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Relations between mercury fractions and microbial community components in seawater under the presence and absence of probable phosphorus limitation conditions

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Journal of Environmental Sciences 2019年第1期31卷 145-162页

作者： Igor ?ivkovi? Vesna Fajon Jo?e Kotnik Yaroslav Shlyapnikov Kristina Obu Vazner Ermira Begu Stefanija ?estanovi? Danijela ?anti? Ana Vrdoljak Slaven Jozi? Mladen ?oli? Jelena Lu?i? Jere Ve?a Grozdan Ku?pili? Marin Ordulj Frano Mati? Branka Grbec Natalia Bojani? ?ivana Nin?evi? Gladan Milena Horvat Department of Environmental Sciences Jo?ef Stefan Institute Jo?ef Stefan International Postgraduate School Ecological Engineering Institute Maribor 2000 Slovenia laboratory of Marine Microbiology Institute of Oceanography and FisheriesSplit 21000 Croatia Laboratory of Chemical Oceanography and Sedimentology of the Sea Institute of Oceanography and FisheriesSplit 21000 Croatia Laboratory of Chemical Oceanography and Sedimentology of the Sea Institute of Oceanography and Fisheries Department of Marine Studies University of SplitSplit 21000 Croatia laboratory of Physical oceanography Institute of Oceanography and FisheriesSplit 21000 Croatia laboratory of Plankton and Shellfish Toxicity Institute of Oceanography and FisheriesSplit 21000 Croatia

Microbial transformations of toxic monomethylmercury(MMHg) and dissolved gaseous mercury(DGM) at the lower levels of the marine food web are not well understood, especially in oligotrophic and phosphorus-limited seas. To examine the effects of probable phosphorus limitation(~PP-limitation) on relations between mercury(Hg) fractions and microorganisms, we determined the total mercury(THg), total methylated mercury(MeHg), DGM, and microbiological and chemical parameters in the Central Adriatic sea. Using statistical analysis, we assessed the potential microbial effects on Hg transformations and bioaccumulation. Only in the absence of ~PP-limitation conditions(^(NO–P)P-limitation) is MeHg significantly related to most chemical and microbial parameters, indicating metabolism-dependent Hg transformations.The heterotrophic activity of low nucleic acid bacteria(abundant in oligotrophic regions)seems responsible for most of Hg methylation under ^(NO–P)P-limitation. Under these conditions,DGM is strongly related to microbial fractions and chlorophyll a, indicating biological DGM production, which is probably not metabolically induced, as most of these relations are also observed underPP-limitation. MMHg biomagnification was observed through an increased bioaccumulation factor from microseston to mesozooplankton. Our results indicate that Hgtransformations and uptake might be enhanced under ^(NO–P)P-limitation conditions, emphasizing their impact on the transfer of Hg to higher trophic levels.

关键词： Mercury speciation Methylmercury Probable phosphorus limitation Microbial community

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Distribution and chemical speciation of dissolved inorganic arsenic in the Yellow sea and East China sea

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Acta Oceanologica Sinica 2015年第6期34卷 12-20页

作者： WU Bin SONG Jinming LI Xuegang Key laboratory of Marine Ecology and Environmental Sciences Institute of Oceanology Chinese Academy of Sciences Key laboratory of Marine sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration

Distribution and chemical speciation of dissolved inorganic arsenic were examined in Yellow sea and East China sea. Results demonstrated that：（1） both As（Ⅲ） and As（Ⅴ） were detected, with As（V） dominated at 40% stations of surface water and 51% stations of bottom water; （2） influenced by the exchange of fresh and sea water, the type of surface sediment and the transport of various water masses, large values in surface water were observed along the coastal region and in the same latitude of Changjiang River Estuary and Hangzhou Bay, and in bottom water found in the southern area where the Taiwan Warm Current and Kuroshio Current influenced; （3） As（Ⅲ） behaved non-conservatively in Changjiang River Estuary. Man-derived inputs cause substantial positive deviation from the theoretical dilution. The negative correlation of As（Ⅴ） to salinity in surface water suggested that it behaved conservatively during the transportation along Changjiang River Estuary. While, the occurrence of As（Ⅴ） up to the linear fit in bottom water indicated the eventual transfer from dissolved phase to particulate phase, which was impossible to be determined without the knowledge of arsenic level and speciation in suspended particulate matter. Further study is needed on the arsenic source/sink relationships based on the distribution profiles.

