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On the integrity of a commercial cassette ultrafiltration membrane: implications for marine colloidal biogeochemistry

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Acta Oceanologica Sinica 2014年第9期33卷 109-116页

作者： LIN Liangshi CAI Yihua sun xiuwu CHEN Min State Key Laboratory of Marine Environmental Science and College of Ocean and Earth Science Xiamen University Third Institute of Oceanography State Oceanic Administration

The performance and integrity of a cassette cross-flow ultrafilter （Pellicon 2, Millipore） are examined with a suite of macromolecules of different molecular masses. The retention coefficient during the cross-flow ultrafiltration experiments increases with increasing molecular mass and reaches 90% with 10 kDa dextran in both milli-Q water and ultrafiltered seawater media. Based on a 90% retention coefficient, the molecular mass cut-off for the ultrafiltration membrane is defined at 10 kDa, which is ten times （1 kDa） that rated by the manufacturer. To further validate the accuracy of the laboratory calibration, the samples from the lower Zhujiang River and the Jiulong River Estuary are ultrafiltered with the cassette ultrafiltration membrane and the colloidal organic carbon abundances in these samples are quantified with the ultrafiltration per- meation model based on time series permeation subsamples. The colloidal organic carbon abundances are 5.8%-21.1% in the Jiulong River Estuary and 5.6%-11.0% in the lower Zhujiang River. These are consistent with the reported values for both estuaries as well as with the colloidal organic carbon abundances in ma- rine environments over the coastal and open oceans with 10 kDa cut-off membranes. Therefore, these field data support the laboratory calibration result and indicate the validity of the experimental and quantification procedure adopted. The discrepancy between the nominal molecular mass cut-off and the actual pore size of the ultrafiltration membrane should be of great concern for research in colloidal and nanoparticle biogeochemistry. Careflfl examination of the membrane integrity should be taken during ultrafiltration ex- oeriments in order to avoid misleading molecular mass cut-off information.

关键词： cross-flow ultrafiltration membrane calibration colloidal organic carbon Iiulong RiverEstuary Zhujiang River Estuary

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Speciation, distribution, and potential ecological risk assessment of heavy metals in Xiamen Bay surface sediment

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Acta Oceanologica Sinica 2014年第4期33卷 13-21页

作者： LIN Cai LIU Yang LI Wenquan sun xiuwu JI Weidong College of Ocean and Earth Science Xiamen University Third Institute of Oceanography State Oceanic Administration

Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals （Cu, Pb, Zn, Cd, and Cr） in this area were studied us-ing the sequential extraction method and ecological risk assessment method. The results indicated：（1） the total concentrations of these heavy metals were influenced by runoff, industrial wastewater, and sewage, and were all higher in the coastal area than the offshore area while the highest area of Pb was a little far-ther away from the coastal water due to atmosphere deposition;（2） sequential extractions suggested that Cu was mainly composed with residual and Fe/Mn-oxide bound fractions, Pb was bound to Fe/Mn-oxide, Zn and Cr were dominated by residual, and Cd bound to exchangeable and carbonate fractions; （3） the order of migration and transformation sequence was Cd＆gt;Pb＆gt;Cu＆gt;Zn＆gt;Cr and the degree of pollution was Cd＆gt;Pb＆gt;Cu＆gt;Zn＆gt;Cr;and （4） the ratios of the secondary and primary phases showed that Zn and Cr were both clean, Cu may be polluted, Pb was moderately polluted, while Cd was heavily polluted.

关键词： Xiamen Bay heavy metals speciation distribution ecological risk

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Distribution of dissolved oxygen and causes of maximum concentration in the Bering Sea in July 2010

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Acta Oceanologica Sinica 2014年第6期33卷 20-27页

作者： sun xiuwu LIN Cai CHEN Yong ZHANG Yuanbiao WANG Jigang JI Weidong Third Institute of Oceanography State Oceanic Administration College of Ocean and Earth Sciences Xiamen University

