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关于征海补偿问题的探讨 被引量:5
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作者 李正骥 贾冰凌 《国土资源》 2002年第10期32-33,共2页
近几年随着经济的发展,一些海滨城市现有港口吨位不足,需要兴建或扩建码头.因此,在工程前期都遇到同一个问题:"征海".
关键词 海域补偿费 安置补助费 补偿方式 土地补偿费 海域使用权 征海补偿
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渔业水域滩涂征收征用与相关称谓解析
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作者 赵万忠 《海洋开发与管理》 2008年第3期88-90,共3页
近年来,渔业水域滩涂征收征用过程中侵害渔民利益的事件时有发生,由此也引发一系列社会问题。学者们在对该领域研究过程中使用了不同的称谓。本文从制度构建的层面,运用比较分析的方法对各种称谓进行辨析,并指出:渔业水域滩涂既有征收,... 近年来,渔业水域滩涂征收征用过程中侵害渔民利益的事件时有发生,由此也引发一系列社会问题。学者们在对该领域研究过程中使用了不同的称谓。本文从制度构建的层面,运用比较分析的方法对各种称谓进行辨析,并指出:渔业水域滩涂既有征收,也可能存在征用;渔业水域滩涂征收征用主要关注的是征收征用的条件和补偿,失海失涂则主要关注的是保障和救济;征海、占用等则属于模糊性用语。 展开更多
关键词 渔业水域滩涂征收征用 失海失涂 征海 占用 制度构建
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浅析海西港口建设中渔民失海问题 被引量:2
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作者 林超阳 《消费导刊》 2010年第5期223-223,225,共2页
海西港口建设规模宠大,发展迅速,其征海速度永远超过了经济发展水平和周期,因而在短时间内消化民生就业和社会养老保障问题的难度骤然增大。本文就海西港口建设中渔民因失海所面临的补偿机制、民生就业和社会保障问题作出初步探讨。
关键词 失海渔民 征海补偿 社会保障 就业
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Analysis on the Hydrochemical Characteristics of Groundwater and the Formation Reason in Wadi Bay Area of Libya
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作者 宋晓明 高翠萍 +1 位作者 Basher HM 杨悦锁 《Agricultural Science & Technology》 CAS 2010年第11期28-32,118,共6页
[Objective] The research aimed to analyze the formation reason of groundwater hydrochemical characteristics in the dry valley area of Wadi Bay of Libya and provide the scientific basis for the reasonable development u... [Objective] The research aimed to analyze the formation reason of groundwater hydrochemical characteristics in the dry valley area of Wadi Bay of Libya and provide the scientific basis for the reasonable development utilization and the environmental protection of groundwater.[Method] Took Wadi Bay area(dry valley)of Libya as the example,Piper trilinear graphic representation method,the descriptive statistics,the ion ratio coefficient method and the isotope evidence were used to systematically study the special hydrochemical characteristics of shallow groundwater in the arid climate condition in Wadi Bay area of Libya.[Result] The salt content of groundwater in the area was very high,and TDS was during 3.2-8.4 g/L.The main groundwater type was Cl·SO4-Na·Ca,then was Cl·SO4-Na·Ca·Mg.The concentrations of Cl-,Na+ and SO2-4,etc.in the groundwater in 70 km from the sea had the remarkable variation,but the concentrations of Mn2+,Ba2+,Si2+,NH+4 and NO-3 didn't have the same variation phenomenon.[Conclusion] The hydrochemical characteristics of shallow groundwater didn't relate to the dissolution infiltration reaction,the evaporation concentration effect and human activities.The major cause was the mixing effect of salt and fresh water in the invasion process of seawater. 展开更多
关键词 Hydrochemical characteristics of groundwater Seawater invasion Libya Arid area Wadi Bay
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海上风电场联合送出优化方案研究 被引量:3
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作者 常胜 李炬添 +2 位作者 张振 沈云 王海龙 《南方能源建设》 2019年第2期49-53,共5页
[目的]结合我国广东地区海上风电场布置及典型送出方案,对两个300MW风电场联合送出的方案进行了探讨。[方法]在电气主接线、海缆选型、可靠性分析、海缆敷设与供货、可比投资等方面进行了分析比较。[结果]最终得出联合风场送出的优化方... [目的]结合我国广东地区海上风电场布置及典型送出方案,对两个300MW风电场联合送出的方案进行了探讨。[方法]在电气主接线、海缆选型、可靠性分析、海缆敷设与供货、可比投资等方面进行了分析比较。[结果]最终得出联合风场送出的优化方案,即设2座220kV海上升压站+1座陆上集控中心,其中1座升压站通过1回3×1000mm^2海缆接至另1座升压站GIS,汇流后再通过2回3×1000mm^2海缆一并送出至陆上集控中心。[结论]联合送出的优化方案可大大节省投资并减少用海面积,可为后续海上风电场电气设计提供参考。 展开更多
关键词 海上风电场 联合送出 征海 载流量
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Distribution characteristic and variation trend of planktonic dinoflagellate in the Taiwan Strait from 2006 to 2007 被引量:3
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作者 林更铭 杨清良 +1 位作者 林维含 王雨 《Marine Science Bulletin》 2012年第1期68-79,共12页
Based on 4 cruise surveys from July 2006 to October 2007 in the Taiwan Strait, the species composition, community structure and spatio-temporal distribution of dinoflagellate were studied. A total of 131 dinoflagellat... Based on 4 cruise surveys from July 2006 to October 2007 in the Taiwan Strait, the species composition, community structure and spatio-temporal distribution of dinoflagellate were studied. A total of 131 dinoflagellates belonging to 18 genera were identified. The population was dominated by hyperthermal and hyperhaline species accounting for 72.52% of the total species. Eurythermal and euryhaline species were the second most common one accounting for 25.19% of the total species. It was only 2.29% for neritic species. The maximum species number occurred in summer, while the maximum cell density appeared in spring. The average dinoflagellate cell density was 404.96x104 cells/m3. It showed that the dinof]agellate cell density increased