放射性核素^(95)Zr在水生态系中的输运  

Migration and distribution of radioactive nuclide Zirconium-95 in the aquatic ecosystem

作　　者：赵希岳[1] 龚方红[1] 蔡志强[1] 王寿祥[2] 

机构地区：[1]江苏工业学院化学工程系,常州213016 [2]浙江大学原子核农业科学研究所,杭州310029

出　　处：《生态学报》2007年第11期4729-4735,共7页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(39970147);江苏省环境保护厅资助项目(2003076)~~

摘　　要：采用模拟污染物的同位素示踪技术研究了95Zr在水生态系中的迁移、消长和分配动态,并应用库室模型确定了各体系的拟合方程。结果表明:95Zr进入水中后,在水生态系中发生沉淀或与其他离子进行络合或被水生生物吸收或被吸附等形式在系统中迁移和转化,从而在系统各部分中分配和积累。在引入后的很短时间内,池水中95Zr的比活度迅速降至一定值后缓慢下降;底泥通过与95Zr进行离子交换,富集了大量的95Zr;水葫芦(凤眼莲)也可在短期内吸附大量的95Zr;螺蛳(环棱螺)和鲫鱼(鲫)对95Zr的吸附能力较弱,螺蛳肉中95Zr的富集率大于在壳中的富集率,95Zr在鱼体内的分布主要集中在内脏中。95Zr在系统各部分的量均受时间的影响。The dynamics of transportation, accumulation, diminishing and distribution of 95^Zr in a simulated aquatic ecosystem was studied by isotope-tracer technique, and the fitting equation was established by application of a closed fivecompartment model. The results showed that when 95^Zr was introduced into aquatic system, it was transported and transformed via depositing, complex with other ions, adsorption and absorption by aquatic living organisms, resulted in redistribution and accumulation in part of the organisms. After introduction, the specific activity of 95^Zr in the water decreased sharply to a certain value in a short time and then decreased slowly. The sediment accumulated a large amount of 95^Zr by ion exchange. The water hyacinth （Eichhornia crassipes） could also adsorb a large amount of 95^Zr in a short period of time. Snail （BeUamya purificata） and fish （ Carassius Auratus） had a poor capacity of adsorbing 95^Zr. The amount of 95^Zr in the snail flesh was greater than that in the shell, and the distribution of 95^Zr in the fish was found mainly in the viscera. The amount of 95^Zr in individual compartment of the system was affected with time. Three glass tanks with dimensions of 60cm 40cm 50cm were constructed. 8kg of paddy soil on powdery loam was filled into each pool. The tanks were flooded with 601 water. 10 ml of 95^ZrF4 with a specific activity of 4.32 × 10^5 Bq/ml was introduced into the water after one week. The water was stirred gently to get a homogeneous distribution of radionuclide. The radionuclide specific activity in water was 72.00Bq/ml. Fifteen water hyacinth （Eichhorma corssipes （Mart） Solms）, and 30 snails （Bellamya purificata ） and 15 fish （Carassius anratus ）were put into each tank. Water was added with intervals of 3 days in order to maintain a constant height of water. The samples were collected at time interval of 1,2, random collected from each pool, and disposable plastic 4, 6, 9, 15, 22, 29 and 34 days. Four 5ml aliquots of water were cups wer

关 键 词：95^Zr 水生态系统 迁移与分布 分室模型 放射生态学 

分 类 号：X132[环境科学与工程—环境科学]