摘要
本文通过对黄海表层沉积物中总β放射性的分析测定,对黄海环境放射性污染现状进行了初步评价。结合沉积物类型、沉积环境等因素的宏观状况,初步探讨了黄海沉积物中总β放射性的分布特征。总β放射性与沉积物的粒度、碳酸盐含量、Eh值及Fe^(3+)/Fe^(2+)值存在一定的负相关关系,与沉积物的有机质及自生黄铁矿的含量存在一定的正相关关系。海洋沉积物放射性调查必须同时考虑沉积物的类型、沉积物化学特征及海洋动力状况诸因素。
In this paper,the sea area of interest is the Huanghai Sea north of 34°30′N,west of 124°E.120 sampling stations were set principally at grid points and the surface layer sediments in the upper 5 cm were sampled.The total beta measurement and energy spectrum analysis are made with PJ-332 low background beta counter and FH-1906 low background Nal(T1)gamma-ray spectrometer,respectively.The total beta radioactivity in sediment and its distribution are then discussed comprehensively in conjunction with the sediment type,the chemical characteristics of sediment and the dynamical conditions in the sea.The content of total beta radioactivity in surface layer sediment in the Huanghai Sea ranges from 9 to 45nCi/kg(dry weight)with a mean of 24nCi/kg(dry weight).The total beta radioactivity varies with the sea area,the higher content area are the southern Huanghai Sea,the underwater plain in the northern Huanghai Sea,the former Huanghe River Delta and the sea area off Changshan Islands,whereas the lower content areas are the Haizhou Bay residual deposit area and the Bohai Strait residual deposit area.The radioactive isotopes in the sediments are basically the natural radioactive isotopes of U,Th family and ^(40)K etc.The total beta radioactivity content in the sediment exhibits certain negative correlations with the grain size of sediment,carbonate content,Eh value and Fe^(3+)/Fe^(2+)value in the sediment,and certain positive correlations with the organic matter and authigenic pyrite content in the sediment.The above-mentioned factors interact with each other,and the correlation is consistent with the interaction among the abovementioned factors.Therefore,the sediment type,the chemical characteristics of the sediment and the dynamical condition in the sea should be taken into account in investigation on marine sediment radioactivity.
作者
尹毅
Yin Yi(First Institute of Oceanography,NBO,Qingdao)
出处
《海洋与湖沼》
1985年第5期371-379,共9页
Oceanologia Et Limnologia Sinica