from the nearshore waters to the open sea and from the north to the south. Compared with the results during 1984-1985, the horizontal distribution pattern and seaeonal variation of the dinofiagellate have not changed significantly, but the dinoflagellate cell density increased by 3.01 times. Further analysis of the dinoflagellate abundance variations both in the spatial and temporal aspects, indicated that the abundance of dinoflagellate increased more significantly in cold seasons, and there was a larger increase in the north of the Taiwan Strait. Besides, the dinoflagellate community structure changed notably. It showed that the diversity and evenness index were relatively high, and the proportion of dinoflageliate cell density to the total phytoplankton increased. 展开更多
关键词 planktonic dinoflagellate distribution characteristics variation trendTaiwan Strait
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Wave statistics for ship seakeeping in China offshore 被引量:1
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作者 刘首华 牟林 +3 位作者 王兴 陈长霖 岳心阳 高志刚 《Marine Science Bulletin》 CAS 2014年第2期1-12,共12页
Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptab... Ocean waves are the core environmental elements affecting the movements and structure design of ships. Statistical analysis of wave parameters is the basis for the establishment of long-term ship environmental adaptability prediction model. The observations from coastal stations, buoys, altimeters and volunteer ships that cover from 1993 to 2011 were interpolated into miller Ion-lat grids by using bilinear method and the analytical fields of ocean waves were given. By using optimal interpolation, the analysis wave fields were assimilated into the WAVEWATCH III (WW3) simulation results. From the assimilated results, the wave rose statistics, the wave height of muitiyear return period and the extreme 2-D wave spectrum are related to the ship seakeeping were calculated. Finally, the wave statistics in China offshore were analyzed in detail. 展开更多
关键词 ocean waves statistical characteristics ship seakeeping shipenvironmental adaptability
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Numerical Study on Tides in the Taiwan Strait and its Adjacent Areas 被引量:3
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作者 朱佳 胡建宇 +4 位作者 张文舟 曾淦宁 陈德文 陈金泉 商少平 《Marine Science Bulletin》 CAS 2009年第2期23-36,共14页
Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan S... Diurnal and semi-diurnal tides in the Taiwan Strait and its adjacent areas are calculated by using a two-dimensional finite-difference model. Compared with data of more than 20 observation stations around the Taiwan Strait, the model-produced results agree quite well with those of previous researches using observational data from coastal tidal gauge stations. According to the results, the co-tidal and co-range charts are given. Furthermore, the characteristics of 8 major tidal constituents have been uminated respectively. The result shows that: (1) The tide motion can be attributed to the interaction between the degenerative rotary tidal system in the north and the progressive tidal system in the south. (2) The southward and northward tidal waves of semi-diurnal tide converge in the middle of the Taiwan Strait while the diurnal tidal waves propagate southwestward through the Taiwan Strait and the Luzon Strait. (3) The maximum amplitude of semi-diurnal tides exists at the area between the Meizhou Bay and Xinghua Bay, and that of diurnal tides appears in the region to the east of the Leizhou Peninsula, (4) The patterns of co-tidal and co-range charts of N2, K2 and P1, Q1 tidal constituents are similar to those of M2, S2 and K1 O1 tidat constituents, respectively 展开更多
关键词 Taiwan Strait and its adjacent areas tidal characteristics MODEL
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Distribution of heavy metals in suspension in Bohai Bay 被引量:1
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作者 董玉波 《Marine Science Bulletin》 CAS 2016年第1期93-95,共3页
Selecting suspension sample 51 stations in Bohai Bay contents of heavy metals(Fe, Mn, Si, Ba) analysis, studied the distribution of the suspension of heavy metals. It Showed that in the study area, the content of iron... Selecting suspension sample 51 stations in Bohai Bay contents of heavy metals(Fe, Mn, Si, Ba) analysis, studied the distribution of the suspension of heavy metals. It Showed that in the study area, the content of iron was the highest, silicon content was lowest; in descending order: Fe>Mn>Ba>Si; the coefficient of variation is between 7.60 and 110.35; except barium greater the degree of dispersion(coefficient of variation is greater than 100).With the samples of stations, the 4 kinds of heavy metals are from low to high, from the south to the north. Silicon content was the highest in 51 stations. The other 3 elements appeared in 50 stations. 展开更多
