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1.
利用实测资料分析重构了大亚湾和大鹏湾潮汐水位“双峰”现象,确定了浅水分潮的异常增长是潮位“双峰”现象的主要成因,其中四分之一日分潮和六分之一日分潮起着至关重要的作用。通过SCHISM模型构建大亚湾和大鹏湾附近海域高分辨率水动力模型,模拟结果表明近岸海域,在大亚湾以东,潮汐类型为不规则全日潮,以西为不规则半日潮,在两个海湾内均为不规则半日潮;研究海域的潮流均表现为不规则半日潮流。四分之一日分潮和六分之一日分潮在大亚湾和大鹏湾的不同变形过程是造成两个相邻海湾水文差异的直接原因。通过构建不同底摩擦强度、消除水底地形以及改变海湾水深的数值实验研究表明,分潮传播方向与水深变浅方向是否一致,是导致两个海湾潮波浅水变形不同的根本原因。 相似文献
2.
Characteristics of seiches in Onagawa Bay are investigated on the basis of observations at the bay head, Konorihama, from May 1972 to May 1973 and at the outside of the bay, Enoshima during the same period. At Konorihama seiches with the double amplitude of 7 to 11 cm occurred most frequently (63 percent of the total samples) and the maximum reached 31 cm. Short-time spectral analyses indicate that the periods of the spectral peaks shift considerably with the lapse of time, and that the location of the nodal line near the bay mouth moves offshore and inshore of Enoshima. The cause of these phenomena seems to be attributed to the change of incident angle of waves coming from the open sea to excite seiches. Amplitudes of the fundamental and of the lateral modes of seiches increase or decrease alternately with time, suggesting the energy transfer between these modes. Bay oscillations induced by remarkable atmospheric pressure-waves were observed. However, the amplitudes of the oscillations were within a few centimeters and dissipated in a few hours. 相似文献
3.
Benzo(a)pyrene (BP) in the sediment of Osaka Bay were determined. High concentration was found at two stations near the mouth of Shin-Yodo and off Kobe respectively (0.98g g–1 dry mud basis, 1.1g g–1). The concentration decreases regularly from the mouth of the river further into the bay. The other supplemental determination was carried on the sediment and the seawater of Keihin Canal. Notable BP concentration of 89g g–1 was observed in the sediment beneath the effluent outlet of a gasworks. The BP in the sediment near the ironworks was also considerable, while the BP was relatively less in the sediment beneath the effluent outlet of refineries. These data suggest that coke plants working in gasworks or ironworks may be the larger sources of BP than refineries. The results of Osaka Bay coincide with this hypothesis.Cadmium, lead, copper, zinc, nickel, ignition loss and fine sand content were measured from the same sediment samples of Osaka Bay. Cd, Pb, Cu and ignition loss showed the regular distributions which resemble to BP and accordingly, good correlations with BP. No significant correlations were found between BP and Ni, Zn and fine sand content which showed no regular distributions. 相似文献
4.
Carbon and nitrogen stable isotope ratios (13C and 15N) of surface sediments were measured within Osaka Bay, in the Seto Inland Sea in Japan, in order to better understand the sedimentation processes operating on both terrestrial and marine organic matter in the Bay. The 13C and 15N of surface sediments in the estuary of the Yodo River were less than –23 and 5 respectively, but increased in the area up to about 10 km from the river mouth. At greater distances they became constant (giving 13C of about –20 and 15N about 6). It can be concluded that large amounts of terrestrial organic matter exist near the mouth of the Yodo River. Stable isotope ratios in the estuary of the Yodo River within 10 km of the river mouth were useful indicators allowing study of the movement of terrestrial organic matter. Deposition rates for total organic carbon (TOC) and total nitrogen (TN) over the whole of the Bay were estimated to be 63,100 ton C/year and 7,590 ton N/year, respectively. The deposition rate of terrestrial organic carbon was estimated to be 13,200 (range 2,000–21,500) ton C/year for the whole of Osaka Bay, and terrestrial organic carbon was estimated to be about 21% (range 3–34) of the TOC deposition rate. The ratio of the deposition rate of terrestrial organic carbon to the rate inflow of riverine TOC and particulate organic carbon (POC) were estimated to be 19% (range 3–31) and 76% (range 12–100), respectively. 相似文献
5.
