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From Teacher-Education University to Comprehensive University:Case Studies of East China Normal University,Southwest University and Yanbian University 被引量:2
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作者 LI Mei 《Frontiers of Education in China》 2010年第4期507-530,共24页
Three different“logics”—that of the internal strategies of the institutions,the economic pressures of the socialist market economy and the political policies of the state drive the development of a university.The d... Three different“logics”—that of the internal strategies of the institutions,the economic pressures of the socialist market economy and the political policies of the state drive the development of a university.The dynamic interaction and coexistence of the three logics has determined the transformation models of teacher-education or normal universities in China.This paper aims at describing and analyzing both the process and the forces that led to these transformations by taking East China Normal University(ECNU),Southwest University(SWU)and Yanbian University(YBU)as examples.Reliance on government and market resources has put these universities into a dilemma:On the one hand,they wanted to retain their original features so as to preserve their leading position in the“teacher education”market,and on the other,they needed to merge,expand,restructure and enhance their quality as they pursued overall development.The case analyses show that the teacher-education university’s need for self-development,which is the internal determinant,plays a critical role in its transformation.At the same time,the socioeconomic environment and national policies influence the institution while it displays considerable capacity for self-adjustment. 展开更多
关键词 normal/teacher-education universities COMPREHENSIVENESS East China Normal University(ECNU) Southwest University(SWU) Yanbian University(YBU)
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Multiple grain-size fraction analysis of heavy minerals and the provenance identification of sediments from the abandoned Huanghe River,eastern China
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作者 Mengyao WANG Bingfu JIN Jianjun JIA 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期921-935,共15页
The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research.The characteristics of heavy minerals,combined with the geochemical constituents of detrita... The quantitative analysis of sediment sources in a sink is an important scientific topic and challenge in provenance research.The characteristics of heavy minerals,combined with the geochemical constituents of detrital grains,provide a reliable provenance-tracing approach.We developed a mineral identification method to analyze the multiple grain-size fraction of sediments,from which the elemental geochemistry of hornblende was used to compare the characteristics of sediments from the Huaihe River and Huanghe(Yellow)River in eastern China.Elements that were statistically identified as being able to discriminate sediment provenance were employed to perform a quantitative analysis of the sources of sediments of the abandoned Huanghe River.Results reveal that the Huaihe River is characterized by a high amphibole content of>60%and that the Huanghe and abandoned Huanghe rivers have greater abundances of limonite and carbonate minerals compared with those of the Huaihe River.The contents of trace elements and rare earth elements in hornblende show that the sediments of the abandoned Huanghe River are similar to those of the Huanghe River but different from those of the Huaihe River.Furthermore,chemical mass balance was used to calculate the relative contributions of different provenances of sediment from the abandoned Huanghe River,and nine trace elements of hornblende were identified as discriminators of provenance.Approximately 2%of the hornblende in the abandoned Huanghe River is derived from the Huaihe River and 98%from the Huanghe River.Considering the proportion of hornblende in the total sediment,it is inferred that the contribution of Huaihe River sediment to the abandoned Huanghe River is approximately 0.5%.This study shows that mineral analysis using multiple grain-size fractions(within the wide range of 1Φto 6Φ)with assessment in elemental geochemistry of hornblende can characterize the provenance of fluvial material in coastal zones. 展开更多
关键词 quantitative provenance analysis heavy mineral multiple grain-size fraction HORNBLENDE elemental geochemistry fluvial sediment the abandoned Huanghe River
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Distribution of benthic macrofaunal communities in intertidal flat under hydrodynamic influence:a case study of Jiangsu coast,East China
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作者 Longhui ZHANG Dezhi CHEN +3 位作者 Shu GAO Yaping WANG Benwei SHI Yongfen DU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第3期1024-1038,共15页