关键词 Bohai Sea heavy metals DISTRIBUTION
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Island instantaneous coastline extraction based on the characteristics of regional statistics of multispectral remote sensing image
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作者 王丰 刘书明 +3 位作者 卢文虎 杜琼玮 姜伟男 刘金 《Marine Science Bulletin》 CAS 2014年第1期25-37,共13页
This study adopted IKONOS remote sensing images and selected spectral characteristic areas, through regional pixel statistics and calculating weight coefficients of each band, processed the images with the spectral no... This study adopted IKONOS remote sensing images and selected spectral characteristic areas, through regional pixel statistics and calculating weight coefficients of each band, processed the images with the spectral normalized method, which made the features of islands, land and water features more obviously in the images. On this basis, the OTUS was used to determine the optimal segmentation threshold, and the normalization image binarization was made, thus the island coastline was extracted. This method used the characteristic curve method to separate the land and water, obtained the binarization images and maintained the original edge effectively. The coastline that was extracted by Binary Morphology was continuous, reliable and high signal-to-noise ratio. The results showed that this method could extract the coastline fast, simply and effectively, which had the practical value. 展开更多
关键词 coastline extraction ISLANDS spectral characteristics of regional statisticsBinary Morphology IKONOS
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Physico-Chemical Properties and Laboratory Hyperspectral Reflectance of Coastal Saline Soil in Shangyu City of Zhejiang Province, China 被引量:12
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作者 SHI ZHOU, HUANG MINGXIANG and LI YANInstitute of Agricultural Remote Sensing and Information System, Zhejiang University, Hangzhou 310029 (China) 《Pedosphere》 SCIE CAS CSCD 2003年第3期193-198,共6页
45 and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984respectively, in Shangyu of Zhejiang Province,... 45 and 50 composite soil samples were collected, respectively, from twoagricultural fields, that were enclosed and reclaimed from coastal tidal-flat areas in 1996 and 1984respectively, in Shangyu of Zhejiang Province, China, to investigate the physico-chemicalproperties and the hyperspectral characteristics of the saline soils and to make an assessment ontheir relationships. The reflectance spectra of saline soils were measured using a spectroradiometerin laboratory. The mean spectral curves of the saline soils from the two sites different inreclamation year showed that the saline soil taken from the recently reclaimed land with highersalinity demonstrated a lower reflectance intensity in the spectral region from about 550 nm to 2300nm. In addition, nine absorption bands, i.e., 488 nm, 530 nm, 670 nm, 880 nm, 940 nm, 1400 nm, 1900nm, 2 200 nm and 2 300 nm, were chosen as the spectral bands to investigate the relationshipsbetween soil physico-chemical properties by means of Pearson correlation analysis. Finally, thefirst two principal components were calculated from nine absorption bands and used to discriminatethe saline soil samples taken from two sampled fields. The results indicate that it is feasible todetect physico-chemical properties of saline soils from fields reclaimed for varying time periods onthe basis of the hyperspectral data. 展开更多
关键词 COAST HYPERSPECTRAL RECLAMATION saline soils
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Purification and characterization of novel κ-carrageenase from marine Tamlana sp.HC4 被引量:4
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作者 孙飞雪 马悦欣 +1 位作者 王颖 刘倩 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第6期1139-1145,共7页
We isolated a bacterial strain (HC4) that is able to degrade k-carrageenan from a live specimen of the red alga Hyalosiphonia caespitosa. With 16S rRNA gene sequencing, we identified the strain as Tamlana sp., and t... We isolated a bacterial strain (HC4) that is able to degrade k-carrageenan from a live specimen of the red alga Hyalosiphonia caespitosa. With 16S rRNA gene sequencing, we identified the strain as Tamlana sp., and then purified an extracellular K-carrageenase from a culture of Tamlana sp. HC4 by ammonium sulfate precipitation, Sephadex G-200 gel filtration chromatography, and DE-cellulose 52 anion-exchange chromatography. The purified enzyme yields a single band on SDS-PAGE with a molecular mass of 66.4 kDa. The optimal pH and temperature for κ-carrageenase activity are at 8.0 and 30~C, respectively. The enzyme is stable over the range ofpH 7.2-8.6 below 45℃. The enzyme activity is strongly inhibited by Zn2+ and Cu2+ at 1 mmol/L. The enzyme-catalyzed reaction follows Michaelis-Menten kinetics with the Michaelis constant (Kin) at 7.63 mg/ml. Analysis of the degradation products of the κ-carrageenase by ESI-MS and 13C-NMR spectroscopy indicates that the enzyme degrades κ-carrageenan down to the level ofκ-neocarrabiose sulfate. 展开更多
