长江口放射性核素Pu的大气湿沉降初步研究  

Atmospheric Wet Deposition of Radionuclide Pu in the Changjiang River Estuary Region

作　　者：张克新[1] 潘少明[1] 徐仪红[1] 曹立国[1] 徐伟[1] 张威[1] 郝永佩[1] 

机构地区：[1]南京大学地理与海洋科学学院海岸与海岛开发教育部重点实验室,江苏南京210023

出　　处：《地理科学》2016年第1期157-160,共4页Scientia Geographica Sinica

基　　金：国家自然科学基金项目(41271289;41230751)资助~~

摘　　要：利用东京239,240Pu的年沉降和年降水数据,对长江口地区1957~2005年239,240Pu的年大气湿沉降通量进行研究。结果表明：长江口地区1957~2005年间239,240Pu的大气湿沉降量在0.001 2~5.531 Bq/m2之间,累计湿沉降通量为34.556Bq/m2;该地区Pu的大气湿沉降主要集中在1960 s;1960 s初频繁的大气核试验是造成239,240Pu在1960 s沉降量较大的主要原因。长江口地区与东京地区239,240Pu大气沉降变化基本一致,两地的大气湿沉降均在1963年出现明显峰值。Anthropogenic radionuclides（137Cs,90 Sr, and Pu isotopes） released from atmospheric nuclear tests, major nuclear reactor accidents, and other sources can be detected in the environment in most parts of the world. In particular, as a result of atmospheric nuclear explosions, about 15 PBq of239,240Pu（1 PBq=1015Bq） and 0.3 PBq of238 Pu have been globally released into the atmosphere. These radionuclides may be useful tracers of environmental changes, such as desertification, erosion and sedimentation processes, in terrestrial regions. Furthermore, measurements of radionuclide deposition are useful for several purposes, including the assessment of the effects of radiation from anthropogenic radionuclides on humans. They may also find use as indicators of environmental events. Most of the current investigations focus on the chemical behaviors such as transfer and diffusion in environment, but for the atmospheric wet deposition of radionuclide Pu, the publically available report is very limited in China. In this article, we investigated and quantified preliminarily the239,240 Pu atmospheric deposition in the Changjiang River Estuary Region based on the records of239,240 Pu atmospheric deposition and precipitation in Tokyo in Japan. The results indicated that239,240 Pu atmospheric deposition history in the Changjiang River Estuary Region was similar to that of the whole north hemisphere. The cumulative atmospheric deposition inventory of239,240 Pu was estimated to be 34.556 Bq/m2 in 1957-2005. The maximum annual deposition occurred in 1963 after the large-scale atmospheric nuclear weapons testing in 1950s-1960 s conducted by the United States and former USSR. Annual239,240 Pu deposition decreased in the period from 1963 to 1967 according to the stratospheric residence time of nuclear debris. In the 1970 s, the radionuclide deposition observed in the Changjiang River Estuary showed no decrease because of a series of American and Chinese atmospheric nuclear tests. In addition,239,240 Pu atmospheric deposition hist

关 键 词：放射性核素 大气沉降 PU 长江口 

分 类 号：P734[天文地球—海洋化学]