To identify the distribution pattern of macrofaunal assemblages of the Dafeng intertidal flats in response to hydrodynamic and sediment dynamic processes in the northern Jiangsu coast,East China,macrofauna sampling an... To identify the distribution pattern of macrofaunal assemblages of the Dafeng intertidal flats in response to hydrodynamic and sediment dynamic processes in the northern Jiangsu coast,East China,macrofauna sampling and hydrodynamic observations were carried out simultaneously across the mud flat,mixed mud-sand flat,and silt-sand flat of the intertidal zone in June 2018.Results show that there was a clear zonal distribution pattern of the macrofaunal communities,as is controlled by local hydrological and sedimentary environments.Principal component analysis(PCA)revealed three types of intertidal area in terms of hydrological and surficial sediment parameters.Similarly,three distinct groups of the macrofaunal communities,i.e.,mud flat,mix mud-sand,and silt-sand groups,were recognized at similarity level of 24%based on the CLUSTER analysis in similarity profile(SIMPROF)test.Correlation analysis upon best variables stepwise search(BVSTEP)indicated the importance of the hydrodynamics(e.g.,water temperature and salinity,tidal duration,flow speed,suspended sediment concentration,and wave height)in the differentiation of macrofaunal communities with different taxonomic classes over the intertidal zone.Therefore,macrofaunal assemblages,similar to hydrology and surficial sediment,have a unique zonation pattern.Small-sized deposit feeders adapt better to low energy environments,thus dominated the upper part of the intertidal flat,whilst the heavy and large-sized filter feeders and deposit feeders were dominant over the middle and lower parts.The hydrodynamic and sediment processes cause biota-niche separation,which affected the biological processes across the intertidal flat. 展开更多
关键词 macrofaunal communities hydrodynamic process inter-tidal ecosystem SEDIMENTATION tidal flat Jiangsu coast
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The influence of lipid-extraction on theδ^(13)C of mesopelagic and demersal fish in the South China Sea:modification and application of lipid normalization models
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作者 Linyu Wang Fuqiang Wang +1 位作者 Zuozhi Chen Ying Wu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第1期35-43,共9页
Mesopelagic fish,the most important daily vertically migrating community in the oceans,are characterized by high lipid content which may obscure the interpretation of stable isotopes analysis.Demersal fish,which are i... Mesopelagic fish,the most important daily vertically migrating community in the oceans,are characterized by high lipid content which may obscure the interpretation of stable isotopes analysis.Demersal fish,which are important consumers in the food web dominated by mesopelagic fish,also have a high lipid content.Here we collected 127 fish samples from the South China Sea and evaluated the effect of lipid contents on△δ^(13)C of mesopelagic and demersal fish.In lipid-extracted mesopelagic fish,the C/N content ratio(<5.5)shows a clear correlation withΔδ^(13)C(the offset of bulk and lipid-extractedδ^(13)C values),especially in non-migratory and semi-migratory species;these values were less correlation in demersal fish.Based on our results,we suggest that mesopelagic and demersal fish in different regions of the South China Sea should be studied separately using appropriate correction models and less fit for the traditional model.Moreover,the C/N content ratio should be used cautiously for establishing the lipid normalization model,especially for the fish in migratory mesopelagic fish and demersal fish.Our results also reveal that mesopelagic fish across nearby regions could be analyzed together.The new models described here can be applied in future studies of mesopelagic and demersal fish in the South China Sea. 展开更多
关键词 mesopelagic fish demersal fish lipid normalization model C/N content ratio lipid content δ13C South China Sea
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Patterns and drivers of avian taxonomic and phylogenetic beta diversity in China vary across geographical backgrounds and dispersal abilities
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作者 Jian-Chao Liang Zhi-Feng Ding +7 位作者 Chun-Lin Li Yi-Ming Hu Zhi-Xin Zhou Gan-Wen Lie Xiao-Nan Niu Wen-Bin Huang Hui-Jian Hu Xing-Feng Si 《Zoological Research》 SCIE CSCD 2024年第1期125-135,共11页
Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity studies.Here,we examined whethe... Geographical background and dispersal ability may strongly influence assemblage dissimilarity;however,these aspects have generally been overlooked in previous large-scale beta diversity studies.Here,we examined whether the patterns and drivers of taxonomic beta diversity(TBD)and phylogenetic beta diversity(PBD)of breeding birds in China vary across(1)regions on both sides of the Hu Line,which demarcates China’s topographical,climatic,economic,and social patterns,and(2)species with different dispersal ability.TBD and PBD were calculated and partitioned into turnover and nestedness components using a moving window approach.Variables representing climate,habitat heterogeneity,and habitat quality were employed to evaluate the effects of environmental filtering.Spatial distance was considered to assess the impact of dispersal limitation.Variance partitioning analysis was applied to assess the relative roles of these variables.In general,the values of TBD and PBD were high in mountainous areas and were largely determined by environmental filtering.However,different dominant environmental filters on either side of the Hu Line led to divergent beta diversity patterns.Specifically,climate-driven species turnover and habitat heterogeneity-related species nestedness dominated the regions east and west of the line,respectively.Additionally,bird species with stronger dispersal ability were more susceptible to environmental filtering,resulting in more homogeneous assemblages.Our results indicated that regions with distinctive geographical backgrounds may present different ecological factors that lead to divergent assemblage dissimilarity patterns,and dispersal ability determines the response of assemblages to these ecological factors.Identifying a single universal explanation for the observed pattern without considering these aspects may lead to simplistic or incomplete conclusions.Consequently,a comprehensive understanding of large-scale beta diversity patterns and effective planning of conservation strategies necessitate the consideration of both geographical background and species dispersal ability. 展开更多
关键词 Beta diversity Environmental filtering Dispersal limitation Hu Line Species dispersal ability Breeding birds
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Chemical and spectroscopic characterization of dissolved humic substances in a mangrove-fringed estuary in the eastern coast of Hainan Island,China 被引量:7
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作者 张耀玲 杜金洲 +3 位作者 彭浡 张芬芬 赵欣 张经 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第2期454-463,共10页
Mangrove-derived dissolved organic matter(DOM) has an important effect on estuarine and coastal area on a large scale.In order to improve the understanding of origin,composition,and fate of DOM in mangrove-fringed est... Mangrove-derived dissolved organic matter(DOM) has an important effect on estuarine and coastal area on a large scale.In order to improve the understanding of origin,composition,and fate of DOM in mangrove-fringed estuarine and coastal areas,dissolved humic substances(DHS) were isolated from one mangrove pore-water sample and one near-shore seawater sample downstream the mangrove pore-water site in the eastern coast of Hainan Island,South China.Fulvic acids,humic acids and XAD-4 fractions were obtained from the two water samples by using a two-column array of XAD-8 and XAD-4 resins.Chemical and spectroscopic methods were used to analyze the features of these DHS.Compared to the mangrove pore-water DHS,the near-shore seawater DHS were found rich in 13 C with lower C/N ratios and more aliphatic compounds and carbohydrates,but less aromatic structures and carboxyl groups.As for the three fractions of the two DHS,XAD-4 fractions contain more aliphatics,carbohydrates,carboxyl groups,and enrich in 13 C with respect to both fulvic and humic acids.Photo-oxidation transformation and contribution from marine-derived DOM were considered as the main reasons resulted in the difference in compositional features for these DHS in this study. 展开更多
关键词 溶解有机物 中国海南岛 东部沿海 红树林 光谱特性 腐殖物质 河口 环绕
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Impact of the eastern water diversion from the south to the north project on the saltwater intrusion in the Changjiang Estuary in China 被引量:10
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作者 XU Kun ZHU Jianrong GU Yuliang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2012年第3期47-58,共12页
The south to the north project (WDP) on the saltwater intrusion in the Changjiang Estuary is studied by the improved three-dimensionai (3D) numerical model.The net unit width flux in the Changjiang Estuary as well as ... The south to the north project (WDP) on the saltwater intrusion in the Changjiang Estuary is studied by the improved three-dimensionai (3D) numerical model.The net unit width flux in the Changjiang Estuary as well as the sectional salt flux is calculated in the North Branch (NB),the South Branch (SB),the North Channel (NC),the South Channel (SC),the North Passage (NP) and the South Passage (SP),respectively.The net seaward water flux in the SB is reduced,and the net water flux spilling over from the NB to the SB is enhanced after the eastern WDP.Under the mean river discharge condition in the dry season,the net salt flux spilling over from the NB to the SB is increased by 2.09 t/s and 0.52 t/s during the spring and neap tides,respectively,due to the eastern WDP.The saltwater intrusion in the Changjiang Estuary is enhanced by the eastern WDP.Compared with that during the spring tide,the net water diversion ratio during the neap tide in the NC is smaller,and thus the enhancement of the saltwater intrusion by the eastern WDP is smaller in the NC,and larger in the NP and the SP.The tidally averaged surface salinity at the water intakes of the Dongfengxisha Reservoir,the Chenhang Reservoir and the Qingcaosha Reservoir rises both during the spring and neap tides. 展开更多