According to data obtained in the Bering Sea during the 4th Chinese National Arctic Research Expedition, the distribution of dissolved oxygen （DO） was studied, causes of its maximum concentration were discussed, and the relationships between DO and other parameters, such as saliniW, temperature, and chlorophyll a were analyzed. The results showed DO concentration ranged from 0.53 to 12.05 mg/L in the Bering Sea basin. The upper waters contained high concentrations and the maximum occurred at the depth range from 20 to 50 m. The DO concentration decreased rapidly when the depth was deeper than 200 m and reached the minimum at the depth range from 500 to 1000 m, and then increased slowly with the depth increasing but still kept at a low level. On the shelf, the DO concentration ranged from 6.53 to 16.63 mg/L with a mean value of 10.75 mg/L, and showed a characteristic of decreasing from north to south. The DO concentration was higher in the area between the Bering Sea and Lawrence Island and was lower in the southeast and southwest of Lawrence Island at the latitude of 62°N. The formation of maximum DO concentration was concerned with phytoplankton photosynthesis and formation of the themocline. To the south of Sta. B07 in the Bering Sea basin, the oxygen produced by photosynthesis permeated to the deeper water and the themocline made it difficult to exchange vertically, and to the north of Sta. B07, the maximum DO concen- tration occurred above the themocline due to phytoplankton activities. On the shelf, the oxygen produced by phytoplankton photosynthesis gathered at the bottom of the thermocline and formed the DO maximum concentration. In the Bering Sea basin, the DO and salinity showed a weak negative correlation （r=0.40） when the salinity was lower than 33.1, a significant negative correlation （r=-0.92） when the salinity ranged from 33.1 to 33.7, and an irregular reversed parabola （r=0.95） when the salinity was greater than 33.7. Key words： Bering Sea, dissolved

关键词： Bering Sea dissolved oxygen maximum concentration stratification chlorophyll a

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Bioturbation coefficients and organic carbon degradation rates of deep-sea sediments in the central-eastern tropical Pacific

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Acta Oceanologica Sinica 2024年第10期43卷 100-106页

作者： Feng Lin Cai Lin xiuwu sun Hui Lin Li Lin Fangfang Deng Kaiwen Tan Peng Lin Laboratory of Marine Ecological Environmental Early Warning and Monitoring Third Institute of OceanographyXiamen 361005China Savannah River Ecology Laboratory University of GeorgiaAiken 29802USA

The biogeochemical processes of marine sediments are influenced by bioturbation and organic carbon decomposition,which is crucial for understanding global element cycles and climate *** sediment cores were acquired in 2017 from abyssal basins in the central-eastern tropical Pacific to determine the bioturbation and organic carbon degradation *** radioactivity concentrations of 210Pb and 226Ra in the sediment cores were measured,indicating the presence of significant excess 210Pb(210Pbex)signals in the sediment ***,a manganese nodule was discovered in one core,which had a substantial influence on the distribution of *** the exception of this anomalous finding,the bioturbation coefficients in the remaining core were estimated to be 10.6 cm^(2)/a using a steady-state diffusion model,greater than most of the deep-sea sediments from the equatorial eastern *** using a bio-diffusion model,we further calculated the degradation rates of organic carbon(8.02 ka-1),which is also higher than other areas of the *** findings displayed the presence of a biologically active benthic ecosystem in the central-eastern tropical Pacific.

关键词： 210Pb 226Ra bioturbation tropical Pacific organic carbon degradation rate

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Temporal and spatial distribution characteristics of nutrients in Clarion-Clipperton Fracture Zone in the Pacific in 2017

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Acta Oceanologica Sinica 2022年第1期41卷 1-10页

作者： Baohong Chen Kaiwen Zhou Kang Wang Jigang Wang Sumin Wang xiuwu sun Jinmin Chen Cai Lin Hui Lin Third Institute of Oceanography Ministry of Natural ResourceXiamen 361005China Institute for Advanced Ocean Study Ocean University of ChinaQingdao 266003China

This research investigated eight stations in Clarion-Clipperton Fracture Zone(CCFZ)in the eastern tropical Pacific in 2017 to study the spatial distribution characteristics of nutrients and chlorophyll a(Chi a)concentration,and compared nutrient concentrations and molar ratios with those of other investigations 20 years ago in the same *** study found that dissolved inorganic nutrient(N,P and Si)concentrations were lowest in the upper layer,and increased from surface to some depths,then they decreased a little to the bottom.N was the limited nutrient factor for the growth of phytoplankton *** nutrient concentrations and molar ratios have no obvious changes in 2017 comparing those in 1998-2003,supplemented from the equatorial Pacific,nutrient concentrations in the study area were higher than those in seamounts in the North Pacific and Station ***,this study used Generalized Additive Models(GAMs)to infer the underlying bottom-up factors controlling phytoplankton abundance(Chi a concentration),showing that depth,salinity and PO^-P concentration were major factors controlling the growth of phytoplankton ***,this study can provide basic data and theoretical support for the development of polymetallic nodule area and its long-term impact assessment on the environment.

