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Chinese Journal of Oceanology and Limnology 2010年第2期28卷 315-322页

作者：孙静于志刚高亚辉周茜茜甄毓陈洪涛赵丽媛姚庆祯米铁柱 College of marine Life Sciences Ocean University of China key laboratory of marine Chemistry Theory and Technology Ministry of Education Ocean University of China School of Life Sciences Xiamen University key laboratory of marine environment and ecology Ministry of Education Ocean University of China

Relationships between phytoplankton community composition and environmental variables in the East China Sea (ECS) and Yellow Sea (YS) were investigated using geochemical and molecular microbiology methods. The diversity of phytoplankton was characterized using cultivation-independent PCR-based denaturing gradient gel electrophoresis (DGGE). Groups resulting from unweighted pair-group method with arithmetic averages clustering of the DGGE profiles showed good consistency with the eco-environmental characteristics of the sea area they belonged to. Additionally, the clustering results based on DGGE fingerprinting and those based on morphological compositions were practically identical. The relationship of phytoplankton diversity to environmental factors was statistically analyzed. Temperature, dissolved inorganic nitrogen (DIN), and silicate-Si were found significantly related to the phytoplankton community composition. Canonical correspondence analysis (CCA) was performed to reveal the relationship between community composition and these three environmental factors. Generally, values of the ECS are clearly separated from those of the YS in the CCA biplot, due to mainly the effect of temperature and DIN.

关键词： canonical correspondence analysis (CCA) denaturing gradient gel electrophoresis (DGGE) phytoplankton East China Sea Yellow Sea

Effect of decreasing temperature on the strobilation of Aurelia sp.1

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Journal of Oceanology and Limnology 2018年第2期36卷 465-472页

作者： SHI Yan YU Zhigang ZHEN Yu WANG Guoshan WANG Xungong MI Tiezhu College of environmental Science and Engineering Ocean University of China Qingdao 266100 China key laboratory of marine environment and ecology Ministry of Education Qingdao 266100 China laboratory for marine ecology and environmental Science Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China key laboratory of marine Chemistry Theory and Technology Ministry of Education Qingdao 266100 China

The worldwide proliferation of marine jellyfish has become a crucial ecological and social issue, and as a cosmopolitan species, Aurelia spp. have received increasing scientific attentions. In the present study, the responses of strobilation in Aurelia sp. 1 to decreasing temperature were illuminated through the expression levels of the retinoid x receptor （RxR） gene and the gene encoding a secreted protein, CL390. We observed that a higher final temperature decreased the strobilation prophase and strobilation interphase periods, and the growth rate of the strobilae ratio increased with increasing CL390 gene expression. The ratio of strobilae at 12~C was highest, and the strobilae showed the higher releasing ratios at both 12℃ and 16℃ compared with those at 4℃ and 8℃. Furthermore, more ephyrae were released at the higher final temperature. Additionally, up-regulation and down-regulation of the CL390 gene were observed in response to the four decreasing temperatures. Although the four CL390 gene transcript levels increased more significantly than the transcript levels of the RxR gene, similar trends were observed in both genes.

关键词： moon jellyfish strobila retinoid x receptor(RxR) CL390

Chemical Mechanism of Flocculation and Deposition of Clay Colloids in Coastal Aquifers

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Journal of Ocean University of China 2016年第5期15卷 847-852页

作者： ZHOU Jun QIU Lixia LIN Guoqing YAN Xiaoyun CHEN Xiaolan PANG Honglu College of environment and Safety Engineering Qingdao University of Science & Technology key laboratory of marine environment and ecology Ministry of Education Ocean University of China

Seawater intrusion has become one of serious environmental problems in coastal areas. During the replacement of saline water by fresh water in the aquifers, in-situ clay could be released, transport and deposit in the porous media due to the change of hydrodynamic and geochemical conditions, which resulted in the increasing of particle size, plugging of pores and reduction of the permeability. Batch experiments and sand column experiments were explored to study the relationships between the flocculation of in-situ clay and geochemical conditions, by changing ionic strength and ionic type of clay suspension. Column outflow was analyzed for suspended particles and electrical conductivity. The total percentage of colloid straining and interception distribution in porous media was calculated. The results indicate that porous media had an effect on the interception of clay colloid particles with about 10 percent clay colloids captured due to the rough surfaces and spatial structure of porous media. Ionic strength played a key role on the permeability reductions. The higher ionic strength is, the greater the amount of colloidal particles trapped. Ionic type also had a significant effect on the interception of clay colloid particles. Ripening was the main mechanism for the interception within porous media when the bulk solution was potassium chloride while blocking happened when the bulk solution was sodium chloride. The distribution of clay colloids in porous media was heterogeneous. The closer to the sand column inlet was the less interception of clay colloids was. The results can provide the scientific basis for preventing the water sensitivity during the process of salty aquifer restoration.

