Ashworth D J, Shaw G
Department of Environmental Science and Technology, Imperial College London, Silwood Park, Ascot, Berkshire. SL5 7PY, UK.
Sci Total Environ. 2006 Apr 15;359(1-3):244-54. doi: 10.1016/j.scitotenv.2005.04.018. Epub 2005 May 31.
The soil solid-liquid distribution coefficient (Kd) value is of great significance in understanding and modelling the environmental behaviour of soil contaminants. For many years, the batch sorption technique has been used for the determination of such values. Here, we propose an alternative 'mini-column' approach in which somewhat more realistic soil conditions are maintained. In particular, this approach allows for determination of radionuclide Kd values under realistic soil moisture contents and in a system in which time-dependent processes such as changes in redox potential can take place. Data obtained for radioactive iodine (a key radionuclide in the consideration of radioactive waste disposal) are presented and indicate that soil moisture content, particularly in conjunction with soil redox potential (through water-logging of the soil), has a marked effect on measured Kd values. The results indicate the advantages and potential usefulness of the mini-column approach in assessing the environmental behaviour of radioactive, and other, soil contaminants.
土壤固液分配系数（Kd）值对于理解和模拟土壤污染物的环境行为具有重要意义。多年来，批量吸附技术一直用于测定此类值。在此，我们提出一种替代的“微型柱”方法，该方法能维持更接近实际的土壤条件。特别是，这种方法允许在实际土壤湿度条件下以及在一个可能发生诸如氧化还原电位变化等随时间变化过程的系统中测定放射性核素的Kd值。给出了针对放射性碘（放射性废物处置考量中的一种关键放射性核素）获得的数据，这些数据表明土壤湿度含量，尤其是与土壤氧化还原电位（通过土壤积水）相结合时，对测得的Kd值有显著影响。结果表明了微型柱方法在评估放射性及其他土壤污染物的环境行为方面的优势和潜在用途。