关键词： nutrients Chla GAMs CCFZ Pacific

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The particle fluxes in sediment traps from Niulang Guyot area in the Northwest Pacific Ocean

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Acta Oceanologica Sinica 2022年第11期41卷 34-44页

作者： xiuwu sun Jinmin Chen Baohong Chen Cai Lin Yang Liu Jiang Huang Zhong Pan Kaiwen Zhou Qing He Fangfang Kuang Hui Lin Laboratory of Marine Ecological and Environment Early Warning and Monitoring Third Institute of OceanographyMinistryof Natural ResourcesXiamen 361005China Ocean Dynamics Laboratory Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China

The flux of settling particles in the ocean has been widely explored since 1980s due to its important role in biogenic elements cycling,especially in the transport of particulate organic carbon(POC)in the deep ***,research in the seamount area of the oligotrophic subtropical Northwest Pacific Ocean is *** this work,two sediment traps were deployed at the foot and another two at the hillside of Niulang Guyot from August2017 to July *** magnitude and composition of particle fluxes were *** main factors influencing the spatial variations of the fluxes were *** results indicated a low particulate flux from Niulang Guyot area in the Northwest Pacific Ocean,reflecting low primary productivity of the oligotrophic *** total mass flux(TMF)decreased from 2.57 g/(m^(2)·a)to 0.56 g/(m^(2)·a)with increasing depth from 600 m to 4850 m.A clear seasonal pattern of TMF was observed,with higher flux in summer than that in *** peak flux of 26.52 mg/(m^(2)·d)occurred in August at 600 m,while the lowest value of 0.07 mg/(m^(2)·d)was shown in February at 4850 *** settling particles at the deep layers had similar biochemical composition,with calcium carbonate(CaCO_(3))accounting for up to 90%,followed by organic matter and opal,characteristics of Carbonate *** POC flux decreased more rapidly in the twilight layer because of faster decomposition,remineralization,and higher temperature.A small fraction of POC was transported into the deep ocean by biological *** fluxes were mainly controlled by the calcareous ballasts besides the primary productivity of the surface *** advection may be another important factor affecting the flux in the seamount *** combination of settled matters rich in foraminiferal tests with topography and currents may be the reason for regulating the local abundance of benthos on *** results will fill in the knowledge gap of sedimentation flux,improve the understanding of ecosyste

关键词： sediment trap flux seamount POC Northwest Pacific Ocean

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Speciation,distribution,and potential ecological risk assessment of heavy metals in Xiamen Bay surface sediment

Speciation,distribution,and potential ecological risk assess...

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福建省海洋学会2014年学术年会暨福建省科协第十四届学术年会

作者： LIN Cai LIU Yang LI Wenquan sun xiuwu JI Weidong Third Institute of Oceanography State Oceanic Administration College of Ocean and Earth Science Xiamen University

Based on the survey of surface sediment in Xiamen Bay in October 2011, the speciation, distribution, and potential ecological risk assessment of heavy metals(Cu, Pb, Zn, Cd, and Cr) in this area were studied using the sequential extraction method and ecological risk assessment method. The results indicated:(1) the total concentrations of these heavy metals were influenced by runoff, industrial wastewater, and sewage, and were all higher in the coastal area than the offshore area while the highest area of Pb was a little farther away from the coastal water due to atmosphere deposition;(2) sequential extractions suggested that Cu was mainly composed with residual and Fe/Mn-oxide bound fractions, Pb was bound to Fe/Mn-oxide, Zn and Cr were dominated by residual, and Cd bound to exchangeable and carbonate fractions;(3) the order of migration and transformation sequence was Cd>Pb>Cu>Zn>Cr and the degree of pollution was Cd>Pb>Cu>Zn>Cr;and(4) the ratios of the secondary and primary phases showed that Zn and Cr were both clean, Cu may be polluted, Pb was moderately polluted, while Cd was heavily polluted.

