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science china Earth sciences 2010年第7期53卷 1008-1016页

作者： PI QingLing1,2,3 & HU JianYu1,2 1 state key laboratory of marine environmental science, xiamen university, xiamen 361005, china 2 Department of Oceanography, xiamen university, xiamen 361005, china 3 china Communications Construction Company First Harbor Consultants CO., LTD., Tianjin 300222, china 1. state key laboratory of marine environmental science Xiamen University Xiamen 361005 China2. Department of Oceanography Xiamen University Xiamen 361005 China3. China Communications Construction Company First Harbor Consultants CO. LTD. Tianjin 300222 China

A morphology-based edge detection method has been used to study sea surface temperature (SST) fronts in the Taiwan Strait and its adjacent area. The method is based on mathematical morphology with multi-dimensional and multi-structural elements. Using six years’ SST data from September 2002 to August 2008, we distinguished the large SST front like Kuroshio Front as well as the smaller ones: namely Taiwan Bank Front, Zhe-Min Coastal Front and Zhang-Yun Ridge Front. The seasonal and monthly variations of these fronts were also studied. Generally, the SST fronts are stronger in winter but weaker in summer. And the fronts are at their active stage during the period from January to May but at their declining stage during the period from July to October.

关键词： SST front remote sensing edge detection Taiwan Strait Kuroshio

Disequilibria between ^(210)Po and ^(210)Pb in surface waters of the southern South china Sea and their implications

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science china Earth sciences 2006年第1期49卷 103-112页

作者： YANG Weifeng, HUANG Yipu1,2, CHEN Min1,2, ZHANG Lei, LI Hongbin, LIU Guangshan1,2 & QIU Yusheng1,2 1. Department of Oceanography, xiamen university, xiamen 361005, china 2. state key laboratory of marine environmental science, xiamen university, xiamen 361005, china 1. Department of Oceanography Xiamen University Xiamen 361005 China 2. state key laboratory of marine environmental science Xiamen University Xiamen 361005 China

Activities of the naturally occurring radionuclides, ^(210)Pb and ^(210)Po,were measured in both dissolved ( 0.45 μm) phases from surfacewaters of the southern South china Sea. The average activity of particulate ^(210)Pb, 0.23 Bq/m^3 (n= 23), accounted for about 12% of the total ^(210)Pb, which corresponds with values of open *** ^(210)Po, with an average activity of 0.43 Bq/m^3, accounted for about 40% of the total^(210)Po, which was much higher than those of open and eutrophic oceans. The residence times oftotal ^(210)Po and ^(210)Pb in surface waters estimated from an irreversible steady-state model were0.82 a and 1.16 a, respectively. The consistently high fractionation factor calculated either byscavenging rate constants (5.42) or K_d values (6.69) suggested that a significant fractionationoccurred between ^(210)Po and ^(210)Pb during their removal from solution to particles and that thetwo radionuclides had different biogeochemical cycling pathways in the oligotrophic South china ***, our results indicated that there exist different fractionation mechanisms between^(210)Po and ^(210)Pb in different marine environments: in eutrophic ocean, plankton detritus andfecal pellets are the main carrier of ^(210)Po and ^(210)Pb, by which ^(210)Po and ^(210)Pb havebeen scavenged and removed; while in oligotrophic ocean, microbes could become the main carrier of^(210)Po and fractionate ^(210)Po and ^(210)Pb significantly as a result of scarce plankton detritusand fecal pellets. These results suggest the use of ^(210)Po to trace marine biogeochemicalprocesses relating to microbial activities and the cycling of sulfur group elements (S, Se, Te andPo).

关键词： South china Sea, 210Po, 210Pb, disequilibria, scavenging.

Impacts of increased atmospheric CO_2 concentration on photosynthesis and growth of micro-and macro-algae

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science china(Life sciences) 2008年第12期51卷 1144-1150页