关键词： permeability geochemical porous colloid closer intrusion effluent pores Ionic suspended

A laboratory Column Study on Particles Release in Remediation of Seawater Intrusion Region

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Journal of Ocean University of China 2015年第6期14卷 1013-1018页

作者： ZHOU Jun LIN Guoqing LIU Jianbo ZHANG Peidong GONG Lei College of environment and Safety Engineering Qingdao University of Science and Technology key laboratory of marine environment and ecology Ministry of EducationOcean University of China

In coastal areas, excessive exploitation of groundwater causes seawater intrusion. In artificial recharge of aquifer remediation process, the replacement of saltwater and freshwater with each other causes colloid release, and permeability also decreases. In this paper, the aquifer samples containing minimal clay mineral(mainly illite) in Dagu River aquifer were used. Adopting horizontal column experiments, we studied the influences of seepage velocity and ionic strength on particle release, as well as the relationship between them. In the column experiments, the Critical Salt Concentration(CSC) of the Dagu River aquifer was determined as 0.05 mol L^(-1) approximately. This result was basically consistent with the DLVO theoretical calculation. For the constant seepage velocity, the salinity descending rate and partical release were slower, and the peak of particle concentration was lower. However, the total amount of released particles was almost constant at different salinity descending rate. For constant salinity descending rates, the peak of particle concentration decreased as seepage velocity increased, but the total amount of released particles rose up. The experiments also indicated the existence of a critical seepage velocity, which dropped with the decrease of salt concentration. When the concentration of Na Cl solution decreased from 0.17 mol L^(-1) to 0.06 mol L^(-1), the critical seepage velocity decreased from 3 cm min^(-1)to 2.5 cm min^(-1), which is consistent to the results predicted by DLVO theory.

关键词： seawater intrusion particles release critical salt concentration salinity descending rate critical seepage velocity

Application of Stable Isotope Tracing Technologies in Identification of Transformation among Waters in Sanjiang Plain,Northeast China

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Chinese Geographical Science 2013年第4期23卷 435-444页

作者： XU Yingying YAN Baixing LUAN Zhaoqing ZHU Hui WANG Lixia key laboratory of Songliao Auquatic environment Ministry of Education key laboratory of Wetland ecology and environment Northeast Institute of Geography and AgroecologyChinese Academy of Sciences

In order to investigate the transformation among the precipitation,groundwater,and surface water in the Sanjiang Plain,Northeast China,precipitation and groundwater samples which were collected at the meteorological station of the Sanjiang Mire Wetland Experimental Station,Chinese Academy of Sciences and the surface water which collected from the Wolulan River were used to identify the transformation of three types of *** isotope composition of different kinds of water sources were analyzed via stable isotope(deuterium and oxygen-18) investigation of natural *** results show a clear seasonal difference in the stable isotopes in *** the cold half-year,the mean stable isotope in precipitation in the Sanjiang Plain reaches its minimum with the minimum *** δ18O and δD values are high in the rainy *** the Wolulan River,the evaporation is the highest in August and *** volume of evaporation and the replenishment to the river is mostly *** groundwater is recharged more by the direct infiltration of precipitation than by the river *** results of this study indicate that the water bodies in the Sanjiang Plain have close hydrologic relationships,and that the transformation among each water system frequently occurs.

