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1.
南日岛海域溶解态Cu、Pb、Cd含量及其与营养盐的关系   总被引:3,自引:0,他引:3  
高淑英  邹栋梁 《台湾海峡》1995,14(2):195-198
本文首次报道了福建南日岛海域溶解态Cu、PB、Cd的含量,探讨了它们与营养盐的关系。1990年5月溶解态Cu、Pb、Cd的平均含量分别为0.84、0.230、0.023μg/dm3;1990年10月分别为0. 78、0.290、0. 033μg/dm3。其5月溶解态Cu与无机氮N(NO3-+NO2-+NH4 )线性回归的相关式为Cu(μg/dm3)=-0. 789+0.328N(μmol/dm3),相关系数r=0.853,原子比△Cu:△N=5.17×10-3:1。  相似文献   

2.
研究了离子色谱-电感耦合等离子体质谱(IC-ICPMS)联用技术直接进样测定海水中IO3^-和I^-的方法.采用IonPacAG23离子色谱保护柱分离IO3^-和I^-,以浓度4.0mmol/dm3的KOH为流动相,流量为1.0cm3/min,每个样品的分析时间为2.5min.采用2.5×10^-3cm^3的进样量,IO3^-和I^-的检出限分别达到0.6和0.4nmol/dm2,可满足海水中碘形态的定量分析.该方法的IO3^-和I^-浓度范围在2.0nmol/dm3~2.0μmol/dm3.  相似文献   

3.
硒对钝顶螺旋藻生长的影响及其在细胞中的累积和分布   总被引:6,自引:0,他引:6  
本文研究了硒对纯顶螺旋藻(Spirulinaplatensis)生长的影响及其在细胞生化组成中的分布。结果表明,当硒浓度低于50mg/dm3时,对钝顶螺旋藻生长的抑制作用不明显,在低浓度下(<10mg/dm3)可促进其生长;当硒浓度超过50mg/dm3时则起抑制作用,高浓度对藻体起毒害作用。藻细胞中总硒含量与培养液中的硒浓度有关,在0~40mg/dm3范围内,硒含量随着培养液中硒浓度的增加而增加:从0mg/dm3的2.50×10-5(m/m,dw)到40mg/dm3的231.45×10-6(m/m,dw),至50mg/dm3,又开始降低为174.26×10-6(m/m,dw);硒在S.platensis生化组成中的分布,以蛋白质含量为最高,可达总硒的49.22%~71.49%,而脂类及碳水化合物-氨基酸中的含量则较低,分别为总硒含量的3.59%~6.18%和1.45%~2.56%,硒在各组成中的含量与培养液中的硒浓度有关,其变化趋势与总硒含量的一致。  相似文献   

4.
厦门西港浮游植物吸收磷酸盐的粒级特征   总被引:4,自引:0,他引:4  
厦门西港微型浮游植物(3~20μm)吸收磷酸盐的百分比、吸收速率常数和单位体积吸收速率均最大,分别为74.85%、8.28×10-5/s和5.38×10-5μmol/(dm3·s),小型浮游植物(20~200μm)次之,超微型浮游植物(0.2~3μm)最小;单位叶绿素a的吸收速率是超微型浮游植物最大[5.38×10-5μmol/(μg·s)],微型次之,小型最小。相关分析表明各粒级浮游植物吸收磷酸盐的百分比与相应粒级浮游植物的叶绿素a含量和光合速率的百分比呈良好的正相关关系。  相似文献   

5.
本文基于日本东京湾、伊势湾和浜名湖的调查资料,详细地比较了这3个海湾海水中的溶存甲烷浓度、饱和度。表层海水中,溶存甲烷浓度以供名湖最高,达95nmol/dm3,伊势湾和东京湾相近,分别为41nmol/dm3和37nmol/dm3;其表层测定浓度是其平衡浓度的13~78倍,并分别计算了这3个海湾中甲烷的海气交换通量;用平均值外推法得出全球海洋环境中总的甲烷海气交换通量为6.3Tg/a。  相似文献   