The currents and surface level oscillations in the Sea of Azov ensuing from contraction of the mouth of Taganrog Bay are computed using the grid technique on the basis of a numerical solution to the system of quasi-linear, degenerate, parabolic, partial derivative equations (shallow-water equations). It is demonstrated what changes are to be expected in the dynamics of the Sea of Azov should this project be realized. The computations were carried out for typical wind directions.Translated by Vladimir A. Puchkin. 相似文献
6.
渤海、黄海沿岸主要港湾假潮的基本特征 总被引：3，自引：0，他引：3
基于港湾假潮振动的基本原理，从渤海、黄海沿岸20个验潮站多年水位自记曲线资料获取假潮参数，并对其做了统计分析，给出了假潮的统计特征，还讨论了假潮形成的初步原因。结果表明，该海域主要港湾假潮出现具有明显的局地性、季节性和年际变化；夏季是大振幅假潮（振幅^1)≥80cm）的多发期，冬季基本上不出现；龙口港湾的大振幅假潮最为突出，最大振幅可达293cm；气压和风速、风向突变的良好配合，是发生大振幅假潮的主要原因。 相似文献
7.
Headland-bay beach equilibrium planform has been a crucial problem abroad to long-term sandy beach evolution and stabilization,extensively applied to forecast long-term coastal erosion evolvement and the influences of coastal engineering as well as long-term coastal management and protection.However,little concern focuses on this in China.The parabolic relationship is the most widely used empirical relationship for determining the static equilibrium shape of headland-bay beaches.This paper utilizes the relation to predict and classify 31 headland-bay beaches and concludes that these bays cannot achieve the ultimate static equilibrium planform in South China.The empirical bay equation can morphologically estimate beach stabilization state,but it is just a referential predictable means and is difficult to evaluate headland-bay shoreline movements in years and decades.By using Digital Shoreline Analysis System suggested by USGS,the rates of shoreline recession and accretion of these different headland-bay beaches are quantitatively calculated from 1990 to 2000.The conclusions of this paper include that (a) most of these 31 bays maintain relatively stable and the rates of erosion and accretion are relatively large with the impact of man-made constructions on estuarine within these bays from 1990 to 2000;(b) two bays,Haimen Bay and Hailingshan Bay,originally in the quasi-static equilibrium planform determined by the parabolic bay shape equation,have been unstable by the influence of coastal engineering;and (c) these 31 bays have different recession and accretion characters occurring in some bays and some segments.On the one hand,some bays totally exhibit accretion,but some bays show erosion on the whole.Shanwei Bay,Houmen Bay,Pinghai Bay and Yazhou Bay have the similar planforms,characterized by less accretion on the sheltering segment and bigger accretion on the transitional and tangential segments.On the other hand,different segments of some bays have two dissimilar evolvement characters.Dacheng Bay,Shenquan Bay,Hudong Bay,Wukan Bay,Fengjia Bay,Wuchang Bay,Lingshui Bay and Tufu Bay produce accretion on the tangential segment,erosion on the transitional segment and accretion on the sheltering segment.However,Guang’ao Bay,Haimen Bay,Jinghai Bay,Sanya Bay(a),Dajiao Bay,Hailingshan Bay,Hebei Bay,Fuhu Bay,Shuidong Bay,Wangcun Bay and Bomao Bay generate erosion on the tangential part,accretion on the transitional part and accretion on the sheltering part.It seems to imply some relations between headland-bay beach evolvement and controls on headland-bay beaches,which may possibly to classify headland-bay beach types and should be further studied. 相似文献
8.
