^(95)Zr在茶叶土壤系统中的迁移与分布动态  

DYNAMICS OF TRANSFERENCE AND DISTRIBUTION OF ^(95)Zr IN THE TEA-SOIL ECOSYSTEM

作　　者：史建君[1] 

机构地区：[1]浙江大学原子核农业科学研究所农业部核农学重点开放试验室,浙江杭州310029

出　　处：《核农学报》2002年第6期382-386,共5页Journal of Nuclear Agricultural Sciences

基　　金：国家自然科学基金资助项目 (批准号 :39970 14 7)

摘　　要：采用模拟污染物的同位素示踪技术进行了95Zr在茶树 土壤系统中的迁移与分布动态研究 ,并应用库室模型和非线性回归方法确定了各分室的拟合方程。结果显示 :1 茶树从土壤中吸收的95Zr主要集中在茎秆中 ,且茎秆中的95Zr比活度随时间呈缓慢增加 ,并在一段时间后逐渐趋于动态平衡 ;其余各部位的比活度较低 ,大部分接近于本底水平 ,表明95Zr被茶树茎皮部吸收后不易在其体内迁移、输运 ;2 喷施进入土壤中的95Zr主要滞留在表层 ( 1～ 5cm)土壤中 ,占总量的 98 9% ,表明95Zr被表层土壤吸附 ,不易随渗流水向下迁移 ;3 对实验数据进行回归分析 ,得茶树和土壤中95Zr比活度的消长动态拟合方程分别为Ct(t) =9 2 3 60 ( 1 -e- 0 14 59t)和Cs(t) =486 84( 0 1 4 58-0 0 0 0 0 82e- 0 14 59t) ,经方差分析 ,表明回归方程较好地反应了95Zr在茶树 土壤系统中的消长动态。The dynamics of transference and distribution of 95 Zr in the tea soil ecosystem were studied by using isotope tracer techniques for simulated pollutants from nuclear power plant, and the fitting equation was confirmed by application of the closed tow compartment system model and nonlinear regression method. The results showed as follows.1.The 95 Zr absorbed from soil mainly retained in the stem of tea plant, and the specific activity of 95 Zr in stem increased with time slowly, then reached a dynamics balance gradually after a period of time. The specific activity of rest parts was lower, and most parts were in the level of background activity, which indicated that the 95 Zr absorbed by the bark of tea was difficult to transfer to other parts of the tea; 2 The 95 Zr in soil deposited mainly(98\^7%) in surface layer soil(1～5cm), indicating that the 95 Zr absorbed by surface soil wasn't downflow with water current easily; 3 The regression equation of accumulation and disappearance of 95 Zr in the tea and soil were C t(t) =9 2360(1-e -0 1459t ) and C s(t) =486 84(0 1458-0 000082e -0 1459t ) by analyzing the experiment data with exponential regression method. The results of squared deviations indicated that each regression equation could described the dynamics of accumulation and disappearance of 95 Zr in the tea soil ecosystems preferably.

关 键 词：^95ZR 茶叶-土壤系统 迁移 分布动态 茶树 放射生态学 非线性回归 

分 类 号：X131.3[环境科学与工程—环境科学]