6.
利用切向超滤技术对九龙江口天然水体中胶体相(1 kDa~0. 45μm)、真溶解相(1 kDa)和"溶解相"(0. 45μm)的溶解有机碳和无机氮进行了分离与提取,初步探讨了水环境因子对其理化特性的影响机制,进而探讨了它们的来源和转化.结果表明,切向超滤过程的膜空白和质量平衡符合技术要求;溶解有机碳、亚硝酸盐氮、氨氮、硝酸盐氮和无机氮存在形式以真溶液相(1 kDa)为主,其在胶体相中的质量浓度分别为0. 207~0. 810 mg/dm3、0. 001~1. 870μg/dm3、ND~2. 08μg/dm3、0. 62~79. 30μg/dm3和1. 07~81. 10μg/dm3;胶体态溶解有机碳(COC)含量主要受陆源输入控制.  相似文献   

7.
羟基自由基对细胞的三大基本分子核酸、蛋白质、葡萄糖有着强烈破坏作用。压载水中羟基的比值浓度达到0.63mg/L时,含有微生物液体中的总蛋白质含量从1.49g/100mL降到0.993g/100mL,减少了33.4%;核酸中RNA、DNA的含量分别从2.43μg/mg、0.96μg/mg分别减少到1.29μg/mg、0.19μg/mg,分别减少46.9%、80.2%;葡萄糖含量从0.246mg/100mL增加到0.492mg/100mL,增加了1倍。试验数据表明,羟基自由基氧化、分解、破坏了微生物细胞三大基本分子核酸、蛋白质、葡萄糖,这是微生物致死的主要生化原因之一。  相似文献   

8.
利用Delft3D数学模型建立了平潭综合实验区近岸海域物质输运数学模型,模拟了澳前、海坛海峡北、海坛海峡南、流水、竹屿5个排污口在不同污水排放量下COD、无机氮浓度的分布.结果表明:在污水排放规模为3.0×10^4t/d时,竹屿排污口邻近海域海水COD、无机氮质量浓度分别为3.80、0.51mg/dm3,流水排污口邻近海域海水COD、无机氮质量浓度分别为3.60、0.42mg/dm3,都超过二类海水水质标准值,表明这2个海域水动力条件较弱、污染物扩散缓慢,不是理想的排污口.在污水排放量为1.5×10^5t/d时,海坛海峡北排污口邻近海域海水COD、无机氮质量浓度分别为1.87、0.28mg/dm3,海坛海峡南排污口邻近海域海水COD、无机氮质量浓度分别为1.84、0.27mg/dm3;澳前排污口在污水排放量为5.0×10^5t/d时,其邻近海域海水COD、无机氮质量浓度分别为2.48、0.28mg/dm3,均符合二类海水水质要求,表明上述海域水动力条件良好、纳污能力强、环境容量大,是较好的污水排放口.该研究可为平潭综合实验区海域污水排放口选址优化提供科学依据,为该海域入海污染物总量控制和海洋环境管理提供参考.  相似文献   

9.
报道了杂色鲍碱性磷酸酶(ALP)在甲醇、乙醇、丙醇、甲醛、丙酮等溶液中的失 活动力学.结果表明:酶的剩余活力随着有机溶剂浓度的增大而迅速下降.测得上述 5种有机溶剂对该酶的半抑制率(IC50)分别为5.41、3.07、1.80、31.0×10-3、2.30 mol/dm3.在这些有机溶剂溶液中酶的失活过程都是可逆反应.检测醇、醛、酮对该酶 的失活作用机理,结果表明甲醇、乙醇、丙醇对杂色鲍ALP的失活作用均为非竞争性 机制,其抑制常数分别为5.36、3.02、1.80mol/dm3.甲醛、丙酮对杂色鲍ALP的失活 作用都呈现为混合型抑制,其对游离酶的抑制常数(K1)分别为24.7×10-3、1.66 mol/dm3;对酶-底物络合物的抑制常数(KIS)分别为56.2×10-3、5.40mol/dm3.  相似文献   

10.
海洋生物样品中硒的氢化物发生-原子荧光分析(HG-AFS)   总被引:2,自引:0,他引:2  
采用硼氢化钠还原法将试样中硒还原为挥发性硒化氢 ,氩为载气将硒化氢吹出并导入火焰原子化器进行原子荧光测定。以正交设计法对该还原反应、氢化物转移、原子化及原子荧光测定条件等进行了详细研究。实验结果表明 ,在佳化条件下 ,该法检出限为 0 .0 72μ g/ dm3,相对标准偏差为 2 .0 %。标准曲线表明 ,在 0 .0 0 0~ 1.0 0 0μ g/ dm3Se浓度范围内 ,有理想的线性关系。本法测定海洋生物样品硒的回收率为 95.8%~ 10 2 .4 %。  相似文献   

