土壤有效态Cd、Cu、Pb的分布特征及影响因素研究

Soil Available Cd,Cu,Pb Distribution Characteristic and Its Influencing Factors

采集126个表层土壤样品分析了江苏省昆山市土壤有效态Cd、Cu、Pb的分布特征,并采用相关系数、通径系数和决策系数综合研究重金属有效态的含量影响因素。研究结果表明,昆山市土壤受有效态Cd、Cu和Pb的风险较大,生物有效性系数分别达63.75%,19.17%和13.51%。不同土地利用方式中交通用地的生物有效性显著高于其它各土地利用类型。随着剖面层次的下降,重金属有效态含量和生物有效性逐渐减小。土壤重金属总量对有效态均具有最大的正向影响作用,有机质对有效态含量均为较大的正向作用,FeOx含量通过吸附固持重金属离子对有效态含量也有较大负作用。

A total of 126 soil samples were collected to analyze soil available Cd, Cu, Pb distribution characteristic in Kunshan City of Jiangsu Province, and its influencing factors were studied by correlation coefficient, path coefficient and decision parameters. The results showed that Cd, Cu and Pb bioavailability reached up to 63.75%, 19.17% and 13.51%, respectively. Significant differences were observed in Cd, Cu, Pb bioavailability between different soil land use types, and available Cd, Cu, Pb were the highest in the traffic land. It was also found that the bioavailability and contents of available Cd, Cu, Pb declined with the depth in soil profile. The availability concentration of Cd, Cu, Pb were influenced by the total concentration, soil pH, content of organic matter, clay, silt, sand, CEC, FeOx and MnOx, and there were the greatest positive effect for the total concentration to the availability concentration, and also organic matter had greater positive effect, while FeOx had negative effect by adsorbing ions of heavy metals.