Synoptic variability of currents in the coastal waters of Sochi

We performed investigations of synoptic variability of bottom and surface currents, the flow rate of the Mzymta River, and the wind speed measured with high resolution (10 min periodicity) in the coastal zone of the city of Sochi in May 2009, 2010, 2011, and 2012. Based on the measurements, a Fourier spectral analysis and harmonic analysis were carried out for both low-frequency and high-frequency components of the variability of the current velocities and wind speed. The analysis revealed a similarity of the structures of the main oscillation periods for the currents in the low-frequency spectrum and significant fluctuation periods for the currents in the high-frequency range. In addition, we studied the internal waves generated by the river plume.     

Bedload sediment transport in coastal waters

Formulae for bedload transport of sediments in conditions characteristic of coastal waters are developed from principles of physics. They cover driving forces of: current alone, current plus symmetrical waves, current plus asymmetrical waves, asymmetrical waves alone, and integrated longshore transport. In each case the transport is given as one or more analytical functions of the basic input variables. The formulae are tested against laboratory and field data, and give predictions that lie within a factor of 2 of the measured values for between 47% and 91% of the data, depending on the driving force. The formulae are suited to practical application in coastal waters, especially for transport of coarse materials such as shingle, and also for the bedload component of transport of sand.     

连云港近岸海域沉积物运移趋势

基于连云港近岸海域夏冬季大面积多站表层沉积物样品的粒度分析结果,采用Gisedtrend粒径趋势分析方法,研究了沉积物的运移趋势,探讨了粒径趋势分析的影响因素,结果表明,连云港近岸海域沉积物运移趋势较显著,在海州湾海域沉积物运移趋势为西南向,表现为湾顶淤积;在港口南部海域沉积物运移趋势显示为汇聚区。特征距离、采样网格、周围环境和粒度组分影响粒径趋势的分析结果;综合考虑岸线、岛屿、人工边界等自然环境以及多源粒度组分能够提高粒径趋势分析结果的合理性。     

Tidal currents in the coastal waters east of Hainan Island in winter

Using the 25-h continuing hydrographic observations at three successive stations in February 2012 and the mooring time series of current observations from January to March 2015, the tidal currents and tidal energy fluxes in the coastal waters east of Hainan Island in the northwestern South China Sea were analyzed. The diurnal and semidiurnal(using K 1 and M 2 as proxies, respectively) tidal currents and associated isopycnal undulations were derived with harmonic analysis. Results show that the v...     

利用被动示踪物模拟对黑潮入侵南海的数值研究

由于缺少观测数据和对黑潮水准确定义,很难识别出从太平洋入侵到南海的黑潮水团。本文基于一个经过观测验证的三维模式MITgcm,利用被动示踪物标记黑潮水,研究了入侵南海的黑潮水的时空变化。研究表明,在冬季,黑潮水入侵的范围最广,几乎占据了18°N-23°N和114°E-121°E的区域;并有一个分支进入台湾海峡;黑潮入侵的范围随深度增加逐渐减小。在夏季,黑潮水被限制在118°E以东,且没有分支进入台湾海峡;入侵的范围从海面到约205米是增大的,之后随深度增加逐渐减小。通过分析从2003年到2012年黑潮入侵的年际变化,与厄尔尼诺年和正常年相比,冬季黑潮入侵后向台湾海峡的分支在拉尼娜年是最弱的,这可能与中国大陆东南方向的风应力旋度有关。通过吕宋海峡的黑潮入侵通量（KIT）是西向的,其年平均值约为-3.86×10⁶ m³/s,大于吕宋海峡通量（LST,约-3.15×10⁶ m³/s）。250米以上的KIT约占了全深度通量的60-80%。此外,从2003年到2012年KIT与Niño 3.4指数的相关系数到达0.41,小于LST与Niño 3.4指数的相关系数0.78。     

厦门市近岸海域水环境污染现状及对策研究

厦门市位于中国东南沿海,台湾海峡西岸,具有重要的战略地位。然而随着经济社会的发展,近岸海域水环境污染已成为影响厦门市环境质量的瓶颈。文章在分析近岸海域水质状况的基础上,阐述了厦门近岸海域主要污染物来源及污染的主要原因,并提出了关于提高厦门近岸海域水环境质量的对策建议。     