关键词： dissolved inorganic arsenic distribution speciation Yellow sea East China sea

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Major and trace element geochemistry of the mid-Bay of Bengal surface sediments: implications for provenance

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Acta Oceanologica Sinica 2017年第3期36卷 82-90页

作者： LI Jingrui LIU Shengfa FENG Xiuli SUN Xingquan SHI Xuefa College of Marine Geosciences Ocean University of China Key laboratory of Marine sedimentology and Environmental Geology The First Institute of OceanographyState Oceanic Administration laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology

The major and trace elements in 110 surface sediment samples collected from the middle of the Bay of Bengal（mid-Bay of Bengal） are analyzed to investigate provenance. Si levels are highest, followed by Al, and the distributions of these two elements are identical. The average CIA＊（chemical index of alteration） value is 72.07,indicating that the degree of weathering of the sediments in the study area is intermediate between those of sediments of the Himalayan and Indian rivers. Factor analyses and discrimination function analyses imply that the two main provenances are the Himalayan and the Indian continent. The inverse model calculation of the Tinormalized element ratios of the Bay of Bengal sediments indicate an estimated average contribution of 83.5%and 16.5% from the Himalayan and peninsular Indian rivers to the study area, respectively. The Himalayan source contributes more sediment to the eastern part of the study area, whereas the western part receives more sediment from the Indian Peninsula than did the eastern part. The primary mechanisms for deposition of sediments in the study area are the transport of Himalayan matter by turbidity currents and river-diluted water and the transport of Indian matter to the study area by a surface circulation in the Bay of Bengal, particularly the East India Coastal Current.

关键词： major and trace element Bay of Bengal provenance quantification factor analyses

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Assessment of structural stability in Bohai sea area based on AHP-GDM model

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Acta Oceanologica Sinica 2013年第4期32卷 41-48页

作者： XIU Zongxiang LIU Baohua XIE Qiuhong LI Xishuang LIU Chenguang PEI Yanliang ZHENG Yanpeng The First Institute of oceanography State Oceanic Administration Key laboratory of Marine sedimentology and Environmental Geology National Deep sea Center

The AHP-GDM model is used for the assessment of structural stability, with the Bohai sea area as an exam- ple. In this model, the credit degree of each expert is calculated through the assessment matrix based on the similarity and diversity of vector. The comprehensive opinions of expert panel are quantitatively obtained by considering the effect ofcredit degree. According to the geological structural setting, the Bohai sea is di- vided into twelve assessment zones of structural stability by non-uniform element method. The structural stability grade of each zone is obtained on the basis of the latest geophysical data, earthquake statistical data, and the information of fault activities, current stress field and crustal deformation. The results show that there are one relatively stable area, three relatively sub-stable areas, six relatively sub-unstable areas and two relatively unstable areas. The assessment results of non-uniform element method are very close with those of uniform grid method with size of 0.25 in longitude direction and 0.14 in latitude direction. However the workload of non-uniform element method is only 1 / 16 of the latter. Compared with traditional assessment methods of structural stability, a more objective and reliable assessment result can be obtained by combining non-uniform element method and AHP-GDM model.

关键词： AHP-GDM Mode Bohai sea structural stability non-uniform element method

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Environmental record from the mud area on the inner continental shelf of the East China sea since the mid-Holocene

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Acta Oceanologica Sinica 2011年第4期30卷 43-52页

作者： LIU Shengfa SHI Xuefa LIU Yanguang WU Yonghua YANG Gang First Institute of oceanography State Oceanic Administration Qingdao 266061 China Key laboratory of Marine sedimentology and Environmental Geology State OceanicAdministration Qingdao 266061 China

