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海洋学报:英文版 2023年第8期42卷 24-31页

作者： Hequan Gu Feng Zhao Zhixin Ni Meigui Wu Li Zhao Aicui Dang Dongmei Li Minxia Zhang Qin Hu South China Sea Environment Monitoring Center State Oceanic AdministrationGuangzhou 510300China Nansha Islands Coral Reef Ecosystem National Observation and Research Station Guangzhou 510300China Key Laboratory of Marine Environmental Survey Technology and Application Ministry of Natural ResourcesGuangzhou 510300China CNOOC Research Institute Co. Ltd.Beijing 100028China

Submarine groundwater discharge(SGD),which can be traced using naturally occurring Radium isotopes,has been recognized as a significant nutrient source and land-ocean interaction passage for the coastal waters of the Daya Bay,China.However,uncertainties in assessing SGD fluxes must still be discussed in detail.In this study,we attempted to utilize the Monte Carlo method to evaluate the uncertainties of radium-derived SGD flux in the northeast and entirety of the Daya Bay.The results show that the uncertainties of the SGD estimate in the northeast bay are very sensitive to variations in excess radium inventories as well as radium inputs from bottom sediments,while the uncertainties of the SGD estimate for the entire bay are strongly affected by fluctuations in radium inputs from bottom sediments and radium end-members of SGD.This study will help to distinguish the key factors controlling the accuracy of SGD estimates in similar coastal waters.

关键词： submarine groundwater discharge(SGD) Radium isotopes Monte-Carlo method Daya Bay uncertainty analysis

Optimization of enrichment and pretreatment of low-activity Radium isotopes in the open ocean

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海洋学报:英文版 2023年第8期42卷 171-177页

作者： Guiyuan Dai Guizhi Wang Qing Li Weizhen Jiang Fei Zhang State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies Xiamen UniversityXiamen 361102China College of Ocean and Earth Sciences Xiamen UniversityXiamen 361102China

In the open ocean,Radium isotopes are useful tracers of residence time and water-mass mixing.However,limited by the measurement resolution of commonly used gamma counters,the low activity of radium in the open ocean makes it necessary to enrich radium from large volumes of seawater and pretreat radium-enriched carriers prior to measurements.The commonly applied method of radium enrichment and pretreatment,however,has limitations of uneven coating of MnO_(2)on cartridges,relatively expensive cartridges,time-consuming issues during cartridge-ashing,ash loss during transfer,and changes of gamma counters efficiency caused by different ash weights.To address these issues,in this study we optimized the enrichment and pretreatment of low-activity radium prior to measurements.Firstly,we replaced commonly used acrylic cartridges with cheaper polypropylene cartridges,which took 6 h to be ashed,42 h shorter than for acrylic cartridges.Secondly,MnO_(2)-coated cartridges were prepared with a circulating hot acidic KMnO_(4)solution to ensure homogeneous coating.The radium extraction efficiency of this MnO_(2)-coated cartridge was 20%-61%higher than that prepared by directly immersing cartridges in the solution.The radium delayed coincidence counter efficiency for MnO_(2)-coated cartridge was stable with a moisture content of 0.05-1.Lastly,after ashing cartridges,instead of directly transferring the ash to a measurement vial,a mixture of hydroxylamine hydrochloride and hydrochloric acid was used to completely leach the ash for long-lived radium,followed by coprecipitation by BaSO_(4),to avoid potential loss of ash during transfer and variations in measurement geometry due to different ash weights.And the recovery of long-lived radium pretreatment was 94%-102%,which improved by 11%compared with the common method.In addition,the radium extraction efficiency of the MnO_(2)-coated cartridge varied from 3%to 4%within the in situ pump working flow rate of 4-7 L/min,which fell within the measurement errors.

关键词： Radium isotopes MnO_(2)-coated cartridge enrichment of Ra pretreatment of MnO_(2)-coated cartridges RaDeCC efficiency extraction efficiency

Using Radium isotopes to quantify submarine groundwater discharge at different scales in the Huanghe River Estuary,China

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海洋学报:英文版 2023年第8期42卷 32-39页

作者： Haowei Xu Disong Yang Xiaoyi Guo Maosheng Gao Guangquan Chen Diansheng Ji Shengtao Chen Huaming Yu Bochao Xu Frontiers Science Center for Deep Ocean Multispheres and Earth System/Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China Laboratory for Marine Ecology and Environmental Science Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China North China Sea Environmental Monitoring Center of State Oceanic Administration/Key Laboratory of Ecological Prewarning and Protection of Bohai Sea Ministry of Natural ResourcesQingdao 266033China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266033China Qingdao Institute of Marine Geology Qingdao 266071China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China Yantai Marine Center Ministry of Natural ResourcesYantai 264003China North China Sea Ecological Center Ministry of Natural ResourcesQingdao 266033China Key Laboratory of Ecological Prewarning and Protection of Bohai Sea Ministry of Natural ResourcesQingdao 266033China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China Sanya Oceanographic Institution Ocean University of ChinaSanya 572000China