作者： WU HongYan1, ZOU DingHui1 & GAO KunShan2 1 marine Biology Institute, Shantou university, Shantou 515063, china 2 state key laboratory of marine environmental science, xiamen university, xiamen 361005, china marine Biology Institute Shantou University Shantou 515063 China state key laboratory of marine environmental science Xiamen University Xiamen 361005 China

marine photosynthesis drives the oceanic biological CO2 pump to absorb CO2 from the atmosphere, which sinks more than one third of the industry-originated CO2 into the ocean. The increasing atmos-pheric CO2 and subsequent rise of pCO2 in seawater, which alters the carbonate system and related chemical reactions and results in lower pH and higher HCO3- concentration, affect photosynthetic CO2 fixation processes of phytoplanktonic and macroalgal species in direct and/or indirect ways. Although many unicellular and multicellular species can operate CO2-concentrating mechanisms (CCMs) to util-ize the large HCO3- pool in seawater, enriched CO2 up to several times the present atmospheric level has been shown to enhance photosynthesis and growth of both phytoplanktonic and macro-species that have less capacity of CCMs. Even for species that operate active CCMs and those whose photo-synthesis is not limited by CO2 in seawater, increased CO2 levels can down-regulate their CCMs and therefore enhance their growth under light-limiting conditions (at higher CO2 levels, less light energy is required to drive CCM). Altered physiological performances under high-CO2 conditions may cause genetic alteration in view of adaptation over long time scale. marine algae may adapt to a high CO2 oceanic environment so that the evolved communities in future are likely to be genetically different from the contemporary communities. However, most of the previous studies have been carried out under indoor conditions without considering the acidifying effects on seawater by increased CO2 and other interacting environmental factors, and little has been documented so far to explain how physi-ology of marine primary producers performs in a high-CO2 and low-pH ocean.

关键词： CO2 photosynthesis growth phytoplankton macroalgae

Impacts of CO_2-driven seawater acidification on survival,egg production rate and hatching success of four marine copepods

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Acta Oceanologica Sinica 2011年第6期30卷 86-94页

作者： ZHANG Dajuan LI Shaojing WANG Guizhong GUO Donghui College of Oceanography and environmental science Xiamen University Xiamen 361005 China state key laboratory of marine environmental science Xiamen University Xiamen 361005 China

Ecological experiments were conducted to examine the effects of seawater containing elevated par- tial pressure of carbon dioxide （p CO2 800 × 10 -6 , 2 000 × 10 -6 , 5 000 × 10 -6 and 10 000 × 10 -6 ） on the survival and reproduction of female Acartia pacifica, Acartia spinicauda, Calanus sinicus and Centropages tenuiremis, which are the dominant copepods in the southern coastal waters of china. The results show that the effects of elevated p CO2 on the survival rates of copepods were species-specific. C. sinicus, which was a macro-copepod, had a higher survival rate （62.01%–71.96%） than the other three species （5.00%–26.67%） during the eight day exposure. The egg production rates of C. sinicus, A. spinicauda and C. tenuiremis were significantly inhibited by the increased p CO2 and the exposure time duration. There were significantly negative impacts on the egg hatching success of A. spinicauda and C. tenuiremis in the p CO2 2 000 × 10 -6 and 10 000 × 10 -6 groups, and, in addition, the exposure time had noticeably impacts on these rates too. This study indicates that the reproductive performances of copepods were sensitive to elevated p CO2 , and that the response of different copepod species to acidified seawater was different. Furthermore, the synergistic effects of seawater acidification and climate change or other pollutant stresses on organisms should be given more attention.

关键词： CO2-driven acidification copepod survival reproductive performance

Concentration and distribution of 17 organochlorine pesticides (OCPs) in seawater from the Japan Sea northward to the Arctic Ocean

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science china Chemistry 2010年第5期53卷 1033-1047页

作者： CAI MingGang 1,2,QIU CanRong 1,SHEN Yuan 1,CAI MingHong 3,HUANG ShuiYing 1,QIAN BiHua 1,SUN JiongHui 1 & LIU XiaoYan 1 1Department of Oceanography,College of Oceanography and environmental science,xiamen university,xiamen 361005,china 2state key laboratory of marine environmental science,xiamen university,xiamen 361005,china 3state Oceanic Administration key laboratory for Polar science,Polar Research Institute of china,Shanghai 200136,china 1. Department of Oceanography College of Oceanography and Environmental Science Xiamen University Xiamen 361005 China2. State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China3. State Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of China Shanghai 200136 China