关键词： Xiamen Bay heavy metals speciation distribution ecological risk

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将“数字革命”进行到底——上海数字印刷业“十二五”规划发展思路

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印刷杂志 2011年第1期 18-20页

作者：孙修吾上海数字印刷行业协会

"十二五"期间,上海数字印刷业应继续抓好张江数字出版基地和金山国家绿色创意示范园区项目,充分发挥文化大都市的特色优势,推进产业结构调整和优化升级,对接出版(书、报、刊),对接商务("四个率先"、"四个中心"),对接个性化需求(世界多... 详细信息

"十二五"期间,上海数字印刷业应继续抓好张江数字出版基地和金山国家绿色创意示范园区项目,充分发挥文化大都市的特色优势,推进产业结构调整和优化升级,对接出版(书、报、刊),对接商务("四个率先"、"四个中心"),对接个性化需求(世界多极化、人文多样化),着力整合资源,优化配置,促进数字印刷业快速发展,使上海成为世界第六大现代服务业城市群核心集聚地。

关键词：数字印刷标准化体系结构性调整

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腰英台油田注水见效规律分析

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油气藏评价与开发 2011年第4期1卷 40-43页

作者：杨正茂孙秀武中国石化华东分公司吉林项目部研究所吉林长春130062

腰英台油田为中低孔特低渗天然微裂缝发育油藏,通过对注水开发过程中油井见效见水的规律性总结,研究分析见效见水的主控因素是受裂缝及沉积微相的影响,注入水方向性推进特征明显。这一研究成果对指导油田下一步高效注水开发具有极其重... 详细信息

腰英台油田为中低孔特低渗天然微裂缝发育油藏,通过对注水开发过程中油井见效见水的规律性总结,研究分析见效见水的主控因素是受裂缝及沉积微相的影响,注入水方向性推进特征明显。这一研究成果对指导油田下一步高效注水开发具有极其重要意义。

关键词：特低渗透油藏注水开发裂缝沉积微相见效规律

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钦州湾沉积物中重金属的多元统计分析:空间关系、生态风险和来源识别

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应用海洋学学报 2024年第1期43卷 135-146页

作者：王伟力林彩刘洋黄海宁陈金民孙秀武林辉自然资源部第三海洋研究所福建厦门361005 广西北部湾海洋资源环境与可持续发展重点实验室广西北海536000

海湾是海洋和陆地相互作用和人类活动最强烈的区域,沉积物中重金属的含量和分布都受到人类活动的影响。为了探究钦州湾沉积物中重金属的含量水平、污染程度和可能来源,本研究分析了钦州湾表层沉积物中Cu、Pb、Zn、Cd、Cr、Hg和As的含量... 详细信息

海湾是海洋和陆地相互作用和人类活动最强烈的区域,沉积物中重金属的含量和分布都受到人类活动的影响。为了探究钦州湾沉积物中重金属的含量水平、污染程度和可能来源,本研究分析了钦州湾表层沉积物中Cu、Pb、Zn、Cd、Cr、Hg和As的含量及空间分布,采用地质累计指数(Igeo)和潜在生态风险指数(PERI)定量分析了重金属的污染程度和生态风险,并利用自组织映射(SOM)和正定矩阵因子分解法(PMF)模型评估了重金属的可能来源。结果表明:钦州湾表层沉积物重金属中Zn的平均含量最高,Hg平均含量最低;除个别站位的Pb含量符合海洋沉积物质量第二类标准外,其他重金属含量均符合海洋沉积物质量第一类标准;Igeo结果表明钦州湾表层沉积物主要的污染元素为Pb、Hg和Cu;PERI结果表明Hg是钦州湾表层沉积物主要的生态风险元素。SOM和PMF模型结果表明钦州湾表层沉积物重金属主要受自然来源、农业活动、工业生产活动的共同影响,各来源的相对贡献率分别为39.65%、29.15%和31.20%。

关键词：海洋化学表层沉积物重金属生态风险 PMF模型来源钦州湾

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