As an important land-ocean interaction process,submarine groundwater discharge(SGD)is composed of multiple dynamical processes at different scales and plays an important role in the study of coastal ocean geochemical budgets.However,most of the existing studies focus on the quantification of the total groundwater discharge,few studies are about the differentiation and quantification of groundwater discharge processes at different scales(i.e.,short-scale SGD and long-scale SGD).As a world-class river,the Huanghe River is highly turbid and heavily regulated by humans.These natural and anthropogenic factors have a significant impact on groundwater discharge processes in the Huanghe River Estuary(HRE).In this study,the distribution patterns of the natural geochemical tracer Radium isotopes(^(224)Ra and^(223)Ra)and other hydrological parameters in the HRE were investigated during four cruises.By solving the mass balance of^(224)Ra and^(223)Ra in the HRE,the long-scale SGD flux was quantified as 0.01−0.19 m/d,and the short-scale SGD flux was 0.03−0.04 m/d.The rate of short-scale SGD remained essentially constant among seasons,while the rate of long-scale SGD varied considerably at different periods and showed a synchronous trend with the variation of river discharge.The results of this study are significant for understanding the SGD dynamics in the HRE and the contribution of SGD to the ocean geochemical budgets.

关键词： Radium isotopes submarine groundwater discharge Huanghe River Estuary

Submarine groundwater discharge and associated nutrient fluxes in the Greater Bay Area, China revealed by radium and stable isotopes

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Geoscience Frontiers 2021年第5期12卷 397-410页

作者： Qianqian Wang Xuejing Wang Kai Xiao Yan Zhang Manhua Luo Chunmiao Zheng Hailong Li State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control School of Environmental Science and EngineeringSouthern University of Science and TechnologyShenzhenGuangdong 518055China School of Environmental Science and Engineering Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution ControlSouthern University of Science and TechnologyShenzhenGuangdong 518055China MOE Key Laboratory of Groundwater Circulation&Environment Evolution and School of Water Resources and Environment China University of Geosciences(Beijing)Beijing 100083China

The estuary-bay system is a common and complex coastal environment.However,quantifying submarine groundwater discharge(SGD)and associated nutrient fluxes in the complex coastal environment is challenging due to more dynamic and complicated riverine discharge,ocean processes and human activities.In this study,SGD and SFGD(submarine fresh groundwater discharge)fluxes were evaluated by combining stable and Radium isotopes in the Guangdong-Hong Kong-Macao Greater Bay Area(GBA),a typical estuary-bay system.We first built a spatially distributed radium mass balance model to quantify SGD fluxes in coastal areas of GBA integrating the Pearl River Estuary(PRE),bays and shelf.We then used the stable water isotope(d2 H and d18O)end-member mixing model to distinguish submarine fresh groundwater discharge(SFGD)from SGD.Based on the 228Ra mass balance,the estimated SGD fluxes in the PRE,adjacent bay,and shelf areas were(6.14±2.74)×10^(8) m^(3) d^(-1),(3.00±1.11)×10^(7) m^(3) d^(-1),and(5.00±5.64)×10^(8) m^(3) d^(-1),respectively.Results showed that the largest area-averaged SGD was in the PRE,followed by that in the adjacent shelf and the bay.These differences may be mainly influenced by ocean forces,urbanization and benthic topographies controlling the variability of groundwater pathways.Further,the three end-member mixing model of ^(228)Ra and salinity was developed to confirm the validity of the estimated SGD using the Ra mass balance model.In the two models,groundwater endmember and water apparent age estimation were the main sources of uncertainty in SGD.The estimated SFGD flux was(1.39±0.76)108 m^(3) d^(-1),which accounted for approximately 12%of the total SGD.Combining stable and Radium isotopes was a useful method to estimate groundwater discharge.Moreover,the estimated SGD associated dissolved inorganic nitrogen(DIN)flux was one order of magnitude higher than other DIN sources.SGD was considered to be a significant contributor to the DIN loading to the GBA.The findings of this study are expected to provide valuable i

关键词： Radium isotopes Stable isotopes Submarine fresh groundwater discharge Nutrients Coastal aquifers Pearl River estuary

Evaluation of shallow groundwater discharge fluxes and nutrient fluxes in the west of Qinghai Lake using Radium isotopes

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Acta Geologica Sinica(English Edition) 2014年第S1期88卷 145-148页

