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九龙江口本中1995年有机物的转移 总被引：1，自引：0，他引：1
１９９５年３个航次调查研究结果表明,九龙江口水体总有机物的含量受悬浮物含量控制。在Ｓ〈５的低盐度区,悬浮泥沙和有机物产生明显的絮凝;在Ｓ〉５的广阔海域,它们的行移接近于理想混合。估算得出九龙江河流的入海一约;悬浮泥沙为９．８＊１０＾５ｔ／ａ;总ＣＯＤ为３．２＊１０＾ｔ／ａ,其中溶解态ＣＯＤ为２．１＊１０＾４ｔ／ａ约占２／３,为水体有机物的主要开矿如换算为溶解有机碳,则ＤＯＣ的平均通量为３．２＊１０ 相似文献
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入海污染物在线监测是实现海洋污染总量控制和测管协同的关键手段之一。本文基于布设在福建省九龙江口的多参数浮标,获取2014?2018年浮标盐度和荧光溶解有机质(FDOM)数据,结合人工采样测定化学需氧量(COD)浓度,建立了河口区COD浓度的快速反演模型。使用有效浓度法外推得到河端COD浓度,结合流量数据估算了高频率的COD入海通量,利用通量分解模型定量分析了COD入海通量的调控因素。结果表明:(1) COD河端有效浓度的拟合值与实测值的偏差为(10.4±8.8)%,模型能够较好地反演九龙江口河端的COD浓度;(2)在季节尺度上,受2015?2016年超强El Ni?o事件影响,2016年旱季的异常降雨降低了河流COD浓度,但是径流量的增加仍然显著提高了该季节COD的入海通量;(3)在年际尺度上,2015?2016年El Ni?o事件所引起的异常降雨事件导致2016年九龙江COD入海通量为(4.4 ± 0.9)×104 t/a,显著高于2014年、2015年及2017年的3.0×104～3.2×104 t/a。上述研究结果表明,FDOM水质浮标在线监测系统,有助于实现对陆源COD入海通量及其调控因素的长期连续高频监测,可为海洋生态环境保护和管理提供重要技术支撑。 相似文献
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从234Th的固/液分配看海洋胶体的作用 总被引：8，自引：2，他引：6
1994—1995年期间,利用β计数法实测了南沙群岛海域、南海东北部海域、厦门湾塔角附近海域和九龙江河口区共计116份海水样品中溶解态与颗粒态234Th的放射性比活度。结果表明,颗粒态234Th占总34Th的份额大小顺序为：九龙江河口区＞厦门海塔角附近海域＞南沙海域。南海东北部海域。234Th的条件分配系数Kd介于1．1×104—20×106dm3／kg之间,平均为2．2×105dm3／kdKd与总悬浮颗粒物含量（7SAN呈负相关关系：lg（Kd）＝－0．59·lg（TSM）＋5．67,这一“颗粒物浓度效应”可归因于海洋胶体物质的存在。由上述关系获得4个研究海区胶体浓度与悬浮颗粒物浓度的函数关系：Cc＝f（TSM0．59）。 相似文献
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渤海COD与石油烃环境容量计算 总被引：7，自引：0，他引：7
总结评述海洋环境容量计算的3类方法,分析了它们的适用条件和不足之处,并对最优化法加以改进计算了渤海的环境容量。然后用HAMSOM模式模拟了渤海的流场,用SPM模式模拟了渤海的浓度场,计算了渤海的COD和石油烃环境容量。渤海在Ⅰ~Ⅳ类海水水质标准下的COD环境容量分别为36.59×104t/a,54.88×104t/a,73.13×104t/a和91.45×104t/a;在Ⅰ~Ⅳ类海水水质标准下的石油烃环境容量分别为2.82×104t/a,16.86×104t/a和28.17×104t/a。 相似文献
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九龙江口生物可利用磷的行为与入海通量 总被引：6，自引：0，他引：6
于1995年3、5月在九龙江口进行两个航次的现场调查,研究不同形态磷的河口行为,并估算生物可利用磷的入海通量。结果表明,在S＜20区域内,溶解活性磷（DRP）的行为受控于“缓冲机制”,其含量在8～10μg／dm3水平上下波动。颗粒磷中MgCl2。可提取磷（MgCl2-P）含量随盐度增大而增大,并与叶绿素a以及悬浮物中Fe、Mn、Al含量呈正相关关系。NaOH／NaCl可提取磷（NaOH／NaCl－P）随盐度增大按指数关系下降,其含量与悬浮物中Fe、Mn、Al含量呈正相关关系。HCl可提取磷（HCl－P）在河口区的行为表现为保守混合。九龙江口生物可利用磷入海通量约517t／a,其中潜在生物可利用磷（PBAP）的贡献为溶解活性磷（DRP）的3倍。 相似文献
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137Cs示踪法研究太湖流域土壤侵蚀分布与总量 总被引：3，自引：0，他引：3
利用137Cs示踪法研究了太湖流域不同地貌和土地利用类型的土壤侵蚀速率分布,初步估算了太湖流域的土壤侵蚀总量。结果表明,土地利用类型相同时,丘陵山坡中点的土壤侵蚀速率与整个坡面的平均值相近;太湖流域山坡中上部以自然坡地为主,土壤侵蚀速率仅为186.6t/km2.a;山坡下部以茶园种植为主,土壤侵蚀速率为3898.5t/km2.a。平原区水田的侵蚀速率与其到山脚的距离正相关,随距离的增大由堆积转变为侵蚀并逐渐增大,山脚水田堆积量和湖岸水田侵蚀量分别为2585.9和6325.7t/km2.a,平均侵蚀速率约为1869.9t/km2.a。太湖流域土壤侵蚀总量约为3446.7×104t,流域土壤侵蚀导致的输入太湖的泥沙量年均约为34.5×104t,与实际监测结果基本一致,说明土壤侵蚀是太湖泥沙输入的主要来源。本研究结果初步证明了利用137Cs示踪法研究太湖流域土壤侵蚀与湖泊沉积通量定量关系的可行性。 相似文献
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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
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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
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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
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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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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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《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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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
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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
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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
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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