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1.
青岛近海碱度的研究及其测定方法的比较 总被引：1，自引：0，他引：1
2012年春季以青岛近海为研究海域,采用pH单点法、自动电位滴定法及溶解无机碳(DIC)计算法测得海水总碱度(Alk),并对这3种方法进行比较;探讨该海域海水Alk的分布特征及影响因素;对过滤前后样品的Alk差值与叶绿素(Chl-a)间的相关性进行分析。结果表明:DIC计算法和pH单点法得出的Alk误差较大,电位滴定法测定的Alk结果精密度较高;青岛近海海域表层水体中Alk范围为2 070~2 364μmol/kg,其平均值2 310μmol/kg;过滤前后样品的Alk差值与Chl-a含量具有一定的相关性,表明浮游植物和颗粒物对Alk有影响。 相似文献
2.
《热带海洋学报》2016,(2)
于2014年分4个季度对大亚湾4个典型功能区(人工鱼礁区、水产养殖区、核电站温排区和石化排污区)以及湾口区表层海水的温度、盐度、p H、总碱度(TA)等进行了调查,比较分析了不同区域表层水体溶解无机碳(DIC)体系的组成和分布特征,估算了海?气界面CO2的交换通量(FCO2),并对FCO2的主要影响因素进行了分析。结果显示,调查海域表层水体的DIC、HCO3–、CO32–浓度和CO2分压pCO2年变化范围分别为1248.8~1841.9μmol·kg–1(1624.8?143.1μmol·kg–1)、1069.2~1615.7μmol·kg–1(1382.5?126.1μmol·kg–1)、152.7~283.5μmol·kg–1(236.2?35.4μmol·kg–1)、11.4~44.9Pa(21.2?7.4Pa);各区域间的DIC、HCO3–、CO32–和pCO2无显著差异(P0.05)。表层海水FCO2的年变化范围为–37.3~4.5mmol·(m2·d)–1[–22.4?9.8mmol·(m2·d)–1],各区域FCO2(按正负数值大小)的季节变化呈现夏季秋季春季冬季的特征,且夏季显著高于其他季节(P0.05);在全年尺度上,各区域的FCO2均为负值,表现为大气CO2的汇,碳汇强度呈现湾口区鱼礁区排污区温排区养殖区的特征,而各区域间无显著差异(P0.05)。偏回归分析显示,大亚湾湾口区和养殖区的FCO2时空分布主要受盐度影响,在鱼礁区和温排区主要受温度的影响,而在排污区则主要受海水p H的影响。 相似文献
3.
基于2013年9月底至10月初在印尼爪哇岛南部海域调查得到的碳酸盐参数和相关水文数据,首次报道了该海域pH的分布,并重点探讨了南爪哇上升流(季风上升流)对其影响。结果显示上升流影响区表层pH低于周围非上升流影响区。通过两端元混合模型,定量讨论了上升流的物理输运和生物活动对pH的影响。研究表明,上升流的物理输运至少造成了海表层盐度增加0.4个单位,溶解无机碳(DIC)增加110μmol/kg,pH降低约0.2个单位;同时,在上升流区,强烈的生物活动(叶绿素a浓度大于0.4mg/m3)使得DIC的降低量达70μmol/kg,pH的增加量达0.15个单位。总体来看,该研究区域的物理输运作用大于生物作用,综合效应表现为DIC的增加和pH的降低。另外,同上升流的物理输运作用和生物作用相比,上升流引起的表层冷却和增盐对pH的影响较小(热力学作用)。 相似文献
4.
5.