关键词： hydrogen and oxygen stable isotopes groundwater precipitation water cycle recharge

Molecular Characterization of Sulfate-Reducing Bacteria Community in Surface Sediments from the Adjacent Area of Changjiang Estuary

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Journal of Ocean University of China 2016年第1期15卷 107-116页

作者： ZHANG Yu ZHEN Yu MI Tiezhu HE Hui YU Zhigang College of environmental Science and Engineering Ocean University of China key laboratory of marine environment and ecology Ministry of Education Function laboratory for marine ecology and environmental Science Qingdao National Oceanography Laboratory College of marine Life Sciences Ocean University of China key laboratory of marine Chemical Theory and Technology Ministry of Education

Sulfate-reducing bacteria(SRB),which obtain energy from dissimilatory sulfate reduction,play a vital role in the carbon and sulfur *** dissimilatory sulfite reductase(Dsr),catalyzing the last step in the sulfate reduction pathway,has been found in all known SRB that have been tested so *** this study,the diversity of SRB was investigated in the surface sediments from the adjacent area of Changjiang Estuary by PCR amplification,cloning and sequencing of the dissimilatory sulfite reductase beta subunit gene(dsr B).Based on dsr B clone libraries constructed in this study,diversified SRB were found,represented by 173 unique *** cloned sequences were associated with Desulfobacteraceae,Desulfobulbaceae,and a large fraction(60%) of novel sequences that have deeply branched groups in the dsr B tree,indicating that novel SRB inhabit the surface *** addition,correlations of the SRB assemblages with environmental factors were analyzed by the linear model-based redundancy analysis(RDA).The result revealed that temperature,salinity and the content of TOC were most closely correlated with the SRB *** information on SRB community was obtained by applying the utility of Uni Frac to published dsr B gene sequences from this study and other 9 different kinds of marine *** results demonstrated that there were highly similar SRB genotypes in the marine and estuarine sediments,and that geographic positions and environmental factors influenced the SRB community distribution.

关键词： sulfate-reducing bacteria (SRB) dissimilatory sulfite reductase beta subunit gene (dsrB) diversity

Release of Mercury from Intertidal Sediment to Atmosphere in Summer and Winter

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Chinese Geographical Science 2010年第2期20卷 99-105页

作者： LIU Ruhai Under the auspices of National Natural Science Foundation of China （No. 40806045） the Program of the State Bureau of Oceanic Administration （No. 908-02-02-03） WANG Yan SHAN Changqing Ling Min SHAN Hongxian ministry of education key laboratory of marine environment and ecology Ocean University of China Qingdao 266100 China Department of Urban and environment Binzhou Universtiy Binzhou 256600 China

The release of mercury from intertidal sediment to atmosphere was studied based on the simulated experiment. The experiment samples were collected from the Haibo Estuary (S1) and the Licun Estuary (S2) of the Jiaozhou Bay in China,which are seriously polluted with mercury. The results show that the mercury in sediment releases rapidly to atmosphere under solar radiation. After 8 hours of solar radiation,mercury concentrations decrease from 5.62 μg/g and 2.92 μg/g to 2.34 μg/g and 1.39 μg/g in S1 and S2 sediments respectively in summer,and decrease from 5.62 μg/g and 2.92 μg/g to 4.58 μg/g and 2.13 μg/g respectively in winter. The mercury species in the sediment change markedly under solar radiation. The concentrations of mercury bound to organic matter decrease significantly from 2.73 μg/g to 0.31 μg/g in S1 and from 2.07 μg/g to 0.31 μg/g in S2,and the released mercury mainly comes from mercury bound to organic matter. Mercury flux shows distinguishing characteristic of diurnal change,and it increases rapidly in the morning with the rising of solar radiation intensity,but decreases in the afternoon. The mercury flux increases with sediment temperature and solar radiation intensity. The rapid release of mercury in intertidal sediment plays an important role in the regional mercury cycle.

关键词： mercury intertidal sediment mercury release solar radiation mercury species

The failure propagation of weakly stable sediment:A reason for the formation of high-velocity turbidity currents in submarine canyons

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Journal of Oceanology and Limnology 2023年第1期41卷 100-117页

作者： Yupeng REN Yi ZHANG Guohui XU Xingbei XU Houjie WANG Zhiyuan CHEN Shandong Provincial key laboratory of marine environment and Geological Engineering Qingdao 266100China Shandong Provincial key laboratory of marine environment and Geological Engineering Ocean University of ChinaQingdao 266100China key laboratory of marine environment and ecology Ocean University of ChinaMinistry of EducationQingdao 266100China

The long-distance movement of turbidity currents in submarine canyons can transport large amounts of sediment to deep-sea *** studies show obvious differences in the turbidity current velocities derived from the multiple cables damage events ranging from 5.9 to 28.0 m/s and those of field observations between 0.15 and 7.2 m/***,questions remain regarding whether a turbid fluid in an undersea environment can flow through a submarine canyon for a long distance at a high speed.A new model based on weakly stable sediment is proposed(proposed failure propagation model for weakly stable sediments,WS S-PFP model for short)to explain the high-speed and long-range motion of turbidity currents in submarine canyons through the combination of laboratory tests and numerical *** model is based on two mechanisms:1)the original turbidity current triggers the destabilization of the weakly stable sediment bed and promotes the destabilization and transport of the soft sediment in the downstream direction and 2)the excitation wave that forms when the original turbidity current moves into the canyon leads to the destabilization and transport of the weakly stable sediment in the downstream *** proposed model will provide dynamic process interpretation for the study of deep-sea deposition,pollutant transport,and optical cable damage.

