某铀矿下游水系沉积物剖面的放射性核素分布特征  

Radionuclides distribution characteristic in sediment profiles of a uranium smelting in Guangdong,South China

作　　者：冯颖思[1] 宋刚[1] 祝秋萍[1] 陈迪云[1] 陈永亨[1] 

机构地区：[1]广州大学环境科学与工程学院,广东省放射性核素污染控制与资源化重点实验室,珠江三角洲水质安全与保护省部共建教育部重点实验室,广东广州510006

出　　处：《中国环境科学》2013年第8期1442-1446,共5页China Environmental Science

基　　金：国家自然科学基金项目(40930743);广州大学珠江三角洲水质安全与保护实验室开放基金资助

摘　　要：为了研究广东某铀矿下游水系沉积物中放射性核素的垂直分布,利用HPGe-γ能谱仪测量了池塘底泥、溪流沉积物和水稻土剖面中238U、235U、226Ra、232Th和40K的含量.结果表明,该铀矿水系沉积物中238U、235U和226Ra污染较严重,其中池塘底泥>溪流沉积物>水稻土,而232Th和40K的变化较小.水稻土的放射性核素含量相对较低,证明稻田没有利用铀矿排放的溪水进行灌溉;而受铀矿生产影响的池塘沉积物中238U、235U和226Ra平均含量分别是水稻土的100、87和155倍,且随所采底泥样品垂直深度的增加而增高,在40cm左右含量最高.溪流沉积物中238U和226Ra含量随深度增加有小幅增加,而且238U和226Ra含量与有机质含量呈正相关.In order to study the radionuclides vertical distribution of the sediments downstream from the uranium smelting in Guangdong, the contents of 238U, 235U, 226Ra, 232Th and 40K were measured in pond sediment, river sediments, and paddy soil profiles using HPGe-7 ray spectrometer. The 238U, 23SU and 226Ra pollution were serious in the pond sediments 〉 stream sediment 〉 paddy soil, while those of232Th and40K changed a little. Radionuclides contents are relatively low in paddy soil, since the rice fields were not irrigated by water downstream from the uranium smelting. The contents of 238U, 235U and 226Ra were higher in the pond sediments than those of the paddy soil by about 100, 87, and 155 times, respectively. The contents of 238U, 235U, and 226Ra were increased with the vertical depth of sediment samples. The highest content was about 40 cm in depth. The 238U, 235U and 226Ra contents increased with stream sediment depth, and its contents positively correlated with organic matter content in the sediments.

关 键 词：铀矿 放射性核素 沉积物 垂直分布特征 

分 类 号：X131[环境科学与工程—环境科学]