胶州湾毗邻青岛市区,是受人类活动影响显著的海湾。开展胶州湾水-气界面CO2通量研究,有助于厘清受人类活动严重干扰下的边缘海(湾)CO2源汇的控制机制。根据2013年4月在胶州湾走航连续观测所得pCO2数据,结合水文、化学和生物等要素的同步观测资料及以往本课题组获取的冬季2、3月份航次数据,对胶州湾海域pCO2分布及影响因素进行了分析探讨。结果表明:表层海水pCO2测得值在392~1 648μatm之间,平均值为496μatm。4月份胶州湾水体垂直混合均匀,且水柱对表层碳酸盐体系的影响显著。4月份胶州湾浮游生物初级生产弱于2、3月份,而生物的好氧呼吸作用要强于2、3月份。因此,生物好氧呼吸作用的增强是4月份胶州湾表现为大气CO2源的主要原因,同时温度升高也是导致胶州湾冬季到春季表层pCO2升高的重要因素,其影响程度仅次于生物好氧呼吸作用。总体来说,4月份胶州湾表现为大气CO2的源,水-气界面CO2交换通量在-8.22~490.68mmol·m-2·d-1之间,平均值为17.34mmol·m-2·d-1。 相似文献
6.
夏季黄海海水碳酸盐体系特征 总被引：1，自引：0，他引：1
根据2016年7月对黄海海域碳酸盐体系参数pH和总碱度(A_T)开展的调查,结合温度、盐度、营养盐及叶绿素等同步观测数据,分析了夏季黄海海水碳酸盐体系的特征并讨论了其控制机制。结果表明,碳酸盐体系特征在不同水团间差异很大。表层与底层pH分别在7.915~8.307和7.849~8.074之间,高值位于长江冲淡水和黄海沿岸流中。表层与底层A_T分别为2063~2358μmol/kg和2205~2372μmol/kg,总体表现为由南往北递增。长江冲淡水A_T较低,黄海沿岸流A_T较高。海水总溶解无机碳(C_T)在黄海北部山东半岛附近含量较高,底层明显高于表层。表层海水二氧化碳分压(pCO_2)与表层C_T变化趋势相似。霰石饱和度(?_(Ar))在底层较低,最低值仅为1.28。Pearson相关分析结果显示,水团中A_T与盐度的相关性较大(R0.7),pH与营养盐的相关性较大。说明碳酸盐体系特征主要受水团混合和生物活动的影响。水团混合是影响A_T分布的主导因素。表层营养盐浓度过低导致浮游植物生长受限,受限区域pH变化不大,底层再矿化过程释放大量CO_2导致底层pH降低。 相似文献
7.
青岛近海冬末春初海水碳酸盐体系的特征 总被引：1，自引：0，他引：1
通过在青岛近岸海域采集海水样品,测定了海水pH、总碱度(TA)、溶解无机碳(DIC)以及溶解钙离子,并根据这些参数计算了海水中的碳酸氢根、碳酸根等分量以及海水二氧化碳分压(pCO_2)、碳酸钙饱和度等参数。各站点海水pH范围为8.09~8.18,平均8.13;TA范围为2309~2345(mol/kg,平均2325(mol/kg;DIC范围为2158~2200(mol/kg,平均2180(mol/kg;海水中溶解钙离子的浓度为0.3700~0.3732g/kg,平均0.3716g/kg。求得海水pCO_2范围为371~476(atm,平均415(atm;方解石和文石的饱和度范围分别为2.31~2.84和1.45~1.78,平均值分别为2.57和1.61。通过与温度、盐度进行比较,发现冬末春初青岛近岸海域海水总碱度、溶解无机碳和溶解钙离子具有较为均匀的特征,是冬季混合导致的结果。海水pH有一定的变化性,与营养盐和叶绿素a的关系显示,观测区西部已开始增强的生物生产使海水pH升高,pH是该季节影响海水pCO_2、碳酸钙饱和度等参数的主要因素。该季节青岛近海总体上表现为大气CO_2的弱源,但西部海区是大气CO_2的弱汇。 相似文献
8.
胶州湾秋季表层海水pCO_2分布及水-气界面通量 总被引：1，自引：0，他引：1
根据2007年11月31日在胶州湾走航连续观测所得pCO2数据,结合水文、化学和生物等要素的同步观测资料,对胶州湾海域pCO2分布及其影响因素进行了探讨。结果表明:秋季胶州湾表层海水pCO2实测值在315~720μatm之间,平均值为423μatm。东部海域由于有机物降解及李村河水输入的影响表现为大气CO2的源;西部海域由于浮游植物活动的影响为大气CO2的弱汇区;湾中部水交换较好的海域,浮游植物活动和有机物降解共同影响着pCO2的分布。总体来说,秋季胶州湾表现为大气CO2的弱源,海-气界面CO2交换速率在-5.94~23.15 mmol.m-2.d-1之间,平均值为2.87 mmol.m-2.d-1,由此可估算出秋季胶州湾可向大气释放940.74 tC。 相似文献
9.
