95-Zr在农业生态环境中的消长动力学研究

In this study, the isotope tracer technique is used to study the dynamics of migration and distribution of 95Zr in five simulated crop ecosystem (soybean, maize, tea, cabbage and rice) and two aquatic biological (fresh water fishes and marine fishes), and its dynamics is described mathematically using a compartment model with a non-linear fitting method. The results showed that 95Zr taken up from soil mainly concentrated in roots and lower parts of stem. The radio-concentration of 95Zr in other parts of crop were relatively lower, which were only slightly greater than background level. The results indicated that 95Zr taken up from soil by crop root could not be easily transported in crop plant. More than 94% of total 95Zr in soil was retained in the upper layer (0~8cm), which indicated 95Zr could not easily move downwards because of strong adsorption to soil. Most of 95Zr concentrated in viscera, gill and fin after taken in or adsorbed by fish. The concentration of 95Zr was very low in meat, bone, liver and roe, which was only slightly greater than the detection limit. Most of adsorbed 95Zr was found in upper 2.5 cm in sediment, and more than 99% of applied 95Zr was detected in upper 2.5cm during the whole experimental period, which implied that the 95Zr in water could be adsorbed strongly by sediment and it could not readily migrate downwards with percolating water. The behaviour of 95Zr in crop ecosystem and aquatic ecosystem could be described with compartments model. The variance analysis showed that these fitting equations show consistency with experimental data. The results of these study supplies basic data and analysis in theory for science evaluate migration and accumulation status of 95Zr in environment, crop and fish, and for set down relational safety rule of law and standard.

研究核电站反应堆的主要放射性液态流出物Zr-95在农业生态环境中的迁移、输运和消长的蹋⑵湫形媛傻氖Ｐ停佣说缯驹诵泄讨信懦龅腪r-95在环境和作物中的输运和积累状况作出科学评定，为测定适合我国国情的有关标准，法规和准则提供基础数据和理论分析，缩短我国在该领域内与世界先进国家间的差距。