作者： KONG Fancui SHA Zhanjiang SU Weigang YU Chenguang Qinghai Institute of Salt Lakes Academy of Science University of the Chinese Academy of Sciences

We collected 14 samples and 9 samples for surface water in Quan bay and the north bay of Qinglai Lake respectively,as well as 11 samples for groundwater and 3 samples for river water.First the water samples were filte... 详细信息

关键词： Qinghai Lake Radium isotopes shallow groundwater SGD

radium-traced nutrient outwelling from the Subei Shoal to the Yellow Sea:Fluxes and environmental implication

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Acta Oceanologica Sinica 2022年第6期41卷 12-21页

作者： Jian’an Liu Dongyan Liu Jinzhou Du State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China

The Subei Shoal is the largest sandy ridge in the southern Yellow Sea and is important source for nutrient loading to the sea.Here,the nutrient fluxes in the Subei Shoal associated with eddy diffusion and submarine groundwater discharge(SGD)were assessed to understand their impacts on the nutrient budget in the Yellow Sea.Based on the analysis of 223 Ra and 224 Ra in the field observation,the offshore eddy diffusivity mixing coefficient and SGD were estimated to be 2.3×10^(8)cm^(2)/s and 2.6×10^(9)m^(3)/d(16 cm/d),respectively,in the Subei Shoal.Combined the significant offshore decreasing gradients of nutrient in seawater of the Subei Shoal,the spatially integrated nutrient outwelling fluxes to the Yellow Sea were 262-1465μmol/(m^(2)·d)for DIN,5.2-21μmol/(m^(2)·d)for DIP and711-913μmol/(m^(2)·d)for DSi.Compared to the riverine input,atmospheric deposition and mariculture,nutrient outwelling from the Subei Shoal might play an important role in nutrient budget of the Yellow Sea.These nutrient fluxes could provide 4.1%-23%N and 1.3%-5.3%P requirements for the primary productivity,and the deviated DIN/DIP ratios have the potential to affect the growth of phytoplankton in the marine ecosystem of the Yellow Sea.

关键词： nutrient outwelling eddy diffusion submarine groundwater discharge Radium isotopes Subei Shoal Yellow Sea

Advances in the study of submarine groundwater discharge(SGD)in China

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Science China Earth Sciences 2022年第10期65卷 1948-1960页

作者： Yan ZHANG Xuejing WANG Yan XUE Changpei ZOU Manhua LUO Gang LI Lei LI Laitong CUI Hailong LI School of Water Resources and Environment China University of Geosciences-BeijingBeijing 100083China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

Submarine groundwater discharge(SGD)is a critical land-ocean process in coastal areas and an essential component of the global hydrological cycle.Thus,hydrologists and oceanographers are paying more attention to SGD.SGD transports large amounts of materials into the ocean,including nutrients,carbon,and metals,and thus plays a vital role in the cycling of marine materials and affects the ecological environments of nearshore areas.This study examined the research status of SGD and its environmental effects in China,including a systematic analysis of radium activities and nutrient contents in groundwater,SGD rates,and the contribution of SGD to nutrients in various coastal ecosystems(bays,estuaries,continental shelves,and lagoons).The results showed the median concentrations of groundwater nutrients(dissolved inorganic nitrogen DIN,dissolved inorganic phosphorus DIP,and dissolved inorganic silicon DSi),SGD rates,and SGD-derived DIN and DIP in estuarine areas far exceeded those in the other three ecosystems studied.This result could be attributed to the complex hydrodynamic conditions of estuary areas as well as the considerable influence of human activities.Conversely,the lowest SGD rates and three inorganic nutrient species via SGD were observed in large scale continental shelves.SGD-derived nutrient fluxes were comparable to riverine inputs along the entire coast of China,which significantly affected the nutrient budget,nutrient composition,and primary productivity of coastal waters.Finally,this review suggests further research of SGD in three aspects:(1)accurate assessment,(2)its environmental effects,and(3)its regulatory strategies.

关键词： Submarine groundwater discharge(SGD) Radium isotopes Nutrients Ecosystems Environmental effects

Radium isotopes in an Oil-Field Produced Lake near Baku, Azerbaijan

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Journal of Environmental Protection 2016年第9期7卷 1149-1156页

作者： Famil Yusif Humbatov Bahruz Allahverdi Suleymanov Majid Mirza Ahmedov Majid Mirza Ahmedov Valeh Saleh Balayev Institute of Radiation Problems National Academy of Sciences of Azerbaijan Baku Azerbaijan