Paleoclimate record was revealed in Core MZ01 covering the mid-Holocene in age,located in the mud area of the inner continental shelf of the East China sea. The ancient environment featured low-energy shallow sea shelf deposition formed mainly by coastal currents. The results show that temporal variation in geochemistry corresponds with the climate changes inferred from historical record. Relatively low MgO/Al 2 O 3,CaO/K 2 O and high Al 2 O 3 /Na 2 O,K 2 O/Na 2 O,MnO/CaO values reflected a warm and humid climate in general,and vice versa. Therefore,these chemical indices could be applied to identify the variation of palaeoclimate in eastern China. The authors reconstructed the history of mid-Holocene climatic variation of the inner continental shelf of the East China sea. From 8 300 a BP to 4 200 a BP,the climate was moderately warm and humid. From 4 200 a BP to 2 000 a BP,the climate turned cool and dry,and the regional climate frequently fluctuated in alternation of cool-dry periods（3 700 a BP,2 850 a BP and 2 400 a BP） and warm-wet periods（3 250 a BP and 2 650 a BP） . After 2 000 a BP,the climate of the study area gradually turned warm again,while the Little Ice Age,a cold event centered at around 250 a BP was indicated by those geochemical indices as mentioned above.

关键词： Holocene East China sea mud area major element palaeoclimate East Asia monsoon

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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

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Geochemistry of mafic rocks and melt inclusions and their implications for the heat source of the 14.0°S hydrothermal field, South Mid-Atlantic Ridge

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Chinese Journal Of Geochemistry 2014年第4期33卷 325-335页

作者： LI Bing SHI Xuefa YANG Yaomin YE Jun GAO Jingjing ZHENG Wenqin Key laboratory of Marine sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration National Deep sea Center State Oceanic Administration Institute of Geochemistry Chinese Academy of Sciences

Fresh rocks sampled from the 14.0°S hydrothermal field of the South Atlantic Ridge can be divided into two categories: olivine-gabbro and basalt. The olivine-gabbro is composed mainly of three types of minerals: olivine, clinopyroxene and plagioclase, while a multitude of melt inclusions occur in the plagioclase phenocrysts of the basalts. We analyzed the whole-rock, major and trace elements contents of the basalts, the mineral chemistry of phenocrysts and melt inclusions in the basalts, and the mineral chemistry of olivine-clinopyroxene-plagioclase in the olivine-gabbro, then simulated magma evolution within the crust using the COMAGMAT program. The whole-rock geochemistry shows that all the basalts exhibit typical N-MORB characteristics. In addition, the mineral chemistry characteristics of the olivine-gabbro(low-Fo olivine, low-Mg# clinopyroxene, high-Ti O2 clinopyroxene, low-An plagioclase), show that strong magma differentiation occurred within the crust. Nevertheless, significant discrepancies between those minerals and phenocrysts in the basalts(high-Fo olivine, high-An plagioclase) reflect the heterogeneity of magma differentiation. High Mg#(≈0.72) melt inclusions isobaric partial crystallization simulations suggest that the magma differentiation occurred at the depth shallower than 13.03 km below the seafloor, and both the vertical differentiation column shows distinct discrepancies from that of a steady-state magma chamber. Instead, a series of independent magma intrusions probably occurred within the crust, and their corresponding crystallized bodies, as the primary high-temperature thermal anomalies within the off-axis crust, probably act as the heat source for the development of the 14.0°S hydrothermal system.

关键词：熔融包裹体大西洋中脊地球化学热液区热源基性岩矿物化学岩浆演化

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The distribution and variation of elements in sediments off the Huanghe (Yellow) River mouth

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Chinese Journal of Oceanology and Limnology 2013年第4期31卷 876-885页

作者：乔淑卿石学法高晶晶刘焱光杨刚朱爱美王昆山 Key laboratory of Marine sedimentology & Environmental Geology First Institute of OceanographyState Oceanic Administration