Assimilation of surface currents into a regionalmodel over Qingdao coastal waters of China

Surface currents measured by high frequency （HF） radar arrays are assimilated into a regional ocean model over Qingdao coastal waters based on Kalman filter method. A series of numerical experiments are per- formed to evaluate the performance of the data assimilation schemes. In order to optimize the analysis pro- cedure in the traditional ensemble Kalman filter （ENKF）, a different analysis scheme called quasiensemble Kaman filter （QENKF） is proposed. The comparisons between the ENKF and the QENKF suggest that both them can improve the simulated error and the spatial structure. The estimations of the background error covariance （BEC） are also assessed by comparing three different methods： Monte Carlo method; Canadian quick covariance （CQC） method and data uncertainty engine （DUE） method. A significant reduction of the root-mean-square （RMS） errors between model results and the observations shows that the CQC method is able to better reproduce the error statistics for this coastal ocean model and the corresponding external forcing. In addition, the sensibility of the data assimilation system to the ensemble size is also analyzed by means of different scales of the ensemble size used in the experiments. It is found that given the balance of the computational cost and the forecasting accuracy, the ensemble size of 50 will be an appropriate choice in the Qingdao coastal waters.     

深圳沿岸海域贝类重金属和贝类毒素污染状况分析

通过检测深圳沿岸海域7种贝类的重金属、麻痹性贝毒(PSP)和腹泻性贝毒(DSP)含量,了解其食用安全性.严格按照国家标准进行检测,采用SPSS 20.0对数据进行Kruskal-Wallis H检验和方差分析.结果表明:各种重金属和贝类毒素在样品中均有检出,汞污染状况良好;铜含量范围为0.52~109.65 mg/kg,超标率为13.67%;铅含量范围为0.01~3.60 mg/kg,超标率为68.35%;镉含量范围为0.015~7.807 mg/kg,超标率为53.96%.PSP和DSP检出率为100%,PSP含量范围为0.30~34.23 ug/100 g;DSP含量范围为1.88~38.41 ug/100 g.总体看来,样品铅、镉超标严重,不同种类贝类重金属含量具有差异且贝类毒素检出率较高,应引起有关部门的重视,加强该海域监测工作.     

Submesoscale variability of the current and wind fields in the coastal region of Sochi

The results of direct high temporal resolution (10 min) measurements of the surface and bottom currents and wind stress in the coastal zone of Sochi in May 2009 are presented. An analysis of the mesoscale and submesoscale variability of the current velocity and wind stress is performed on the basis of these measurements, and their correlation is studied. The principal high-frequency and low-frequency components of the current velocity variability are identified. In the majority of the observation cases, the coastal currents reveal no significant correlation with the mean wind over the studied region. However, the correlations between the currents and the spatial variability of wind are explained well by the local topography.     

Patterns of summer vertical and horizontal currents in coastal waters of the northern Gulf of Aqaba, Red Sea

This study was focused on analysis of the horizontal and vertical current components with correspondence to tide variation, heat flux, seiches and relative backscatter intensity in coastal waters of the northern Gulf of Aqaba during the summers of 2001–2004. Spectrum analysis has shown eight distinguishable peaks of the tide measurements. In addition to semidiurnal and diurnal barotropic tides, signal periods of 8.13, 5.89–6.32 and 4.06 h were related to shallow water compound and overtides of the principal solar and lunar constituent and to seiches (second and third mode) generated in the Red Sea, whereas seiches of the first mode might enhance the semidiurnal tide signal. The shortest periods of 1.02–1.05, 0.50 and 0.36 h were related to seiches (first, second and third mode, respectively) generated in the Gulf of Aqaba. The spectrum analysis and cross-correlation tests of the horizontal and vertical current components and relative backscatter intensity suggested that the vertical motion at the diurnal period was either due to migration of zooplankton or to water convection. Both of which were of the same order as vertical motion induced by horizontal motions of water particles projected parallel on the bottom gradient line. On the other hand, semidiurnal and diurnal periods detected in the vertical currents were caused by the strong signal in the cross-shore current component, first mode seiches generated from the Red Sea and tide. This could be considered as an indicator of the dominant force influencing the currents, such as winds, thermocline depth, seiches and tidal forcing. A permanent convection during summer is likely to occur in the shallow coastal waters due to relatively high inclined bottom, high evaporation and blowing of dry air, as well as the observed dominance of the downward vertical currents in coastal waters.     