Seventeen classic organochlorine pesticides in surface seawater were studied in terms of their composition pattern as well as their distribution pattern in the areas covering the Japan Sea,Okhotsk Sea,Bering Sea,Chukchi Sea and Arctic *** concentrations varied,but roughly two levels were seen with one ranging between 0.1 and 1 ng L-1 for most HCH isomers and the other lower than 0.1 ng L-1 for other *** the 17 target compounds,HCHs were dominant with a total concentration percentage generally more than 50%,and a relatively high concentration percentage of heptachlor and aldrine was also observed at scattered *** historical long-term trend of several target chemicals in the five sea zones considered was discussed in comparison with previous ***-sea zone comparison was carried out for individual chemicals by comparing the concentration variation in all five sea zones.A higher variation in concentration was generally found in the northern sea zones,namely the Bering Sea,Chukchi Sea and Arctic Ocean,for most target *** sum concentration of the 17 target chemicals displayed a general trend of increasing northward from the Japan Sea to the Okhotsk Sea to the Bering Sea to the Arctic *** latitudinal trends were found forγ-HCH andγ-HCH,and the reason of this difference was discussed by considering their divergence of thermodynamic properties,which could contribute to a slightly different fractionation effect during their northward transport driven by atmospheric long range *** source of the HCHs was identified by analyzing theγ-HCH/γ-HCH ratio,which was less than 4 without exception,indicating a component characteristic featuring a mixture of technical HCHs and *** addition,the vertical distribution ofγ-HCH,γ-HCH and their ratio at station B80 was *** patterns were found in the upper 300 m while in layers from 300 m downward to 3500 m the patterns were fairly *** vertical p

关键词： organochlorine pesticides Arctic Ocean solid-phase extraction solid-phase microextraction

Study of colloidal phosphorus variation in estuary with salinity

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Acta Oceanologica Sinica 2010年第1期29卷 17-25页

作者： CHEN Ding ZHENG Airong CHEN Min Department of Oceanography and Institute of Subtropical Oceanography Xiamen University Xiamen 361005 China state key laboratory of marine environmental science. xiamen university Xiamen 361005. China

The variation of colloidal phosphorus with salinity in estuary was studied in this paper, which was compared with those of particle and truly dissolved phosphorus with the purpose of finding out the similarities and differences between their behaviors in the estuary. Distribution patterns of phosphorus in particle, colloidal and truly dissolved phase at different salinities and their relationships with suspended particulate matter were also studied to understand the transformation and transporta- tion of colloidal phosphorus in estuarine area. The result showed that the concentrations of total colloidal phosphorus, organic colloidal phosphorus and inorganic colloidall phosphate all descended from river-end to sea-end, illustrating their terrigenous source. *** of organic to total colloidal phosphorus decreased with salinity＇s increment, indicating that organic phosphorus was influenced by scavenging process of colloid more significantly as compared with inorganic phosphate. Both of the phosphorus variation tendencies and the proportion between organic and inorganic phosphorus in colloidal phase was similar with that in truly dissolved phase while different from that in particle phase.

关键词： truly dissolved phase colloidal phosphorus salinity

Buoyancy leads to high productivity of the Changjiang diluted water:a note

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Acta Oceanologica Sinica 2008年第6期27卷 133-140页

作者： CHEN Chen-Tung Arthur Institute of marine Geology and Chemistry National Sun Yat-sen University state key laboratory of marine environmental science Xiamen University

Being the mightiest river emptying into the East china Sea （ECS） and the Pacific Ocean, compounded with the large increase of nitrogen and phosphorus input due to anthropogenic activities, the Changjiang River （Yangtze River） has become a dominating source of these nutrients to the estuary. The high nutrient concentrations notwithstanding, however, outside of the estuary the high biological productivity of the Changjiang diluted water （CDW） are most probably fueled mainly by nutrient-rich subsurface waters originating from the upwelled Kuroshio waters. This is because while the buoyancy of the CDW spreads it out on the ECS continen- tal shelf, the CDW entrains subsurface waters along with the nutrients. Nutrients thus supplied are several times more than those supplied by the Changjiang River.

关键词： Changjiang River Changjiang diluted water nutrients Three Gorges Dam productivity buoyancy

Occurrence of gonadtropins like substance in the thoracic ganglion mass of the mud crab, Scylla paramamosain (Crustacea: Decapoda: Brachyura)

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Acta Oceanologica Sinica 2009年第5期28卷 76-80页

作者： YE Haihui HUANG Huiyang WANG Guizhong LI Shaojing Department of Oceanography ＆ Institute of Subtropical Oceanograpy Xiamen University Xiamen 361005 China state key laboratory of marine environmental science Xiamen University Xiamen 361005 China

The identification and localization of vertebrate follicle stimulating hormone （FSH） and luteinizing hormone （LH） in crustaceans may further elucidate the regulation mechanisms in arthropod repro-duction. Using immunocytochemical staining techniques, this study has localized vertebrate FSH-like and LH-like substances in neurons in the subesophageal and thoracic ganglia from the thoracic ganglion mass （TGM） of Scylla paramamosain （Crustacea： Decapoda： Brachyura）. Enzyme-linked immunosorbent assay （ELISA） has shown that the concentrations of both FSH-and LH-like sub-stances increased markedly in the TGM during the vitellogenic stage compared with that in the previtellogenic stage. These results indicate that substances resembling the vertebrate FSH and LH are present in S. paramamosain, and they may be involved in the development of the ovary as well as in ovulation.