关键词： turbidity current excitation wave dense basal layer velocity WSS-PFP model

Macrobenthic Community in the Xiaoqing River Estuary in Laizhou Bay,China

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Journal of Ocean University of China 2013年第3期12卷 366-372页

作者： LUO Xianxiang ZHANG Shanshan YANG Jianqiang PAN Jinfen TIAN Lin ZHANG Longjun key laboratory of marine environmental Science and ecology of the ministry of education Ocean University of China Shandong Provincial key laboratory of marine ecology and environment & Disaster Prevention and Mitigation key laboratory of marine Oil Spill Identification and Damage Assessment Technology SOA

The macrobenthic community of the Xiaoqing River Estuary and the adjacent sea waters was investigated in May and November 2008,August 2009,and May and September 2010,respectively.A total of 95 species of macrobenthos were identified in the five cruises and most of them were polychaetes(46.39%),mollusks(28.86%) and crustaceans(20.62%).The Shannon-Wiener index of macrobenthos was lower than 2 in 67% *** the stream channel,estuary and the coastal waters,the species of polychaetes reduced gradually,while the abundance increased at first and then *** abundance was the biggest at regions with salinity of 5 20 in the *** species and abundance of mollusks and crustaceans increased *** for seasonal distribution,the species,abundance and biomass were higher in spring and lower in summer and *** compared with Laizhou Bay and Yellow River Estuary,the species of macrobenthos appeared in the Xiaoqing River Estuary were much less,while the percentage of polychaetes was *** and biomass were higher in Xiaoqing River estuary,then consequently followed by Laizhou Bay and Yellow River *** dominant species in Xiaoqing River Estuary was polychaete,and Layzhou Bay *** community structure characteristics of macrobenthos in the Xiaoqing River Estuary revealed a significant pollution status in this region.

关键词： Xiaoqing River Estuary Laizhou Bay macrobenthos community structure characteristics

The modification and optimizing of the CHEMTAX running in the South China Sea

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Acta Oceanologica Sinica 2015年第2期34卷 124-131页

作者： WANG Lei HUANG Bangqin LIU Xin XIAO Wupeng Fujian Provincial key laboratory for Coastal ecology and environmental Studies/key laboratory of Coastal and Wetland Ecosystems of ministry of education College of the Environment and Ecology Xiamen University

In order to determine the phytoplankton community composition, the modification and optimizing of the CHEMical TAXonomy（CHEMTAX） running was carried out through samples grouping, successive run and evaluate the results for HPLC-pigment samples in the South China Sea（SCS）. The vertical distribution of the ratio of pigment to total Chl a（TChl a） exhibited three different patterns, including increasing with depth pattern（e.g., But-Fuco）, decreasing with depth pattern（e.g., Zea） and increasing at deep chlorophyll maximum（DCM） pattern（e.g., Hex-Fuco）. The vertical profiles for Fuco/TChl a and Pras/TChl a was higher in coast than in the shelf and basin, and the Zea and Dv-Chl a expressed conversely. So the samples in the coastal stations must be separated for the cluster analysis group procedure in the SCS. Successive run was introduced into the CHEMTAX calculation and the output results were evaluated by the convergence of pigment/TChl a ratios. Most of the ratios were well converged at the fifth running, except Zea/TChl a for Prochlorococcus and Chl b/TChl a for prasinophytes and so on. To evaluate the fifth running＇s results, haptophytes_8 and chlorophytes were two phytoplankton groups with much uncertainty. But the fifth estimated value was better than running once was supported by the regression evidence between the measured pigment concentration and calculation values. Synechococcus was another component with much mutability, and the CHEMTAX＇s result should be compared to the flow cytometry＇s cell abundance.

关键词： phytoplankton CHEMTAX pigment/Chl a ratio successive run South China Sea