土壤中Pb离子地球化学行为模拟实验--以山西的典型土壤为例  

Simulation experiment of the geochemical behavior of Pb in soils—A case study of typical soils in Shanxi,China

作　　者：李艳艳[1] 王亚平[1] 周继华 王建武 许春雪[1] 王苏明[1] 

机构地区：[1]国家地质实验测试中心,北京100037 [2]山西店地质调查院,山西太原030001

出　　处：《地质通报》2008年第2期230-239,共10页Geological Bulletin of China

基　　金：中国地质调查局《山西省多目标生态农业地球化学调查》项目(编号:200314200019)资助

摘　　要：土壤样品分别采于山西省大同、太原和临汾3个地区。实验分成吸附解吸、竞争吸附和运移实验3个部分。其中吸附实验分成砂粒土壤和粘粒土壤2个粒级分别进行。结果表明:在常温常压下,Hery模式更适合描述3种土样砂粒部分和粉粘粒部分对Pb2+的吸附。吸附实验结果表明,土壤对Pb有很强的吸附作用,吸附过程受CEC的影响很大。在竞争吸附实验中,Pb的存在减少了土壤对Cd的吸收;腐殖酸对土壤吸附Pb2+表现出抑制作用。解吸实验结果表明,Pb在土壤中以专性吸附为主,吸附的Pb很难解吸下来。运移实验结果显示,在长达20天的淋滤过程中Pb2+仍没有穿透土柱,说明土壤对Pb2+的吸附能力极强,Pb迁移非常缓慢。Soil samples were taken from Datong, Taiyuan and Linfen. The experiment comprised three parts： adsorption-desorption, competitive adsorption and transport experiment. Soils for the adsorption experiment were sieved into the sand-sized fraction and clay-sized fraction. The main results indicate that at normal temperature and press the Hery model is more suitable for depicting the adsorption of Pb^2＋ by the sand-sized fraction and silt- and clay-sized fraction of the three types of soil. The adsorption experiment shows that soils have a very strong adsorption capacity and that CEC has an obvious effect on the adsorption process. In the competitive adsorption experiment, the presence of Pb reduces the adsorption of Cd by soils and humic acid can inhibit the adsorption of Cd by soils. The experiment of desorption shows that Pb in soils is mainly absorbed and is very difficult to desorb. The transport experiment indicates that after 20 days of leaching Pb^2＋ still failed to penetrate through the soil column, which suggests that soils have a very high capacity of Pb^2＋adsorption and that Pb was transported very slowly.

关 键 词：土壤 Pb离子的地球化学行为 吸附-解吸-运移 模拟实验 

分 类 号：P595[天文地球—地球化学] S151.93[天文地球—地质学]