关键词 κ-carrageenase Tamlana PURIFICATION CHARACTERIZATION
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Topographic features around Zhongshan Station,southeast of Prydz Bay 被引量:2
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作者 冯守珍 薛佐 迟万清 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2008年第4期469-474,共6页
Considering the complex topographic features of the southeast of Prydz Bay where China's Zhongshan Station is located,three types of geomorphologic units can be identified,i.e., submarine slopes,canyons,and terrai... Considering the complex topographic features of the southeast of Prydz Bay where China's Zhongshan Station is located,three types of geomorphologic units can be identified,i.e., submarine slopes,canyons,and terrains.The major topographic features in the study area are the submarine canyon and trough system outside the calving ice front of Dalk Glacier.A 3.8 km×80 m fissure is found on the submarine terrain at Zhongshan Anchorage,which,once triggered by geological hazards such as earthquakes and ice falls,would be a threat to the usage and maintenance of the anchorage. 展开更多
关键词 Prydz Bay Zhongshan Station Zhongshan Anchorage topography feature
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Morphological Studies on the Infraciliature of a Planktonic Ciliate,Tintinnopsis brasiliensis(Ciliophora:Tintinina) 被引量:1
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作者 CAI Shengfang SONG Weibo +1 位作者 XU Dapeng CHIANG Kuoping 《Journal of Ocean University of China》 SCIE CAS 2006年第1期55-57,共3页
A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid & Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation afte... A poorly-described marine planktonic ciliate, Tintinnopsis brasiliensis Kofoid & Campbell, 1929, collected from the Taiping Cape of Qingdao, China, was morphologically investigated based on permanent preparation after protargol impregnation and was compared with other related congeners. According to the infraciliature, three ciliary groups can be recognized, which reveals a very stable structure among specimens and denotes that the pattern of infraciliature is, apart from the features of the lorica, a highly reliable criterion for species identification. 展开更多
关键词 INFRACILIATURE Tintinnina CILIOPHORA Tintinnopsis brasiliensis
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Analysis of Dynamic Characteristics of the 21st Century Maritime Silk Road 被引量:1
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作者 ZHANG Xudong ZHANG Jie +3 位作者 FAN Chenqing MENG Junmin WANG Jing WAN Yong 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第3期487-497,共11页
The 21st century Maritime Silk Road(MSR) proposed by China strongly promotes the maritime industry. In this paper, we use wind and ocean wave datasets from 1979 to 2014 to analyze the spatial and temporal distribution... The 21st century Maritime Silk Road(MSR) proposed by China strongly promotes the maritime industry. In this paper, we use wind and ocean wave datasets from 1979 to 2014 to analyze the spatial and temporal distributions of the wind speed, significant wave height(SWH), mean wave direction(MWD), and mean wave period(MWP) in the MSR. The analysis results indicate that the Luzon Strait and Gulf of Aden have the most obvious seasonal variations and that the central Indian Ocean is relatively stable. We analyzed the distributions of the maximum wind speed and SWH in the MSR over this 36-year period. The results show that the distribution of the monthly average frequency for SWH exceeds 4 m(huge waves) and that of the corresponding wind speed exceeds 13.9 ms^(-1)(high wind speed). The occurrence frequencies of huge waves and high winds in regions east of the Gulf of Aden are as high as 56% and 80%, respectively. We also assessed the wave and wind energies in different seasons. Based on our analyses, we propose a risk factor(RF) for determining navigation safety levels, based on the wind speed and SWH. We determine the spatial and temporal RF distributions for different seasons and analyze the corresponding impact on four major sea routes. Finally, we determine the spatial distribution of tropical cyclones from 2000 to 2015 and analyze the corresponding impact on the four sea routes. The analysis of the dynamic characteristics of the MSR provides references for ship navigation as well as ocean engineering. 展开更多
