Ashworth D J, Shaw G, Butler A P, Ciciani L
Department of Environmental Science and Technology, Imperial College of Science Technology and Medicine, Silwood Park, Ascot, Berkshire SL5 7PY, UK.
J Environ Radioact. 2003;70(1-2):99-114. doi: 10.1016/S0265-931X(03)00121-8.
This paper describes a 12-month experiment designed to study the extent of upward migration of (125)I (as a surrogate for (129)I) from near-surface groundwater, through a 50-cm column of soil and into perennial ryegrass. The water table was established at a depth of 45 cm below the soil surface. By 3 months, (125)I had migrated about half way up the soil column. After this, it tended to accumulate just above this mid-point, with only very small amounts being transported to the upper 20 cm of soil. This behaviour seemed to be explained well by soil moisture and redox conditions. The experiment indicated that (125)I was mobile only within the saturated/low redox zone at the base of the soil column and accumulated in the zone of transition between anoxic and oxic soil conditions. Uptake of (125)I by the ryegrass was found to be low.
本文描述了一项为期12个月的实验，该实验旨在研究（125）I（作为（129）I的替代物）从近地表地下水向上迁移，通过50厘米厚的土壤柱并进入多年生黑麦草的程度。地下水位设定在土壤表面以下45厘米深处。到3个月时，（125）I已迁移至土壤柱大约一半的高度。在此之后，它倾向于在这个中点上方积累，只有极少量被运输到土壤上部20厘米处。这种行为似乎可以通过土壤湿度和氧化还原条件得到很好的解释。实验表明，（125）I仅在土壤柱底部的饱和/低氧化还原区内具有流动性，并在缺氧和有氧土壤条件的过渡区内积累。发现多年生黑麦草对（125）I的吸收较低。
