Fortunati P, Brambilla M, Speroni F, Carini F
Università Cattolica del Sacro Cuore, Faculty of Agricultural Sciences, Agricultural and Environmental Chemistry Institute, Soil Chemistry Section Via Emilia Parmense 84, I-29100 Piacenza, Italy.
J Environ Radioact. 2004;71(2):187-99. doi: 10.1016/S0265-931X(03)00168-1.
In this paper a study of the foliar uptake and translocation of 134Cs and 85Sr in a herbaceous fruit plant is presented. In particular, absorption, translocation and loss of these radionuclides in strawberry plants have been studied in relation to the age of contaminated leaves. Strawberry plants were contaminated by distributing droplets of an aqueous solution containing 134CsCl and 85SrCl2 on the surface of two leaves per plant. One half of the plants was contaminated through two young leaves, a second half through two old leaves. Sets of plants were collected 1 day, 7 days and 15 days after contamination. One half of them was rinsed with double distilled water before gamma analysis. Rinsing contaminated leaves removes on average 55% of the applied 134Cs and 45% of 85Sr. The activity removed decreases during the 15 days of the experimental study, both for 134Cs and for 85Sr, suggesting an increase in foliar absorption during this period. The activity removed does not differ between old and young leaves. "External loss" is lower for young than old contaminated leaves. "Internal loss" through translocation occurs mainly for 134Cs. Translocation coefficients from contaminated leaves to fruits are two orders of magnitude higher for 134Cs (4.0%), than for 85Sr (0.05%). Leaf to fruit translocation coefficients for 134Cs are higher from young leaves (5.8%), than from old leaves (2.3%).
本文介绍了一项关于草本果树植物中¹³⁴Cs和⁸⁵Sr的叶部吸收与转运的研究。具体而言，针对草莓植株中这些放射性核素的吸收、转运和损失与受污染叶片年龄的关系进行了研究。通过将含有¹³⁴CsCl和⁸⁵SrCl₂的水溶液滴洒在每株植物的两片叶子表面来污染草莓植株。其中一半植株通过两片幼叶进行污染，另一半通过两片老叶进行污染。在污染后1天、7天和15天收集植株样本。其中一半在进行伽马分析前用双蒸水冲洗。冲洗受污染叶片平均可去除所施加¹³⁴Cs的55%和⁸⁵Sr的45%。在为期15天的实验研究期间，¹³⁴Cs和⁸⁵Sr被去除的活度均下降，这表明在此期间叶部吸收增加。老叶和幼叶被去除的活度没有差异。幼龄受污染叶片的“外部损失”低于老龄受污染叶片。通过转运造成的“内部损失”主要发生在¹³⁴Cs上。¹³⁴Cs从受污染叶片到果实的转运系数（4.0%）比⁸⁵Sr（0.05%）高两个数量级。¹³⁴Cs从幼叶到果实的叶果转运系数（5.8%）高于老叶（2.3%）。
