg/kg,the enrichment coefficient reached 0.22.