关键词 eastern water diversion from the south to the north project saltwater intrusion Changjiang Estuary numerical calculation the water resource
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Spatial Impact of High-speed Railway on the Urban Scale:An Empirical Analysis from Northeast China 被引量:5
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作者 WANG Shaobo GUO Jianke +2 位作者 LUO Xiaolong LIU Junfeng GU Zongni 《Chinese Geographical Science》 SCIE CSCD 2020年第2期366-378,共13页
The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to eit... The emergence of rapid transit,primarily represented by high-speed railway(HSR),while reshaping the regional traffic patterns,leads to the reconstruction and redistribution of population and industry.This leads to either shrinkage or expansion of urban scale.However,research on the influence mechanisms of the urban scale has mostly concentrated on historical,economic and social factors.The influence of traffic factors is rarely mentioned in current research.Therefore,this study examines Northeast China,where the change in urban scale is most significant,to discuss the spatial impact of high-speed railway on the urban scale.This is of great significance in terms of enriching current understanding of the factors affecting the urban scale.The results included the following:1)The high-speed railway produced considerable space-time convergence effects,however,simultaneously aggravated the imbalance in traffic development in Northeast China.The increase in accessibility presents attenuation characteristics from the high-speed railway.Additionally,the high-speed railway has changed the mode of cooperation between cities in the provinces,inter-regional and inter-provincial cooperation models gradually become popular.2)The change rate of accessibility and the urban scale present significant spatial coupling phenomena,with the change rate of the Harbin-Dalian trunk lines and its surroundings being more significant.3)There are predominantly four modes of the influence of high-speed railway on the urban scale,which make difference city present expansion or shrinkage. 展开更多
关键词 high-speed railway urban scale traffic ACCESSIBILITY SPATIAL coupling GWR model
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The Distribution of Dissolved Aluminum in the Yellow and East China Seas 被引量:5
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作者 LI Jianbing REN Jingling +1 位作者 ZHANG Jing LIU Sumei 《Journal of Ocean University of China》 SCIE CAS 2008年第1期48-54,共7页
Water samples containing dissolved aluminum were collected from the Yellow and East China Seas in Octo- ber-November 2000. The average concentrations of dissolved Al in the Yellow Sea (YS) and East China Sea (ECS) wer... Water samples containing dissolved aluminum were collected from the Yellow and East China Seas in Octo- ber-November 2000. The average concentrations of dissolved Al in the Yellow Sea (YS) and East China Sea (ECS) were 0.042 and 0.056 μmolL-1, respectively. The concentration of dissolved aluminum decreased gradually across the continental shelf. The lower concentrations appeared in the YS cold water center and in the bottom layer at the shelf edge of the ECS, where they were 0.016 and 0.011 μmolL-1, respectively. The distribution of dissolved Al was controlled by physical mixing processes rather than biological up- take processes. The impact of different water masses along the PN transect was calculated based on the mass balance model. The results show that the impact of the Changjiang River was mainly concentrated on the coastal area and the top thermocline water on the ECS shelf, where the impact percentage decreased from 12.6% to 1.1% in the surface water, while the contribution of the Ku- roshio water was dominant on the ECS shelf in this survey, increasing from 77.6% to 97.8% along the PN transect from the Changjiang River Estuary to the Ryukyu Islands. It is concluded that aluminum can serve as a proper tracer for studying the impact of Changjiang terrestrial matter on the ECS shelf water. 展开更多
关键词 东海 黄海 分布状况 长江 可分解铝
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Bacterial diversity and community structure in the East China Sea by 454 sequencing of the 16S rRNA gene 被引量:8
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作者 董逸 赵苑 +7 位作者 张文燕 李艳 周锋 刘诚刚 吴莹 刘素美 张武昌 肖天 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第3期527-541,共15页
