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The Changjiang River is the third longest river in the world,the longest river in China.It has a drainage area of about l.8 million square kilometers.Because of the fallout of nuclear tests and the discharge of some NORM industries,concentrations of artificial and natural radionuclides in the Changjiang River are quite different as the spatiotemporal distribution.The concentration data of artificial radionuclides 90Sr and 137Cs and natural radionuclides 40K,226Ra,U,Th,3H,2IOPo and 2IOPb in the Changjiang River system are collected since 1965.The data cover surveys on the radioactive level in the Changjiang River System in 1980s,monitoring radioactive levels of state controlling sections over the last decade,and measuring concentrations of radionuclides in some regions.The statistics result over these years shows,affected by nuclear tests in northwest China,the concentrations of 3H,90Sr and 137Cs are relatively high from 1960s t0 1970s,and then begin to continuously decrease year by year,and go stable close to background level from late 1970s.There is a rise for the concentration data of 137Cs in 1986,which may be affected by the release of Chernobyl accident.Before 2000,the average level of concentration of natural radionuclides 40K,226Ra,U and Th do not display obvious difference,nevertheless the monitoring data of state controlling sections in these years are changing in a large extent.In some area,some concentrations are very high,which are mainly influenced by the discharge of some NORM industries.