河口海岸二维悬沙数学模型挟沙力公式修正及应用

在河口海岸二维悬沙数学模型中,半潮或全潮平均的潮流挟沙能力并不能完全反映其逐时的实际情况,为此进行了分析研究。研究结果表明:1)应用半潮或全潮平均的潮流挟沙力公式进行悬沙数值模拟时,应引入一个修正系数;2)该修正系数与公式中的指数成反比,与相对水深成正比,且与相位角也存在一定联系;3)该修正系数理论正确、实用方便、验证成果良好,实例计算表明能够较好地复演天然悬沙场分布。     

Big squid in big currents

A link is proposed between the processes that led to the evolution of large species of squid and the highly variable, cyclic recruitment seen in squid fisheries. Maximum growth requires maximal feeding and minimal routine metabolism at optimum temperatures, which decrease as squid grow. Topographically induced upwelling zones, inshore of western boundary currents, provide productive environments with appropriate temperatures for all life stages. Most squid are small and live in the tropics or subtropics; locomotor constraints prevent them from swimming long distances. Long annual migrations to spawn upstream in current systems require short-lived squids to maximize rates of growth. Therefore, such systems provide the opportunity and a powerful selective advantage for large size and rapid growth. Increased fecundity and cannibalism provide additional directional selection for large individuals. Current systems show food production peaks (blooms); paralarval release must match these to increase survival. Because squid are semelparous, disruption of delicately balanced lifecycles by physical events can virtually annihilate stocks. Recovery probably requires that populations of large squid "re-evolve" from smaller, more-stable tropical populations of small squid. This recovery phase may extend the "down-side" of abundance cycles. Studies of squid/current systems have focused on western boundary currents, but the Illex complex also associates with eastern boundaries. Such populations are generally smaller than in larger systems, supporting the hypothesis, but more detailed comparisons are required.     

Microbial communities in the coastal surface waters of Zolotoi Rog Bay under the conditions of strong anthropogenic pollution

Using the example of Zolotoi Rog Bay, which is strongly affected by anthropogenic pollution, it was shown that organic pollution essentially influences the structure of the microbial community, causing changes not only in the quantitative but also in the qualitative parameters such as the morphology, the type of metabolism, and the physiological activity of the microorganisms. We noted a zonation in the development and distribution of bacterioplankton, including the heterotrophic microflora in Zolotoi Rog Bay, which is caused by the high density of bacteria at the sites of organic matter supply and their low density in other areas examined, which are less influenced by the sewage. Special ecotrophic groups of microorganisms that are capable of utilizing the organic substratum entering the environment due to the anthropogenic impact become dominating in the heterotrophic microbial biocoenoses.     

福建海区的潮汐和潮流

本文根据实测资料和潮汐学基本理论,分析了福建海区潮波结构和特征、潮汐和潮流主要特征值的分布规律。结果表明,泉州湾以北海区潮汐很强,为半日潮;港湾区因受地形影响潮流很强,性质为半日潮;外海区潮流很弱,性质多为混合潮。福建南部海区潮汐很弱,性质多数是混合潮;潮流很强,性质为半日潮。     

珠江口沿岸水域表层沉积物中重金属含量分布及污染评价

于2009年对珠江口沿岸水域28个采样站位9种重金属元素的含量与分布进行了研究.使用原子吸收分光光度计分别测定了各采样站位沉积物中的Cu、Fe、Zn、Mn、Ni、Pb、Co、Cr和Cd的含量,并使用标准物作了质量控制.采用多种评价方法对不同环境重金属污染水平及潜在生态风险进行了评价.结果显示,珠江口沿岸水域表层沉积物中Cu、Fe、Zn、Mn、Ni、Pb、Co、Cr和Cd的平均含量分别为17.81 ～681.11、22 993.58 ～49 378.76、37.22 ～ 286.07、491.57 ～1 699.63、18.35 ～ 57.72、9.81 ～86.55、11.45 ～41.53、0.65 ～21.22、0.15 ～ 1.77 μg/g(干重).采用海洋沉积物质量标准法结合单因子污染指数法(Pi)评价显示,该海域已受到Cu和Cd污染,其含量均超海洋沉积物一类标准值.结合单元素生态危害因子(E(ri))和多元素潜在生态风险指数(RI)的评价显示,Cd和Cu已达到“重”和“严重”危害等级,其潜在生态风险属于“中度”等级.地质累积指数法(Igeo)评价则显示,Cu和Cd分别属“严重”和“中度”污染程度.综合评价表明,珠江口沿岸水域沉积物受Cu和Cd污染较严重,已对海洋环境和沿岸海水养殖造成严重的潜在危害.建议控制养殖区养殖密度,减少网箱数量和人类养殖活动.     