The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater... The 454 sequencing method was used to detect bacterial diversity and community structure in the East China Sea. Overall, 149 067 optimized reads with an average length of 454 nucleotides were obtained from 17 seawater samples and fi ve sediment samples sourced in May 2011. A total of 22 phyla, 34 classes, 74 orders, 146 families, and 333 genera were identifi ed in this study. Some of them were detected for the fi rst time from the East China Sea. The estimated richness and diversity indices were both higher in the sediment samples compared with in the seawater samples. All the samples were divided by their diversity indices into four regions. Similarity analysis showed that the seawater samples could be classifi ed into six groups. The groups differed from each other and had unique community structure characteristics. It was found that different water masses in the sampling areas may have had some infl uence on the bacterial community structure. A canonical correspondence analysis revealed that seawater samples in different areas and at different depths were affected by different environmental parameters. This study will lay the foundation for future research on microbiology in the East China Sea. 展开更多
关键词 细菌多样性 群落结构 中国东海 RRNA基因 测序法 16S 海水样品 多样性指数
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Spatial and temporal variation of particulate organic carbon in the PN section of East China Sea 被引量:5
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作者 ZHU Zhuoy WU Ying +1 位作者 ZHANG Jing WEI Hao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第5期89-99,共11页
Variations of the particulate organic carbon and nitrogen (POC/PN) along the PN section in the East China Sea (ECS) were examined based on POC/PN data obtained in September 2002. A comparison with others work indi... Variations of the particulate organic carbon and nitrogen (POC/PN) along the PN section in the East China Sea (ECS) were examined based on POC/PN data obtained in September 2002. A comparison with others work indicates that POC is the highest in summer, followed by autumn and spring, and the lowest in winter. Generally, POC concentration decreases seawards, and the in situ productivity in September plays an important role in POC distribution. POC in the PN section is composed of terrestrial, resuspended, in situ produced carbon and carbon originated fi'om the Kuroshio waters. The Changjiang River effects the ECS in the PN section, but the influence is mainly minimiged beyond 123.5° E because of barrier effect. The impact of Kuroshio subsurface water (KSSW) over shelf break can also effect POC distribution, with high POC concentration there. 展开更多
关键词 POC PN East China Sea PN section
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Suspended sediment concentration mapping based on the MODIS satellite imagery in the East China inland, estuarine, and coastal waters 被引量:2
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作者 杨宪平 SOKOLETSKY Leonid +1 位作者 魏小岛 沈芳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期39-60,共22页
The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration(SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters.... The purpose of this research is to improve the retrieval accuracy for the suspended sediment concentration(SSC) from in situ and satellite remote sensing measurements in turbid East China estuarine and coastal waters. For this aim, three important tasks are formulated and solved: 1) an estimation of remote-sensing reflectance spectra R_(rs)(λ) after atmospheric correction; 2) an estimation of R_(rs)(λ) from the radiometric signals above the air-water surface; and 3) an estimation of SSC from R_(rs)(λ). Six different models for radiometric R_(rs)(λ) determination and 28 models for SSC versus R_(rs)(λ) are analyzed based on the field observations made in the Changjiang River estuary and its adjacent coastal area. The SSC images based on the above-mentioned analysis are generated for the area. 展开更多
关键词 悬沙浓度 卫星影像 MODIS 华东地区 沿海水域 内陆 映射 河口
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Distribution of Dissolved Inorganic Arsenic and Its Seasonal Variations in the Coastal Area of the East China Sea 被引量:3
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作者 CHENG Yan REN Jingling +2 位作者 LI Dandan LIU Sumei ZHANG Jing 《Journal of Ocean University of China》 SCIE CAS 2006年第3期243-250,共8页
Water samples were collected in the coastal area of the Changjiang Estuary on four cruises from August 2002 to May 2003. The seasonal variations of dissolved inorganic arsenic (DIAs) distributions were analyzed. The r... Water samples were collected in the coastal area of the Changjiang Estuary on four cruises from August 2002 to May 2003. The seasonal variations of dissolved inorganic arsenic (DIAs) distributions were analyzed. The results showed that the distributions of DIAs were mainly influenced by the terrestrial input and the intrusion of the Kuroshio Subsurface Water (KSSW). The concentration of the total dissolved inorganic arsenic (TDIAs) decreased consecutively from winter to summer, while it increased in autumn. The distributions of TDIAs showed some relationships with salinity and suspended particulate matter (SPM). The relationships between DIAs speciation (including arsenite [As(Ⅲ)] and arsenate [As(Ⅴ)]), biological activity and the availabilities of the phosphate were investigated in the study area for the cruise August 2002. The ratio of As (Ⅲ)/TDIAs increased with the decrease of phosphate concentrations. In the bottom water, the As(Ⅲ)/TDIAs ratio decreased with the increasing of N/P. The concentration of TDIAs decreased 28.7% approximately after the occurrence of harmful algal blooms (HAB) because of the uptake of arsenate by algae. Further study is needed about the arsenic source/sink relationships in their vertical or horizontal profiles and the uptake mechanism during the occurrence of harmful algal blooms. 展开更多
