【摘要】 利用放射性同位素研究土壤中离子的扩散,早有文献报道,这在测定方法上是一个很大的改进。近年来,利用放射性同位素¹³¹I 和³⁵S 模拟土体和地下水盐分运行的一些规律,揭示了表土积盐的过程;利用放射性同位素 ²²Na 研究原状土柱盐化和脱盐化过程中钠的上下运动规律;利用放射性同位素示踪方法研究土壤中盐分移动和表土积盐规律,这些无疑是很方便很有效的手段。本文仅就核素在实验土柱中扩散问题加以讨论。更多还原

【Abstract】 Radioisotope tracers have been used for studying the movement and accu- mulation of salt in surface soil.This study indicates that ²²Na added to surface layer of experimental soil column decreases by 18.4% for the first hour and 75.0% for the eighteenth hour due to downward diffusion,while ¹³¹I and ⁶⁰Co added to surface layer decrease by 59.9% and 25.6% respectively at the 30th hour.Besides,it indicates that the radioisotopes in experimental soil column also diffuse in opposite direction.The rate of diffusion is correlated with the physical property of the surface layer of experimental soil column.更多还原