Max M. Gibbs 《新西兰海洋与淡水研究杂志》2013,47(5):951-970
Abstract The influence of density stratification on sedimentation, suspension, and resuspension in Tasman Bay and Beatrix Bay, New Zealand, two contrasting coastal environments, was studied with specific reference to the implications for modelling aquaculture sustainability. Tasman Bay, an enhanced scallop (Pecten novaezelandiae Reeve) fishery, is a very large coastal indentation gently shelving to c. 20 m deep c. 10 km from shore and open to the Tasman Sea, whereas Beatrix Bay, an area of intense Greenshell? mussel (Perna canaliculus Gmelin) aquaculture, is a small (22 km2 × 30–40 m deep) enclosed embayment off the side of the nearby Pelorus Sound. Sediment trap arrays were used to determine the vertical fluxes of suspended solids and the associated chlorophyll component. Benthic chambers were used to investigate sediment nutrient regeneration. In summer, salinity gradients in both bays are minimal or non‐existent because of low inputs of fresh water and density stratification is mainly controlled by water temperature. The data from mid summer exhibited different spatial distribution patterns for detritus and phytoplankton biomass (as indicated by chlorophyll) in these two very different bays, although they had similar turbulent environments. The density discontinuity at the thermocline had a strong influence on settling of phytoplankton. There was evidence of upwards entrainment of suspended paniculate matter into the upper water column from the thermocline in Beatrix Bay. Benthic resuspension was estimated to contribute up to 90% of the suspended solids caught in sediment traps near the sea floor in both bays. The trapping rate of phytoplankton was thought to be dependent on species dominance. Possible mechanisms of resuspension included turbulence in the benthic boundary layer, and high velocities below the thermocline associated with internal seiches. The presence of a mid water column chlorophyll maximum in Beatrix Bay is discussed in terms of nutrient and light regimes at the thermocline, and species composition. In Tasman Bay, the chlorophyll maximum was thought to be caused by resuspension of benthic microphytes and their subsequent confinement in a thin layer (2–4 m thick) of high turbulence between the thermocline and the seabed. 相似文献
9.
10.
A coastal ocean -coordinate model of Monterey Bay (MOB) with realistic bottom topography and coastlines is developed using the Princeton Ocean Model (POM) and grid generation technique (GGT) to study the horizontal pressure gradient errors associated with the MOB steep topography. The submarine canyon in MOB features some of the steepest topography encountered anywhere in the world oceans. The MOB grids are designed using the EAGEAL View and GENIE++ grid generation systems. A grid package developed by Ly and Luong (1993) is used in this study to couple grids to the model. The MOB model is tested with both orthogonal and curvilinear nearly-orthogonal (CNO) grids. The CNO grid has horizontal resolution which varies from 300 m to 2 km, while the resolution of the orthogonal grid is uniform with x = 1.25 km and y = 1.38 km. These grids cover a domain of 180 × 160 km with the same number of grid points of 131 × 131. Vertical resolutions of 25, 35 and 45 vertical sigma levels are tested. The error in the MOB are evaluated in terms of mean kinetic energy and velocity against various grids, vertical, horizontal resolution and distributions, and bottom topography smoothing. Simulations with various grids show that GGT can be used as another tool in reducing -coordinate errors in coastal ocean modeling besides increasing resolution and smoothing bottom topography. Topographical smoothing not only reduces topographic slope, but changes realistic topography. A CNO grid with a high grid density packed along steep slopes and Monterey Submarine Canyon reduces the errors by 40% compared to a rectangular grid with the same number of grid points. The CNO grid is more efficient than the rectangular grid, since it has most of its grids over water. The simulations show that the presented MOB -coordinate model can be used with a confidence regarding horizontal pressure gradient error. 相似文献
11.
