Knowledge of the chemical forms and binding types of metals enables evaluation of their behavior and bioavailability in soil. This study employed a combination of sequential extraction and X-ray absorption spectroscopic analyses to examine the speciation of As, Pb, and Cd in soils from the mine tailing area of the abandoned Kamegai mine in Japan. The results revealed that most As was As(V) and was adsorbed primarily on goethite and secondarily on ferrihydrite formed by the oxidation of sulfide ores in the tailings. Most Pb was also adsorbed onto goethite, although the desorption behaviors of Pb and As differed. Cadmium, however, was adsorbed onto clay minerals in the soils around the mine tailings. The different mobility of Cd versus As and Pb was possibly related to its lower adsorption affinity to iron oxides but higher affinity to roots of the fern Athyrium yokoscense. River water in this area, which is characterized by slightly basic pH and very low electric conductivity, exhibited concentrations of As exceeding 10 μg/L but low concentrations of Pb and Cd. The difference of the solubilities of the heavy metals could be explained by river water chemistry and metal speciation.

中文翻译：

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历史采矿场污染土壤中铅，砷和镉的化学形态比较：对不同重金属迁移率的影响

了解金属的化学形式和结合类型可以评估其在土壤中的行为和生物利用度。这项研究采用顺序萃取和X射线吸收光谱分析相结合的方法，研究了日本Kamegai废弃矿山尾矿区土壤中As，Pb和Cd的形态。结果表明，大多数As是As（V），主要吸附在针铁矿上，其次吸附在尾矿中硫化矿石氧化形成的三水铁矿上。尽管Pb和As的解吸行为不同，但大多数Pb也被吸附到针铁矿上。然而，镉被吸附到矿山尾矿周围土壤中的粘土矿物上。Athyrium横须贺。该地区的河水的特点是pH值基本为碱性，电导率非常低，其As的浓度超过10μg/ L，但Pb和Cd的浓度较低。重金属溶解度的差异可以用河水化学和金属形态来解释。