关键词 Maritime Silk Road risk factor ocean wave wind speed tropical cyclone
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Measuring Spatio-temporal Characteristics of City Expansion and Its Driving Forces in Shanghai from 1990 to 2015 被引量:4
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作者 TIAN Li LI Yongfu +1 位作者 SHAO Lei ZHANG Yue 《Chinese Geographical Science》 SCIE CSCD 2017年第6期875-890,共16页
Urbanization has both direct and indirect impacts on land use change, and analyzing spatio-temporal characteristics of land use change is essential for understanding these impacts. By comparing Landsat TM images, this... Urbanization has both direct and indirect impacts on land use change, and analyzing spatio-temporal characteristics of land use change is essential for understanding these impacts. By comparing Landsat TM images, this paper examines the changes of land use structure and landscape patterns in Shanghai from 1990 to 2015. It finds that the city doubled in size, with the growth of isolated construction land being most significant among eight land use types. A land use change matrix was established and landscape indices were selected to evaluate the change of spatial structure in Shanghai. In order to identify the main driving forces of city expansion in Shanghai, this research ran partial least square regression models to assess the impact of 10 social-economic factors on land use change of Shanghai from 1990 to 2015. It then conducted bivariate correlation analysis to explore the drivers of change of various land use types: urban settlement, rural settlement and isolated construction land. Besides quantitative analysis, this paper analyzes the influence of policy-dimensional factors in land use change. It concludes with future potential research topics on land use change in a rapidly urbanizing context. 展开更多
关键词 URBANIZATION land use change partial least squares regression driving forces SHANGHAI
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Analysis of the distribution characteristics of ^(226)Ra and ^(228)Ra and their sources in the western part of Qinghai Lake 被引量:3
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作者 孔凡翠 沙占江 +5 位作者 杜金洲 苏维刚 于晨光 赵顺利 胡菊芳 冶梅 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第6期1402-1412,共11页
The ^226Ra and ^228Ra activities of Qinghai Lake surface water, groundwater, river water, suspended particles, and bottom sediments were measured in a gamma-ray spectrometer. The sources of ^226Ra and ^228Ra were disc... The ^226Ra and ^228Ra activities of Qinghai Lake surface water, groundwater, river water, suspended particles, and bottom sediments were measured in a gamma-ray spectrometer. The sources of ^226Ra and ^228Ra were discussed according to their distribution characteristics. ^226Ra and ^228Ra activities (dpm/(100 L)) ranged from 14.13±0.22 to 19.22±0.42 and 17.724-0.66 to 30.96:kl.47 in the surface water of the North Bay, respectively, and from 7.88±0.24 to 33.80±0.47 and 15.73±0.74 to 57.31±1.44, respectively, in the South Bay. The surface water near the estuary had a lower salinity and had a higher concentration of radium isotopes than the samples collected further away. The farther offshore the sample, the higher the salinity was, and the lower the radium isotope activity. The distribution of radium activities in the western part of Qinghai Lake is controlled by several factors, including Buha River runoff, desorption from suspended particles derived from the river, groundwater discharge, and a small amount of diffusion from the sediment. 展开更多
关键词 ^226RA ^228Ra surface water of Qinghai lake groundwater river water Qinghai Lake
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Vertical structure and evolution of the Luzon Warm Eddy 被引量:7
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作者 陈更新 侯一筠 +1 位作者 储小青 齐鹏 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期955-961,共7页
Eddies are frequently observed in the northeastern South China Sea (SCS). However, there have been few studies on vertical structure and temporal-spatial evolution of these eddies. We analyzed the seasonal Luzon War... Eddies are frequently observed in the northeastern South China Sea (SCS). However, there have been few studies on vertical structure and temporal-spatial evolution of these eddies. We analyzed the seasonal Luzon Warm Eddy (LWE) based on Argo float data and the merged data products of satellite altimeters of Topex/Poseidon, Jason-1 and European Research Satellites. The analysis shows that the LWE extends vertically to more than 500 m water depth, with a higher temperature anomaly of 5℃ and lower salinity anomaly of 0.5 near the thermocline. The current speeds of the LWE are stronger in its uppermost 200 m, with a maximum speed of 0.6 