海水碳酸盐体系参数是反映碳循环调控机理和季节性酸化过程的重要海水化学参数.本文根据2011年3月、7月、11月和12月4个不同季节航次获取的长江口海域海水碳酸盐体系参数,探讨了长江口-东海P断面溶解无机碳(DIC)和总碱度(T A)的空间分布特征及其影响因素.结果表明:内陆架区,DIC和T A的平均值均表现为:夏季<秋季<冬季<春季;垂直分布上,夏季和秋季受长江冲淡水影响出现层化现象,春季和冬季均垂直混合较均匀.东海内陆架DIC与温度和DO呈显著负相关;T A则受温度和DO变化影响较小,与盐度呈正相关.结合2011年东海外陆架的PN断面数据分析,DIC和pH分别与表观耗氧量(AOU)呈显著正相关和负相关,东海外陆架的pH/AOU的斜率为-0.0027 pH/(μmol·kg-1);而内陆架区的pH/AOU的斜率为-0.0018 pH/(μmol·kg-1),低于黑潮次表层水中pH/AOU的斜率.东海内陆架区由于存在季节性的通风作用以及较强的海水碳酸盐体系缓冲能力,底层水体中因有机质耗氧降解导致的季节性酸化信号在一定程度上得到了缓解. 相似文献
10.
基于2012年7月对东海的调查,剖析了其水体中各形态碳(pCO2、DIC、DOC、POC)的区域分布特征,估算了海-气界面CO2的交换通量(FCO2),探讨了影响其交换的主要因素,在此基础上,结合历史资料初步分析了近十几年来该海域海-气界面CO2交换通量的变化趋势。结果表明,2012年7月长江口邻近海域相对南部陆架区具有较低的DIC浓度,而DOC与POC的浓度相对较高。调查区域表层水pCO2变化范围为96.28~577.7μatm(1atm为101 325Pa),平均值为297.6μatm,低值区出现在长江冲淡水区(30°~33°N,123°~125°E),高值区主要分布在东海陆架的南部区域。表层水pCO2主要受控于长江冲淡水的输入和混合(盐度)、台湾暖流以及生物生产等。调查海域2012年7月海-气FCO2平均为(-6.410±7.486)mmol/(m2·d),表现东海在夏季是大气CO2的汇区,区域碳汇强度由强到弱依次为:长江冲淡水区(CDW)、黄东海混合水区(YEMW)、陆架咸淡水混合区(SMW)、近岸上升流区(CUW)和台湾暖流区(TWCW),东海夏季每日吸收大气CO2(以C计)约(18.3±19.8)kt。结合历史资料分析发现,近十几年来东海夏季碳汇强度有增强趋势,CDW区的海-气界面CO2通量平均年增速为-0.814mmol/(m2·d),即海水吸收大气二氧化碳每年增加约54.6kt,是夏季东海碳汇增加的最主要贡献者。 相似文献
11.
Arne Schnack-Friedrichsen Angela M. Davis Jim D. Bennell Dei G. Huws 《Marine Georesources & Geotechnology》2001,19(4):221-243
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.
Shigehisa Nakamura 《Marine Geodesy》2000,23(1):55-61
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
13.
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
14.
Coastal inundation associated with extreme sea levels is the main factor which leads to the loss of life and property whenever a severe tropical cyclonic storm hits the Indian coasts. The Andhra and Orissa coasts are most vulnerable for coastal inundation due to extreme rise in sea levels associated with tropical cyclones. Loss of life may be minimized if extreme sea levels and associated coastal flooding is predicted well in advance. Keeping this in view, location specific coastal inundation models are developed and applied for the Andhra and Orissa coasts of India. Several numerical experiments are carried out using the data of past severe cyclones that struck these regions. The simulated inland inundation distances are found to be in general agreement with the reported flooding. 相似文献
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16.
《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
17.