Distribution and their pollution assessment of heavy metals in the sediments of the Yalu River Estuary and its adjacent coastal waters

The present paper deals with the distribution patterns of heavy metals and the associated influencing factors in the Yalu River Estuary and its adjacent coastal waters.Based upon the analysis of the surficial and core sediments measurements,the pollution of heavy metal and potential ecological risk were evaluated.The burial flux and contents of heavy metals(except for copper) have been continuously increasing since the 1920s.Therefore,the gross potential ecological risk for the sedi-ments was high or very high,and the study area was endangered by heavy metals contamination.Heavy metals originated mainly from upstream pollutant input,correlation analysis showed that chromium,nickel,zinc,cadmium,lead,arsenic,and mercury in the sediments of the middle and west channels as well as the sea area of the western Yalu River Estuary concentrations were most probably derived from similar sources.In contrast,the metal of copper most probably originated from sources different from the other metals.Preliminary studies indicate that copper contamination was most likely the result of emission from mining activities situated at the upstream of the river.The contents of heavy metals in the sediments of estuarine turbidity maximum zone of Yalu River were larger than those of any other areas in the middle channel.With large portion of fine sediments,weaker hydrodynamics,and richer sources of heavy metals,the sediments of the west channel,were even more enriched with heavy metals than those of the middle channel.     

Manganese recycling in coastal waters

Both water and suspended particulate matter in the deep water of the Gulf of St. Lawrence are greatly enriched in manganese. Maximum dissolved manganese concentrations are encountered close to the sediment-water interface whereas the particulate matter with highest manganese content occurs 30–100 m above the bottom. The elevated concentrations are attributed to the diagenetic release of dissolved manganese from the underlying fine-grained sediments and its subsequent precipitation in the water column. The rate of manganese precipitation is rapid compared to the rates of diffusion and mixing in the bottom water. Part of the manganese-enriched particulate matter becomes mixed throughout the water column by advection and diffusion. Thus, particles enriched in manganese can ultimately be carried into the open ocean by prevailing currents. This process, which appears to be widespread in eastern Canadian coastal waters, enables manganese originally associated with rapidly settling terrigenous particles to be transferred to slowly settling fine-grained suspended particles entering the ocean from coastal environments. In this way, riverborne manganese of terrigenous origin may well account for a major proportion of the excess manganese in pelagic sediments.     

Fluorometric in situ measurements of water currents and mingling of waters in cases of heavy turbidity as in coastal shoal areas

By means of the in situ pulse-light fluorometer Variosens the fluorescent substance uranin was used to detect small water bodies. In mixture with a big river (Elbe) a quantity of 40-g uranin only was sufficient for tracer activities during 2 h and was a factor of about 50 above basic noise. It has been found that uranin in turbid water is highly superior to all kinds of rhodamine.     

Oil pollution in the Izu Islands waters

The oil pollution in the Izu Islands waters are observed as follows:

1. Globules and lumps of oil were collected 2.56 g on the average in wet weight by each taw(174 m³) of a larval net at 389 stations, up to the maximum collection of more than 500 g.
2. On the investigation of the Oshima—Torishima line (J1–J10), globules and lumps of oil were collected more at the south of the Kuroshio Current than at the north.
3. In the coastal region (T1–T19) of Japan, many globules and lumps of oil were collected when a cold water mass was located at the west side of the Izu Islands, from south to east side of where the Kuroshio Current took a roundabout and closed near to the Bōsō peninsula (Aug. 1971, Jun. 1972, Aug. 1972), or when the Kuroshio Current took a roundabout the cold water mass which extended as far as Oshima from the coast of the Bōsō peninsula (Sept. 1971).