关键词： follicle stimulating hormone (FSH) leuteinizing hormone (LH) Scylla paramamosain thoracic ganglion mass immunocytochemistry enzyme-linked immunosorbent assay (ELISA)

A preliminary study of the variation of phytoplankton absorption coefficients in the northern South china Sea

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Acta Oceanologica Sinica 2009年第5期28卷 17-29页

作者： WU Jingyu HONG Huasheng SHANG Shaoling DAI Minhan LEE Zhongping LI Shaojing state key laboratory of marine environmental science Xiamen University Xiamen 361005 China Department of Oceanography Xiamen University Xiamen 361005 China Naval Research Lab Code 7333 Stennis Space Center MS 39529 USA

The temporal and spatial variabilities of phytoplankton absorption coefficients （a ph （λ）） and their relationships with physical processes in the northern South china Sea were examined, based on in situ data collected from two cruise surveys during May 14 to 25, 2001 and November 2 to 21, 2002. Significant changes in the surface water in a ph values and B/R ratios （a ph （440）/a ph （675）） were observed in May, which were caused by a phytoplankton bloom on the inner shelf stimulated by a large river plume due to heavy precipitation. This is consistent with the observed one order of magnitude elevation of chlorophyll a and a shift from a pico/nano dominated phytoplankton community to one dominated by micro-algae. Enhanced vertical mixing due to strengthened northeast monsoon in November has been observed to result in higher surface a ph （675）（0.002–0.006 m-1 higher） and less pronounced subsurface maximum on the outer shelf/slope in November as compared with that in May. Measurements of a ph and B/R ratios from three transects in November revealed a highest surface a ph （675） immediately outside the mouth of the Zhujiang （Pearl） River Estuary, whereas lower a ph （675） and higher B/R ratios were featured in the outer shelf/slope waters, demonstrating the respective influence of the Zhujiang River plume and the oligotrophic water of the South china Sea. The difference in spectral shapes of phytoplankton absorption （measured by B/R ratios and bathochromic shifts） on these three transects infers that picoprocaryotes are the major component of the phytoplankton community on the outer shelf/slope rather than on the inner shelf. A regional tuning of the phytoplankton absorption spectral model （Carder et al., 1999） was attempted, demonstrating a greater spatial variation than temporal variation in the lead parameter a 0 （λ）. It was thus implicated that region-based parameterization of ocean color remote sensing algorithms in the northern South china Sea was mandatory.

关键词： phytoplankton absorption coefficient variation picoprokaryotes parameterization South china Sea

Influence of particle composition on thorium scavenging in the marginal china seas

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Acta Oceanologica Sinica 2009年第2期28卷 45-53页

作者： YANG Weifeng CHEN Min CAO Jianping QIU Yusheng ZHANG Run MA Qiang TONG Jinlu YANG Junhong YANG Zhi LUE E Department of Oceanography Xiamen University Xiamen 361005 China state key laboratory of marine environmental science Xiamen University Xiamen 361005 China

Thorium-234 and particle composition （organic matter, biogenic silica, carbonate and lithogenic component） were examined in the East china Sea （ECS） and the northern South china Sea （NSCS） in order to constrain the particle types scavenging thorium isotopes. Good positive correlations between particulate organic matter （POM） or carbonate and thorium-234 in suspended particulate matter （SPM） indicates that POM and carbonate are efficient to scavenge thorium-234. No relationship between biogenic silica and thorium-234 suggests that geochemical behavior of thorium-234 may be not influenced by biogenic silica. A simple model was used to evaluate the affinity of thorium-234 to different particle components. The results show that POM is the most efficient scavenger for thorium-234 in the ECS and the NSCS, followed by carbonate. The authors＇ results lend support to the utility of thorium-234 as a proxy of POC and carbonate in the upper layer. However, the strong dependence of thorium scavenging on particle composition challenges thorium-230 as a constant flux proxy.

关键词： POC biogenic silica thorium carbonate particle composition