关键词 无机砷 溶解性 季节变化 东海 海洋化学
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^(226)Ra and ^(228)Ra tracer study on nutrient transport in east coastal waters of Hainan Island,China 被引量:2
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作者 Ni SU Jin-zhou DU Tao JI, Jing ZHANG 《Water Science and Engineering》 EI CAS 2011年第2期157-169,共13页
Material fluxes (e.g., nutrients) from coastal waters to offshore areas play an important role in controlling the water quality of the adjacent sea areas not only by increasing nutrient concentration hut also by cha... Material fluxes (e.g., nutrients) from coastal waters to offshore areas play an important role in controlling the water quality of the adjacent sea areas not only by increasing nutrient concentration hut also by changing nutrient structures. In this study, naturally occurring isotopes, ^226Ra and ^228Ra, were measured with the alpha spectrometry in the Wenjiao-Wenchang and Wanquan estuaries and adjacent sea areas along the east coast of Hainan Island. The excess ^226Ra and ^228Ra activities were observed by comparison with the values derived from the conservative mixing of freshwater and seawater end-members in both estuaries. Using a one-dimensional diffusion model, the horizontal eddy diffusion coefficient of 3.1 6 × 10^5 cm^2/s, for nutrients diffusing from their sources, was derived from 228Ra activities. Consequently, the corresponding nutrient fluxes flowing into the coastal waters were assessed. The results can provide useful information for the study of the mixing and exchange processes of coastal waters as well as dissoluble pollutant transport in this sea area. 展开更多
关键词 Ra isotope ^226Ra and 228Ra tracers horizontal eddy diffusion coefficient nutrient flux east coastal waters of Hainan Island
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Particulate organic carbon export flux by ^(234)Th/^(238)U disequilibrium in the continental slope of the East China Sea 被引量:1
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作者 BI Qianqian DU Jinzhou +2 位作者 WU Ying ZHOU Jing ZHANG Jing 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第10期67-73,共7页
234Th is widely used to quantify the magnitude of upper ocean particulate organic carbon (POC) export in oceans. In the present work, the rates of particulate organic carbon export were measured based on the distrib... 234Th is widely used to quantify the magnitude of upper ocean particulate organic carbon (POC) export in oceans. In the present work, the rates of particulate organic carbon export were measured based on the distribution patterns of 234Th/238U disequilibrium in the water column within the continental slope of the East China Sea (ECS) during May 2011. The profiles of particulate and dissolved 234Th activities at all three stations showed a relative deficit with respect to 238U in the upper 100 m of the water column. The dissolved 234Th scavenging rates and the particulate 234Th removal rates and their residence times were calculated by a one-dimensional steady state model. The results showed that the dissolved a34Th scavenging rates and the particulate 234Th removal rates ranged from 12.4-61.4 dpm/(m3.d) and from 3.8-21.8 dpm/(m3.d), respectively. The residence times of dissolved and particulate 234Th were in the range of 3.4-158 d and 63.7- 96.5 d, respectively. Combined with the measurement of POC/Z34Th ratios of suspended particles, POC export flux (calculated by carbon) from the euphotic zone was estimated in the study region, which ranged from 4.14-14.7 mmol/(m2 .d), with an average of 8.21 mmol/(m3.d), occupying 35% of the prime productivity in the study area. The results of this study can provide new information for better understanding the carbon biogeochemical cycle within the continental slope of the ECS. 展开更多
关键词 234Th/238U disequilibrium residence time POC export East China Sea (ECS)
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Cross-shore suspended sediment flux in the salt marsh pioneer zone of Chongming eastern beach in the Chang- jiang Estuary in China 被引量:1
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作者 WANG Chu YAO Dongjing +2 位作者 HE Baogen ZHOU Naisheng XU Shiyuan 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2010年第6期62-72,共11页
