Features and factors of radium isotopes in Tianjin’s typical estuaries  

作　　者：Zhe Zhang Yingchun Dong Lixin Yi Xin Hao Yajie Zheng Tianxue Lü 

机构地区：[1]College of Environmental Science and Engineering,Nankai University,Tianjin 300350,China

出　　处：《Acta Oceanologica Sinica》2023年第8期134-146,共13页海洋学报（英文版）

基　　金：The National Natural Science Foundation of China under contract No.42172273.

摘　　要：In order to characterize the features of radium isotopes in estuaries of Tianjin,a continuous survey and sampling of typical estuaries were conducted from 2013 to 2017 in this study.The activities of natural radioactive radium isotopes(^(223)Ra,^(224)Ra,and ^(228)Ra)in groundwater and surface water were measured by the radium-delayed coincidence counting(RaDeCC)system.The non-conservative behavior of the radium isotopes was investigated under hydrogeochemical conditions and urbanization.The results indicated that in terms of horizontal distribution,the activities of radium in groundwater(Hangu,Tanggu,and Dagang)showed an upward trend from north to south and demonstrated a higher figure than surface water(Haihe River and Duliujian River).Concerning the vertical distribution,the activitives of radium at a 15 m burial depth was higher than that at a 30 m burial depth in all measurements.The activities of radium isotopes in the study area increased with the increase of total dissolved solids,and their desorption behavior on Fe-Mn oxides was constrained by the redox intensity.Different hydrogeological conditions resulted in variations in the vertical profile of radium activities.The activity of radium was regulated by seasonal variation and precipitation in groundwater and surface water.In addition,the rapid urbanization has caused a significant impact on the features of radium isotopes in typical estuaries of Tianjin.Meanwhile,radium isotopes can be applied to reflect the impact of urbanization on surface watergroundwater systems.Clarifying and cleverly utilizing the relationship between behavior of radium isotopes and urbanization will promote the development of the Tianjin Binhai New Area in a healthy way.

关 键 词：ESTUARY radium isotope total dissolved solids ionic strength URBANIZATION 

分 类 号：X14[环境科学与工程—环境科学] P73[天文地球—海洋科学] P641.2