工矿型绿洲农田土壤中氟和镉的剖面行为研究

以甘肃白银市城郊东区农田土壤为研究对象进行剖面取样、对土壤中氟和镉的剖面分布及行为进行研究.结果表明,在长期灌溉与降水渗水流作用下,F和Cd发生不同程度的淋溶迁移,F迁移深度达到80~100cm,Cd迁移深度在40~60cm,迁移程度为F>Cd;元素F和Cd都具有显著的负乘幂迁移规律,同时表现出不同的迁移态势,F 为高剂量时迁移率大,低剂量时迁移率小,但Cd呈现相反的迁移趋势.污水灌溉作为土壤污染物来源之一对土壤F和Cd累积和迁移有一定影响,F元素对当地地下水污染的威胁较大.

Vertical distribution and behavior of fluoride and cadmium in the wastewater irrigated agricultural land of industrial oasis region,Northwest China

Distribution and behavior of fluoride (F) and cadmium (Cd) in cultivated soil profile from suburban oasis soils in baiyin city irrigated with waster water for a long time was investigated. Results showed that there had the different levels of leaching transport for different elements under the influence of infiltration of irrigation or precipitation, and the order of element transport levels was F>Cd, the migration depth of F reached to 80~100cm, the migration depth of Cd reached to 40~60 cm; the significant model of negative power function were both found for F and Cd to explain the heavy metal transfer in soil profile, while F and Cd showed different migration behavior that F had high mobility with large dose, but Cd exerted opposite effects. As a source of soil pollutants, wastewater irrigation could make difference on accumulation and mobility of F and Cd, and F may pose a threat to groundwater.