An assessment of radiologically enhanced residual materials generated during oil and gas production in near Baku, Azerbaijan, was conducted. Distribution of the 228Ra/226Ra Activity Ratio (AR) with depth in a sediment core from radium lake was examined. The dashed line represented ingrowth assuming that 228Ra was below equilibrium with 232Th in the young sediments near the top and reached equilibrium at a depth around 10 cm. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant and age of oil field lake. The results indicate that, the upper two layers in the core (up to 4 cm) contain fallout 137Cs so at least these layers are no older than about 40 yrs. Formation waters that are sent to disposal ponds may consist of accumulated heavy hydrocarbons, paraffin, inorganic solids, and heavy emulsions. We report here results of chemical and radiochemical measurements from formation waters separated from oil pumped from approximately 700 m below ground near Baku, Azerbaijan. Our results also include data from a formation water storage pond (“radium lake”) where the waters are temporarily stored after oil is separated and then eventually disposed of by pumping into the Caspian Sea. We also analyzed the associated sediment for radiochemical components. Our study was intended to investigate how radium fractionated between the pond water and sediments.

关键词： Oil Industry Formation Water Sediments Radium isotopes NORM Azerbaijan

Submarine groundwater discharge and benthic biogeochemical zonation in the Huanghe River Estuary

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Acta Oceanologica Sinica 2022年第1期41卷 11-20页

作者： Guangquan Chen Bochao Xu Shibin Zhao Disong Yang William C.Burnett Shaobo Diao Maosheng Gao Xingyong Xu Lisha Wang Key Laboratory of Coastal Science and Integrated Management First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Frontiers Science Center for Deep Ocean Multispheres and Earth System/Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China Marine Ecology and Environmental Science Laboratory Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee 32306USA Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China

Submarine groundwater discharge(SGD)has received increasing attention by studies on coastal areas;however,its effects on biogeochemical zonation have not been investigated to date.The Huanghe River Estuary(HRE)is a world class river estuary with high turbidity,and heavy human regulation.This study investigated how SGD is related to the benthic biogeochemistry of the HRE.Based on the distribution of several parameters(e.g.,salinity,temperature,dissolved oxygen(DO)levels,p H,Radium isotopes,and nutrients),the HRE was subdivided into six different zones,and the SGD fluxes within each zone were quantified and compared.The highest SGD flux was found in the northwest nearshore zone,where it was more than one order of magnitude higher than in the offshore zone.High SGD resulted in low DO and p H,but high nutrient levels in the benthic boundary layer.The southeast nearshore zone was also characterized by high SGD flux,but benthic waters were more oxic because of the dominating inputs by the Huanghe River.These data suggest that such a zonation would help to understand benthic biogeochemical processes.High SGD may not only contribute to the estuarine nutrient budget,but may also contribute to the formation of hypoxia and acidification.

关键词： SGD zonation benthic biogeochemistry Radium isotopes Huanghe River Estuary

Analysis of Radium isotopes in Surface Waters nearby a Phosphate Mining with NORM at Santa Quiteria,Brazil

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Journal of Environmental Protection 2014年第3期5卷 193-199页

作者： Wagner de S.Pereira Alphonse Kelecom Juliana R.de S.Pereira Multidisciplinary Group of Radioprotection(GMR) Servico de RadioprotecaoUnidade de Tratamento de MinerioIndustrias Nucleares do BrasilCaldasBrazil Laboratory of Radiobiology and Radiometry Pedro Lopes dos Santos(LARARA-PLS) Group of Environmental Themes Assessment(GETA)Universidade Federal Fluminense(UFF)NiteroiBrazil Interdisciplinary Under-Graduation in Science and Technology Universidade Federal de AlfenasPocos de CaldasBrazil

The Radium isotopes 226Ra and 228Ra were analyzed in surface water at six points in the neighborhood of a mine of phosphate, associated with uranium, in the region of Santa Quitéria, state of Ceará, Brazil. Water samples were collected during twenty months, filtered and the concentrations of activity determined in the soluble and particulate phases. The results were analyzed using the Principal Component Analysis (PCA) for ordination of environmental data, and also by ANOVA, Tukey and Z tests to compare sets of data considering the radionuclides, the two analyzed phases and the six collecting points. The PCA identified four groups that included all collecting points, using aggregation features such as radionuclide and analyzed phase. The first group is composed by the samples of 226Ra in the soluble phase;the second group by samples of 226Ra in the particulate phase;the third one by 228Ra in the soluble phase, and finally, the fourth group by 228Ra in the particulate phase. This last group has two discrepant points (01 and 06). Statistical analysis identified differences between the concentrations of activity of radionuclides (228Ra higher than 226Ra) and in analyzed phases (soluble phase higher than the particulate one) but showed no differences between sampled points.

关键词： Radioecology Environmental Radioprotection NORM Mining Radium isotopes PCA