m/s. Sometimes the LWE incorporates mixed waters from the Kuroshio Current and the SCS, and thus has higher thermohaline characteristics than local marine waters. Time series of eddy kinematic parameters show that the radii and shape of the LWE vary during propagation, and its eddy kinetic energy follows a normal distribution. In addition, we used the empirical orthogonal function (EOF) here to analyze seasonal characteristics of the LWE. The results suggest that the LWE generally forms in July, intensifies in August and September, separates from the coast of Luzon in October and propagates westward, and weakens in December and disappears in February. The LWE's westward migration is approximately along 19°N latitude from northwest of Luzon to southeast of Hainan, with a mean speed of 6.6 cm/s. 展开更多
关键词 Luzon Warm Eddy ALTIMETRY ARGO South China Sea
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Seasonal Suspended Particles Distribution Patterns in Western South Yellow Sea Based on Acoustic Doppler Current Profiler Observation 被引量:1
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作者 LI Jianchao LI Guangxue +5 位作者 XU Jishang QIAO Lulu DONG Ping DING Dong LIU Shidong SUN Pingkuo 《Journal of Ocean University of China》 SCIE CAS 2015年第3期385-398,共14页
An Acoustic Doppler Current Profiler (ADCP) observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters (SPM) distribution pattern. The SPM concentra... An Acoustic Doppler Current Profiler (ADCP) observation site was set up in the Western South Yellow Sea from 2012 to 2013 to study the local suspended particle matters (SPM) distribution pattern. The SPM concentration could be semi-quantitatively represented by backscatter intensity (Sv), converted by the echo intensity (E/) of ADCP. Results show two types of SPM in the water column: the quasi-biological SPM and quasi-mineral SPM. The quasi-biological SPM mainly exists in summer half year and is con- centrated above the thermocline. It has periodically diurnal variations with high concentration at night and low concentration in the daytime. The quasi-mineral SPM is located in lower part of the water column, with similar relation to monthly tidal current variation all year round. However, the daily quasi-mineral SPM distribution patterns vary between summer and winter half year. The sunlight is thought to be the origin factor leading to the diurnally vertical motion of the biological features, which might cause the diurnal Sv variation. Unlike in winter half year when tidal current is relatively single driving force of the monthly SPM pattern, the high speed current near the thermocline is also responsible for the concentration of quasi-mineral SPM in summer half year. The sediment input difference between summer and winter half year contribute to the varied daily variation of quasi-mineral SPM with re-suspended SPM ir~ winter and sediments from Yellow Sea Mud Area (YSMA) in summer. The seasonal variations in hydrodynamics, water structure and heavy-wind incidents are the primary factors influencing the differential seasonal SPM distribution patterns. 展开更多
关键词 the South Yellow Sea backscatter intensity suspended particle matters seasonal distribution patterns diurnal periodicvariation
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Effects of photoperiod on daily activity rhythm of juvenile sea cucumber, Apostichopus japonicus (Selenka) 被引量:8
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作者 董贯仓 董双林 +1 位作者 田相利 王芳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1015-1022,共8页
In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a popul... In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects .4.japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments (light:dark (LD) cycles at 0:24, 3:21, 6:18, 9:15, 12:12, 15:9, 18:6, 21:3, and 24:0 under 500Ix) to 60 individuals (29.73±0.23 g) per treatment (with 3 replicates). The enviroramental conditions were set as: water temperature = 16.9±0.3℃, dissolved oxygen〉6.0 rag/L, ammonia〈0.3 mg/L, pH=7.8-8.2, and salinity=30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus (viz. the animals emerged and fed at night and sheltered during the day) were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate (DR) of the animals emerging at "daytime" increased with lengthening "light time" (except for the LD 3:21 cycle). We also found that there was no significant difference in mean DR per day under LD cycles of 6:18, 9:15, 15:9, and 12:12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0:24 and 3:21, and significantly higher than for those under LD cycles of 18:6, 21:3 and 24:0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus. 展开更多
关键词 Apostichopusjaponicus daily behavior PHOTOPERIOD
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