Between April 2002 and April 2003,in situ measurements of water depth,current velocity and suspended sediment content were carried out in edge region of East Chongming salt marsh and neighboring bald flat in the Chang... Between April 2002 and April 2003,in situ measurements of water depth,current velocity and suspended sediment content were carried out in edge region of East Chongming salt marsh and neighboring bald flat in the Changjiang (Yangtze) Estuary under different weather conditions.Cross-shore suspended sediment flux was calculated and analyzed.The results show that under calm weather conditions,the current velocity process in bald field and salt marsh area varied differently during semidiurnal tidal cycles.Owing to current velocity asymmetry,mean SSC during flood tide phase was 1.8 times higher than that of ebb tide phase.As a result,net onshore sediment flux controlled cross-shore suspended sediment transport process and salt marsh pioneer zone was generally accreting.There was significant positive correlation between total sediment flux and quartic power of maximum water depth.It indicates that tidal ranges dominate suspended sediment transport and sedimentation process in the salt marsh pioneer zone under the calm weather condition.The sedimentation rate on the adjacent mudflat was higher than the salt marsh,which induced stable accreting of salt marsh towards the sea.The wind events enhanced SSC and current velocity during the semidiurnal tides.And the remarkable onshore net sediment flux could occur on the high marsh and mudflat close to the marsh fringe during the short period under the rough weather condition. 展开更多
关键词 current velocity suspended sediment content flux salt marsh eastern beach
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Characterization of longshore currents in southern East China Sea during summer and autumn 被引量:1
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作者 Peng Li Benwei Shi +4 位作者 Yangang Li Sijian Wang Xin Lv Yaping Wang Qing Tian 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2020年第3期1-11,共11页
Current characteristics and vertical variations during summer and autumn in the southern East China Sea were investigated by measuring current profile, tide, wind, and wave data for 90 d from July 28 to October 25, 20... Current characteristics and vertical variations during summer and autumn in the southern East China Sea were investigated by measuring current profile, tide, wind, and wave data for 90 d from July 28 to October 25, 2015. Our results are:(1) The current was mainly a(clockwise) rotating flow, displaying reciprocating flow characteristics,and vertically the current directions were the same throughout the vertical profile.(2) The horizontal current speed was strongest during August(summer) with an average speed of 51.8 cm/s. The average current speeds during spring tides were highest in August and weakest in September, with speeds of 59.9 and 42.8 cm/s,respectively.(3) Considerable differences exist in average current speeds in different layers and seasons. The highest average current speeds were found in the middle–upper layers in August and in the middle–lower layers in September and October.(4) The residual current speed was highest in August, when the speed was 12.5–47.1 cm/s,whereas the vertical average current speed was 34.3 cm/s. The depth-averaged residual current speeds in September and October were only 50% of that in August, and the residual current direction gradually rotated in a counter-clockwise direction from the lower to surface layers.(5) Typhoon waves had a significant influence on the currents, and even affected the middle and lower water layers at depths of >70.0 m. Our results showed that the currents are controlled by the dynamic interplay of the Taiwan Warm Current, incursion of the Kuroshio Current onto the continental shelf, and monsoonal changes. 展开更多
关键词 NORTHEAST TAIWAN ocean current summer and AUTUMN TYPHOON
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Distribution of heavy metals and nutrients in rainwater in coastal regions between the southern Yellow Sea and East China Sea 被引量:1
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作者 刘昌岭 张国森 +1 位作者 任宏波 张经 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2005年第2期230-237,共8页
Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values, concentrations of heavy met... Rainwater samples were collected in series in Qianliyan Island (southern Yellow Sea) and Shengsi Archipelago (East China Sea) between May 2000 and May 2002, chemical analysis for pH values, concentrations of heavy metals (Cu, Pb, Zn and Cd) and nutrients (NH4+, NO3-, PO43-, SiO32-) were performed. Results indicate that concentrations of most of the heavy metals and nutrients in rainwater show clear seasonal variation, i.e. high level in winter and low level in summer. Regionally, concentrations are higher in the southern Yellow Sea than in the East China Sea, but the annual input of heavy metals into oceans by wet deposition is similar in both stations. However, the input of nutrients by wet deposition in the East China Sea is 2–3 times higher than that in the southern Yellow Sea. In individual, Pb and PO43- are input to the sea mainly by dry deposition; whereas Cu, Zn, Cd and N compounds are input dominantly by wet deposition, the N/P ratios in the rainwater from two stations are much higher than those in seawater, showing a significant impact of atmospheric wet deposition on marine production and biogeochemical circulation of nutrients in these sea regions. 展开更多