Hoi-Soo Jung Kap-Sik Jeong Yong-Shik Chu Sung-Hyun Park Ki-Hyune Kim 《Marine Georesources & Geotechnology》2001,19(3):181-195
Grain size and water content in box-core sediments from the Clarion-Clipperton fracture zone (C-C zone) in the northeast equatorial Pacific were analyzed in detail to understand the downcore variations across a hiatus between Quaternary and Tertiary layers. Grain-size distributions in the topmost core sediments show two modes: a coarse mode (peaked at 50 μm) and a fine mode (at 2-25 μm). The coarse mode disappears gradually with depth accompanied by the dissolution of siliceous fossil tests, whereas the fine mode coarsens due to the formation of authigenic minerals. Water content increases abruptly across a color boundary between an upper pale brown layer and a lower dark brown layer that is the hiatus between Quaternary and Tertiary layers. Abundant smectites and microvoid molds, which are created by the prolonged fossil dissolution in the underlying sediment, are attributed for the abrupt downcore variation of water content. Overall variations in grain size and water content in the topmost core sediments in the western C-C zone are possibly constrained by the dissolution of biogenic siliceous fossils. Variations in geotechnical properties related to these changes must be considered in the design of nodule collectors. 相似文献
18.
Shigehisa Nakamura 《Marine Geodesy》2001,24(1):27-33
This article concerns an interrelation between the sea levels and the western boundary flow near a tectonic boundary in a local zone in the Northwestern Pacific. In this zone, sea level variations at stations located on the coast facing the Pacific are studied to find the interrelation between variations of the Kurosio flow as an index of the distance of the flow axis off a specific coast. The result is discussed after data processing of the monthly means of the sea levels, and a notice is taken of variations caused by active crustal upheavals during a seismic event, a local earthquake. 相似文献
19.
This study tests the hypothesis that the in situ void ratio of surficial marine sediments may be predicted from shear wave velocity-depth data with a reliability equal to that of other methods currently available. Shear wave velocity is fundamentally controlled by the number of grain-to-grain contacts per unit volume of material and by the effective stress across those contacts. In this study, three previously established empirical formulae are used to predict void ratio from velocity-depth data. Field data were acquired along a transect off the northern Californian coast across which water depth increased from 35 to 70 m and seafloor sediment type varied from sand to silty-sand, respectively. A towed seafloor sled device was used to collect shear wave refraction data, and a marked, systematic decrease in velocity was observed along the line, ranging from 35-70 m/s for the coarse, near-shore material to 25-40 m/s for the finer, offshore deposits. Void ratios predicted from these velocities were compared with data measured directly from box-core samples. Of the formulae used for prediction, two agree remarkably well with the control data. Both predicted and control values increase from 0.6-0.8 for the sandy material to 1.1-1.5 for the silty-sand. Thus, this study does not disprove the hypothesis set and demonstrates the potential of field shear wave velocity-depth data as a means of delineating spatial variation in void ratio for surficial marine sediments in a remote, nondestructive manner. 相似文献
20.
Particulate samples were collected from the Changjiang river system during a flood period, in May 1997, and POC, stable isotope and lipids associated with particles were examined. Results showed the decrease (0.84% ～ 1.88%) of organic carbon content from the upper reaches to the estuary.δ13C values of particulate organic carbon was in the range of -24.9×10-3 to -26.6×10-3, which were close to the isotopic signature of continental C3 vegetation. Total particulate n-alkanes concentrations varied from 1.4 to 10.1μg/dm3,or from 23.7 to 107μg/g of total suspended matter. Fatty acids were present in all the samples, from 1.4 to 5.4μg/dm3, with saturated and unsaturated straight-chain and branched compounds in the carbon number range from C12 to C30. Both δ13C and the ratio of carbon content to nitrogen content indicate the predominance of terrestrial inputs (soil organic matter) among the particles. The biomarker approach has been used to identify the relative portion of terrigenous and autochthonous fraction in the particulate samples. The distribution of fatty acids suggests a striking phytoplanktonic and microbial signal in most particle samples. The terrestrial alkanes are used to estimate the contribution of terrestrial inputs along the mainstream. 相似文献