【摘要】 本文介绍在1983—1990年间国家环境保护局组织的以全面摸清我国环境天然放射性现状水平、分布及其规律为主要目的的全国环境天然放射性水平调查的结果和方法的概要。在全国960万km²。面积上（不包括台湾省）,基本以25×25km 网格均匀布点调查了环境陆地γ辐射剂量率（分原野γ辐射剂量率 D_原,道路γ辐射剂量率 D_道和室内γ辐射剂量率 D_室;均指离地面1m 高处的空气吸收剂量率）;与此同位布点,同时采集土壤样品,调查了土壤中²³⁸U、²²⁶Ra、²³²Th 和⁴⁰K 含量;还与非放射性监测同位布点调查了各类水体中的 U、²²⁶Ra、Th 和⁴⁰K 浓度。并在核企业和可能发生人为污染的地区周围作了加密布点调查。调查所得主要结果如下:（1）按全国8805个网格点统计的 D_原按面积、按人口加权均值分别为62.8、62.1nGy/h。（2）D_道按网格点加权均值为61.8nGy/h,道路和原野γ辐射剂量率比值的平均值（?）0.98。（3）D_室按人口加权的均值为99.1nGy/h,（?）=1.64。（4）宇宙射线电离成分所致空气吸收剂量率按点和按人口加权均值,室外分别为39.9和32.5nGy/h,室内分别为35.4和28.5nGy/h。（5）天然γ辐射和宇宙射线所致我国居民人均年有效剂量当量分别为0.55和0.26mSv。（6）按7777个网格点统计的全国土壤中（干样）²³⁸U、²²⁶R更多还原

【Abstract】 This paper gives an overview of the results and methods presented in the Nationwidesurvey of Environmental Radioactivity Level in China organized by The National Environment Protec-tion Agency during a time period from 1983 through to 1990 with the main aim of ascertaining thecurrent level,distribution and pattern of radioactivity in China.Through the distribution of the measur-ing points over the area（without Taiwan Province）of the country basically using the grid size of 25×25kin in sampling network,environmental gamma terrestrial radiation dose rates were investigated,in-cluding field gamma radiation dose rate,D_f,road gamma radiation dose rate,D_r,and indoor gamma radiation dose rate,D_in,which all refers to absorbed dose rate in air 1 m above ground.At the same time and,at the same points,soil samples were also collected to survey the contents of²³²Th,²³⁸U,²²⁶Ra and ⁴⁰K in soil and,at the same Ideations as previously used in nonradioaetivity sur-vey,the concentrations of Th,U,²²⁶Ra and ⁴⁰K in waters of different types were investigated.As wellaround the offsite areas surrounding nuclear industries and the possible areas where artificially imposedradioactive contamination would appear,investigation was conducted by adding points densely.The main results aehieved in the survey are as follows:1)acording to the nationwide statistical data from 8805 grid points all over the country,the area-weighted and population-weighted average values of field gamma radiation dose rate are 62.8and 62.1nGy·h^-1respeetively;2)grid point-weighted average value for road gamma radiation dose rate is 61.8nGy·h^-1and theaverage value of the ratio of D_r to D_f is 0.98;3)population-weighted average values for indoor gamma radiation dose rate is 99.1nGy·h^-1andthe average value of the ratio of D_into D_f is 1.64;4)the point-weighted and population-weighted average values for radiation dose rate due to cos-mic ray ionizing component excluding neutron component are 39.9 and 32.5 nGy·h^-1out-doors and 35.4 and 28.5nGy·h^-1indoors respectively;5)per capita annual effective dose quivalents to our population from natural gamma radiation andcosmic rays are 0.55 and 0.26mSv respectively;6)area-weighted average values of the contents of ²³²Th,²³⁸U,²²⁶Ra,and ⁴⁰K in the soil（dryedsamples）from 7777grid points all over the country are 49.1,39.5,36.5,and 580.0Bq·kg^-1respectively;gamma radiation dos rate in air lm above ground calculated using the Beckformula and assuming water content rate of 10% is 65.7nGy·h^-1,which is 5% higher thanthe measured result;7)for the concentrations of U,Th,²²⁶Ra and ⁴⁰K in river,lake,reservoir,offishore water,spring,and well and tap water,as collated and collated according to 6611 samples from 4021 points,the value for U is in the order of magnitude of μg·L^-1,except in case of saltwater lake;thevalue for Th is of the order of magnitude of 10^-1μg·L^-1;the value for ²²⁶Ra is of the order ofmagnitude of mBq·L^-1except for hot spring;and the value for ⁴⁰K range from 60 to 200 mBq·L^-1except in case of sea,saltwater lake and hot spring.Through this survey,useful baseline data for the nomitoring and manasement of the environmen-tal radioaetivity in our country have been gained.Among them some will be of value to the researchworks in aspects of geology,radioecology and building materials.更多还原