为解决海湾入海污染物总量控制中氮磷污染源强统计指标与海水水质标准因子不同的问题,本研究以罗源湾为例,采用现场调查取样和实验室分析结合的方法,通过分析罗源湾表层海水中的CDIN/CTN和CPO4-P/CTP的比值,将海水中DIN与PO4-P浓度的标准值转换成TN与TP的浓度.研究结果表明2009年罗源湾表层海水中的CDIN/CTN和CPO4-P/CTP的比值范围分别为0.12～0.97和0.16～0.91;其中夏季最低,CDIN/CTN和CPO4-P/CTP的比值平均为0.23和0.41,CDIN/CTN比值平面分布上呈湾顶和湾中部低、湾口高的分布趋势,CPO4-P/CTP比值平面分布上呈湾顶至湾口逐步递增的变化趋势;冬季最高,CDIN/CTN和CPO4-P/CTP的比值平均为0.67和0.68,CDIN/CTN比值平面分布上呈湾顶和湾口低、湾中部高的分布趋势,CPO4-P/CTP比值平面分布则相反;年均DIN和TN的浓度换算系数为0.48,PO4-P和TP的浓度换算系数为0.55;与其他海域相比,河口型海湾比值总体较高,沿岸海湾高于近海海域. 相似文献
12.
13.
研究了波致底切应力和二维辐射应力对悬沙的作用.首先对东山湾的水动力进行了数值模拟并与实测资料进行了对比检验,然后对东山湾悬浮泥沙进行了考虑波浪和不考虑波浪两种情况下的数值模拟并与实测资料进行了相关对比分析.在模式建立过程中,依据东山湾独特的窄口型半封闭河口海湾的特点,基于ECOMSED模式（2002）建立了东山湾三维水动力模型,并通过第三代海浪模式MASNUM加入了波浪对底切应力及辐射应力的影响,通过ECOMSED中的底边界层模型考虑了波浪增强底摩擦的作用,综合分析了东山湾的水动力及泥沙状况.结果表明在东山湾数值模拟中,该模式能较好地模拟这类海域的水动力及泥沙输运状况.在东山湾模拟计算中,潮流的作用强于波浪的作用,但考虑波浪因素后,泥沙模拟结果更好.在波浪的作用中,底切应力相比于二维辐射应力占有绝对的优势,两者相差2个量级以上,因此可以不考虑二维辐射应力的影响. 相似文献
14.
Masaya Toyokawa Kaoru Aoki Satoshi Yamada Akira Yasuda Yusuke Murata Tomohiko Kikuchi 《Journal of Oceanography》2011,67(2):209-218
We surveyed the distribution of colonies of polyps of Aurelia
aurita sensu lato (s.l.) in Mikawa Bay, Japan. First, we surveyed the distribution of ephyrae of A. aurita s.l. at 75 stations encompassing the whole of Mikawa Bay in early 2008. A total of 37 ephyrae were sampled mostly from fishing
ports. Ephyrae were most abundant around the islands located near the mouth of the bay, and decreased from the western part
to the eastern part of Mikawa Bay. Next, we selected five fishing ports in Mikawa Bay where ephyrae occurred and surveyed
the underside of floating piers and underwater overhangs of wharfs. We found dense colonies of polyps of A. aurita s.l. under nearly all of the floating piers at the two islands located near the mouth of the bay. Fitting a logistic regression
model to the dataset showed that the percentage coverage of Aurelia polyps was significantly greater at the two islands compared with the other locations. In addition, the coverage of Aurelia polyps was greater when the coverage of other fouling organisms was in the range of 65–90%, and the coverage of Aurelia polyps was lower on floating piers with a vinyl surface and on concrete wharfs. The combined distribution of polyp colonies
of A. aurita s.l. in Ise Bay and Mikawa Bay suggested that A. aurita s.l. in the two bays probably forms a single population and shoals of medusae mainly originate from protected harbors along the
mouth-part of the bays. 相似文献
15.