关键词 黄海南部 中国海东部 重金属 营养元素 海洋化学
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Sources of sediment in tidal flats off Zhejiang coast,southeast China 被引量:1
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作者 Jia JIA Xingze ZHANG +3 位作者 Ruhui ZHOU Michael MEADOWS Dhritiraj SENGUPTA Lidong ZHU 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第4期1245-1255,共11页
The growth of tidal flats off Zhejiang coasts in southwestern China has provided substantial areas for local agriculture and construction activities.To evaluate modern and future development of tidal flats in the regi... The growth of tidal flats off Zhejiang coasts in southwestern China has provided substantial areas for local agriculture and construction activities.To evaluate modern and future development of tidal flats in the region,a good understanding of sediment sources is necessary.Previous research has concluded that the Changjiang(Yangtze)River is the dominant supplier of sediments to this part of the southeast Chinese coast,despite the fact that sediment delivery from this source has been decreased markedly in the past two decades.In this study,we investigated the sources of tidal flat sediments,and the magnetic and geochemical properties of recent tidal flat sediments along the Zhejiang coast were compared with those discharged from rivers.Magnetic and geochemical properties of the tidal flat samples reveal statistically distinct sediment provenance groups.The magnetic and geochemical scatter plots show that the suspended sediment samples are naturally divided into two different groups,one including the Changjiang River and Qiantang River material,and the other including the Jiaojiang,Oujiang,and Feiyun Rivers that located in the central and southern parts of the study areas.At last,a binary source of tidal flat sediments along the Zhejiang coast was determined,with the substantial majority originating from local rivers,while a much smaller proportion emanates from the Changjiang River to the north.We conclude that the sediment contribution of the Changjiang River to tidal flat development in the region has been markedly overestimated,with important implications for management. 展开更多
关键词 tidal flats Zhejiang coastal area magnetic and geochemical characteristics sediment source tracing
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Forest characteristics and population structure of Glyptostrobus pensilis, a globally endangered relict species of southeastern China 被引量:1
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作者 Cindy Q. Tang Yongchuan Yang +14 位作者 Arata Momohara Huan-Chong Wang Hong Truong Luu Shuaifeng Li Kun Song Shenhua Qian Ben LePage Yi-Fei Dong Peng-Bin Han Masahiko Ohsawa Buu Thach Le Huu Dang Tran Minh Tri Dang Ming-Chun Peng Chong-Yun Wang 《Plant Diversity》 SCIE CAS CSCD 2019年第4期237-249,共13页
The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. F... The Chinese water pine Glyptostrobus pensilis is the sole surviving species of the genus Glyptostrobus. It is endemic to southern China, central Vietnam, and eastern Laos, and today it is nearly extinct in the wild. Forest community characteristics and population structure of G. pensilis in China have remained un-known up to now. We investigated six swamp forest stands and analyzed their forest community characteristics (i.e. vertical stratification, species composition, and diversity) and population structure, including the frequency distribution of DBH (diameter at breast height) and age-classes as found in Fujian Province, southeastern China. The vertical stratifications of all the forest stands were rather simple. The remaining wild specimens ranged from roughly 15 to some 357 years for an average of ca. 85 years, with only a few individuals less than 20 years old. Compared with the stands and populations of G. pensilis in Vietnam, the taxonomic compositions of the stands in the two regions were different, except for the dominant species-G. pensilis. The Shannon-Wiener index showed the overstory of each stand had much lower diversity (0.26 on average) in Fujian Province than that (1.97 on average) in Vietnam, whereas the diversity indices were about the same (around 2.41) for the understories in the two regions. Furthermore, we discovered 18 G. pensilis seedlings at the study sites in Fujian Province. This discovery demonstrates that G. pensilis regeneration is extremely poor and its populations are declining, although these populations are rela-tively healthier than those in Vietnam. 展开更多
关键词 Age-class Fujian Province Glyptostrobus Regeneration RELICT plant VIETNAM
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