氯化钠和醋酸钙镁两种融雪剂对土壤中典型重金属结合态的影响

采用实验室模拟方法, 分别用氯化钠（NaCl）和醋酸钙镁（CMA）两种常见的融雪剂液浸泡和淋溶土壤, 并用Tessier连续萃取法测定土壤中Zn和Cu两种重金属各结合态质量比的变化, 考察两种融雪剂对土壤中典型重金属结合态的影响. 结果表明： NaCl融雪剂比CMA融雪剂对土壤重金属影响更明显, 且NaCl的浓度越高差别越大； 土壤中的Zn和Cu在融雪剂浸泡作用下都倾向于转化为可交换态, 可交换态Zn最多增加115%； 融雪剂淋溶作用对Zn结合态影响较大, 其可交换态、 碳酸盐结合态Zn比蒸馏水淋溶分别降低了30%，20%； 对Cu结合态影响较小； 两种金属的有机/硫化物结合态和残渣态受融雪剂浸泡和淋溶的影响均很小； CMA比NaCl融雪剂对环境更友好.

Effects of NaCl and CMA Deicing Salts onBinding States of Typical Heavy Metals in Soil#br#

Using laboratory simulation method, soil was soaked andleached with sodium chloride (NaCl) and calcium magnesium acetate (CMA), respectively, we determined the variation of mass ratio of binding states of Zn and Cu in soil by Tessier sequential extraction procedure, and investigated the effects of two deicing salts on bindingstates of typical heavy metals in soil. The results show that NaCl has more obvious effect on heavy metals in soil than CMA,and the higher the concentration of NaCl, the greater the difference.Both Zn and Cu in soil tend to be converted into exchangeable state under the action of immersion of deicing salts, and exchangeable state of Zn increases by 115% at most. The leaching effectof deicing salts has a great effect on binding state of Zn,compared with distilled water leaching, the exchangeable and carbonatestates of Zn are reduceed by 30% and 20%, respectively, the effect on binding state of Cu isminor. The organic/sulfide binding state and residual state of Zn and Cu are little affected by immersion and leaching of deicing salts.CMA is more environment friendly than NaCl deicing salts.