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应用放射性同位素示踪技术研究了１２５Ⅰ在农业生态系统中的行为，包括水稻对１２５Ⅰ的吸收、运输、分配；１２５Ⅰ在土壤中的迁移和水生植物对１２５Ⅰ的吸收、运转、分配，并计算出１２５Ⅰ在土壤中的垂直分布和１２５Ⅰ在水生生态系统中动态变化的数学模型．结果表明：水稻能吸收１２５Ⅰ，并可将吸收到的一半以上运转至地上部；成熟期谷粒中１２５Ⅰ的积累量最低，仅占全株的０１８％；１２５Ⅰ在土柱中迁移２７ｄ后，大部分分布在表层，分布随深度而呈指数规律递减；供试的４种水生植物中，矮慈菇（ＳａｇｉｔａｒｉａｐｙｇｍａｅａＭｉｑ．）对水体中１２５Ⅰ吸收最快，富集系数最大，到试验结束时达８５７９，可用来净化水体中１２５Ⅰ的污染，１２５Ⅰ在水生生态系统中的动态变化符合ｙ＝Ａｅｂｔ变化规律．
The radioactive isotope tracing technique was used to study the behavior of 125 Ⅰ in agroecosystem, including the uptake, transport and distribution of 125 Ⅰ in rice, 125 I in soil and 125 I absorption, transport and distribution by hydrophytes, and 125 I Vertical Distribution in Soil and Mathematical Model of Dynamic Change of 125 I in Aquatic Ecosystems. The results showed that rice could absorb 125 I, and could transfer more than half of the uptake to aboveground part. The accumulation of 125 I in mature grain was the lowest, accounting for only 0.18% of the whole plant. After 125 days of 125 I in soil column, , Most of which distributed on the surface and the distribution decreased exponentially with depth. Of the four aquatic plants tested, Sagitaria pygmaea Miq. Had the fastest absorption and the highest enrichment coefficient for 125 I in water, reaching to the end of the experiment 85 79, can be used to purify 125 I pollution in water, 125 I dynamic changes in aquatic ecosystems in line with y = Aebt variation.