Surface sediment samples collected off the Huanghe (Yellow) River mouth during the period 2007-2009 were analyzed for major and trace element concentrations. Concentrations of 16 elements were measured using X-ray fluorescence spectrometry. Results demonstrate that sediment grain size is the dominant factor controlling the spatial variations of elemental concentrations. Correlation and cluster analyses allowed classification of the study area into four geochemical regions: Regions I and III are characterized by high concentrations of Al2O3 , Fe2O3 , MgO, Na2O, K2O,Cr,Cu,Mn,Ni,Pb,V, and Zn, and contain fine-grained sediments with mean grain size (Mz )sea from the Huanghe River and its tributaries is enriched in Ca. Thus, the Ca/Al ratio was used as an indicator of the proportion of sediments in the study area that originated from the Huanghe River. Ca/Al ratios decrease from Regions Ⅰ and Ⅱ (located in the nearshore zone of the Huanghe River delta) to Regions III and IV (distributed in the offshore zone of the northern Huanghe River delta, southern and southeastern Laizhou Bay area).

关键词：黄河三角洲地区河口沉积物微量元素黄色关闭 X射线荧光光谱法元素浓度研究区域

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Discharge electrode configuration effects on the performance of a plasma sparker

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Plasma Science and Technology 2017年第9期19卷 48-55页

作者：裴彦良张连成黄逸凡严辉朱鑫磊刘振闫克平 Key laboratory of Marine sedimentology and Environmental Geology First Institute of OceanographySOA laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology Institute of Industrial Ecology and Environment College of Chemical and Biological EngineeringZhejiang University

A multi-electrode array is commonly applied in a plasma sparker to generate stable acoustic pulses.In this paper, the effects of the electrode configuration on the performance of a plasma sparker have been investigated. In terms of the load electrical characteristics, the electrode radius and distance have negligible influence on the electric characteristics, whereas a larger electrode number results in a smaller voltage and a larger current but has little effect on the load energy. Regarding the acoustic characteristics, both the expansion and collapse pulses can be increased by decreasing the electrode tip radius. the influence of the electrode number and electrode gap distance on the amplitude of the expansion pulse was found to be negligible. And the amplitude of the collapse pulse decreases significantly with increasing electrode number. Increasing the electrode number decreases the energy efficiency for intense bubble interactions, thus, a small electrode tip radius and a small electrode number are preferred for the design of a plasma sparker if the total discharge energy is given.

关键词： negligible collapse bubble radius decreasing preferred neglected initially Figure intense

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Study on Sound-Speed Dispersion in A Sandy Sediment at Frequency Ranges of 0.5–3 kHz and 90–170 kHz

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China Ocean Engineering 2017年第1期31卷 103-113页

作者： YU Sheng-qi LIU Bao-hua YU Kai-ben KAN Guang-ming YANG Zhi-guo National Deep sea Center State Oceanic Administration Qingdao 266237 China Key laboratory of Marine sedimentology and Environmental Geology First Institute of Oceanography Qingdao 266061 China laboratory for Marine Geology Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China

In order to study the properties of sound-speed dispersion in a sandy sediment, the sound speed was measured both at high frequency （90-170 kHz） and low frequency （0.5-3 kHz） in laboratory environments. At high frequency, a sampling measurement was conducted with boiled and uncooked sand samples collected from the bottom of a large water tank. The sound speed was directly obtained through transmission measurement using single source and single hydrophone. At low frequency, an in situ measurement was conducted in the water tank, where the sandy sediment had been homogeneously paved at the bottom for a long time. The sound speed was indirectly inverted according to the traveling time of signals received by three buried hydrophones in the sandy sediment and the geometry in experiment. The results show that the mean sound speed is approximate 1710-1713 m/s with a weak positive gradient in the sand sample after being boiled （as a method to eliminate bubbles as much as possible） at high frequency, which agrees well with the predictions of Biot theory, the effective density fluid model （EDFM） and Buckingham＇s theory. However, the sound speed in the uncooked sandy sediment obviously decreases （about 80%） both at high frequency and low frequency due to plenty of bubbles in existence. And the sound-speed dispersion performs a weak negative gradient at high frequency. Finally, a water-unsaturated Biot model is presented for trying to explain the decrease of sound speed in the sandy sediment with plenty of bubbles.

关键词： acoustic properties of sediment sound-speed dispersion sandy sediment bubbles

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