11.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

12.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

13.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

14.
The effect of different fixation and storage protocols on the flow cytometric (FCM) simultaneous analysis of bacterioplankton and phytoplankton in coastal seawater samples (Mediterranean coastal lagoons) was investigated. FCM measurements (cell number, fluorescence and scatter characteristics) were obtained through DAPI staining. Three fixatives [glutaraldehyde (GA), formaldehyde (FA) and paraformaldehyde (PFA)] and two storage (3 months duration) methods (5 °C and −196 °C) were tested. Two dominant populations were detected in studied samples: bacteria and eukaryotic picophytoplankton. Adding fixatives (2% final concentration) appears necessary to obtain FCM exhaustive counts of all the bacteria and phytoplanktonic cells. This was related to the permeation effect of fixatives which allowed a better DAPI staining of the cells. Maximum fluorescence, i.e. optimal staining of the cells was obtained with FA or PFA, and significant lower fluorescences with GA. Fixed samples stored at 5 °C induced rapid cell loss. Only storage in liquid nitrogen of samples fixed with FA or PFA, allows mid-term (≥4 months) preservation of bacteria or picophytoplankton cell numbers, and limited evolution of DAPI-induced fluorescence and scatter characteristics.  相似文献   

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《海洋学报(英文版)》2014,(9):F0003-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

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19.
A set of 27 marine planktonic bacteria isolated from the polar regions was characterized by 16S rDNA sequencing and physiological and biochemical testing. More than half of these bacteria were positive for caseinase, gelatinase and 13-glucosidase, and could utilize glucose, maltose or malic acid as carbon source for cell growth. Twelve isolates expressed nitrate reduction activities. Except for one antarctic isolate BSwlO175 belonging to Actinobacteria phylum, these isolates were classified as γ-Proteobacteria, suggesting that γ-Proteobacteria dominated in cultivable marine bacterioplankton at both poles. Genus Pseudoalteromonas was the predominant group in the Chukchi Sea and the Bering Sea, and genus ShewaneUa dominated in cultivable bacterioplankton in the Prydz Bay. With sequence similarities above 97%, genus Psychrobacter was found at both poles. These 27 isolates were psychrotolerant, and significant 16S rDNA sequence similarities were found not only between arctic and antarctic marine bacteria ( 〉 99% ), but also between polar marine bacteria and bacteria from other aquatic environments ( ≥ 98.8% ), including temperate ocean, deep sea, pond and lake, suggesting that in the polar oceans less temperature-sensitive bacteria may be cosmopolitan and have a bipolar, even global, distribution at the species level.  相似文献   

20.
The relationship between the flux of exotic benthic foraminiferal tests (i.e. tests which are supplied from open-sea sources alone) in a tidal inlet and that of bulk sediment was analysed, which can be expressed as two first-order linear equations. According to this relationship, in order to determine net sediment transport directions in the entrance, the test concentration in surficial sediments of the tidal basin can be compared against a ‘ critical level ’. The critical level is determined for the conditions that no net transport of bulk sediment is present within the entrance. If the observed concentration (averaged over the tidal basin) is higher than the simulated critical level, then the net sediment transport is directed to landward. This method is applied to the analysis of net sand transport at Christchurch Harbour, a tidal inlet system located in southern England. In this investigation, concentrations of exotic foraminiferal tests in the surficial sediments of the tidal basin and ebb tidal delta area were obtained from the analysis of sea-bed sediment samples. A series of probable critical levels were calculated based upon the data sets with regard to: (1) sediment discharge from the rivers; (2) magnitude of sediment discharge within the entrance during the ebb; (3) the test concentration outside the harbour; (4) the thickness of the moving layer; and (5) two parameters associated with dispersive processes. The results show that the concentration in the tidal basin sediment is higher than a number of simulated critical concentrations for representative cases. Consequently, the high level of the concentration of exotic benthic foraminiferal tests within the harbour should be explained as a result of landward net transport of sands within the entrance.  相似文献   

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