南海北部沿岸海洋站的假潮 总被引：1，自引：0，他引：1
收集和分析了南海北部沿岸15个海洋站所在港湾发生假潮的资料，并对其中较大振幅的典型假潮个例，进行了港湾基态自然周期分析和假潮振动的频谱分析。研究发现，假潮最大振幅振动多发生在天文潮的高潮或低潮期间；根据海湾地形尺度用梅立恩（Merian）公式计算得出的海湾基态自然周期；和根据资料曲线估计得出的假潮周期，以及功率谱分析得出的周期，三者非常接近。从本文研究所得结果来看，这些海湾的较大振幅假潮多发生在春、夏季，且都和风速、风向以及气压的剧烈变化有关。这些大气扰动在春天多为冷空气南下，在夏季多为热带气旋活动。研究认为，假潮的发生很可能是大气振动通过外海表面波作为中间机制，与港湾自由态振动之间产生耦合共振的结果。 相似文献
16.
We report on a year's study of spatial and seasonal patterns of zooplankton abundance in Port Phillip and Westernport Bays, July 1982 to August 1983. These two bays, closely adjacent on the southern coast of Victoria, Australia, differ in several respects: Port Phillip is a nearly landlocked bay with a broad basin, while Westernport is an open tidal embayment with extensive mud and seagrass banks. Both bays have a resident zooplankton fauna distinct from that of Bass Strait. Although these resident communities have many species in common, patterns of abundance and dominance are quite different. We found that the holoplankton of Port Phillip was about half copepods, mostly Paracalanus indicus, with 23% Caldocera and 21% larvaceans. Westernport Bay zooplankton was dominated by Acartia tranteri, with no resident cladoceran fauna. Bass Strait species were more often found in Westernport than in Port Phillip Bay, but the resident community of Port Phillip Bay was more similar to that of Bass Strait than to that of Westernport.Although this study was undertaken in an exceptionally dry year, the available historical data show that the overall patterns found in 1982–1983 are typical for these bays. The differences in community composition probably relate to differences in depth profile, predator abundance, and suspended matter between the bays. 相似文献
17.
Akira Kurata 《Journal of Oceanography》1974,30(4):199-202
Cobalt contained in the sediments from Maizuru Bay and Wakasa Bay was determined by the atomic absorption method. Cobalt content in the surface layer of the bottom sediments averaged 15.2 and 6.7g/g dry matter in Maizuru Bay and in Wakasa Bay, respectively. The vertical distribution of cobalt was almost uniform in the column of bottom sediments. Geographically, the cobalt content in sediments tended to be inverse proportion to the distance from the coast in Wakasa Bay. Considering the distribution of cobalt, it is reasonably concluded that cobalt is not a limiting factor to the production of vitamin B12 by microorganisms in these regions. 相似文献
18.
The commercially important sergestid shrimp,Sergia lucens (Hansen), has long been considered an endemic species of Japan because it had been found only in Suruga Bay and neighbouring waters. Recently, however, a considerable amount of a similar shrimp was caught by trawl nets off Tung-kang, southwestern Taiwan. This shrimp is distributed at depths of 100–300 m on the continental slope, around a deep submarine canyon adjacent to the mouth of the Kao-ping River. A morphological comparison with specimens from Suruga Bay reveals that the shrimp is identical toS. lucens. However, a slight difference in the patterns of water-soluble proteins was observed in a thin layer isoelectrophoretic examination. A difference was also observed in the spawning season of the two populations, indicating sexual and geographic isolation. Considering the distribution and phylogeny of the family Sergestidae, based on a possible evolutionary development from a benthic neritic organism to a pelagic oceanic one along the generaSicyonella-Sergestes-Sergia, it is assumed thatS. lucens entered a lower epipelagic habitat in the coastal waters from the warm oceanic mesopelagic habitat of the original stock. A hypothesis is proposed that speciation ofS. lucens from the original stock occurred when it was trapped in a semi-enclosed inlet (the paleo-East China Sea Gulf) that existed at the present Okinawa Trough during the late Pliocene to early Pleistocene. The inlet was deep, but had a neritic environment due to drainage from ancient large river systems, including the paleo-Yangtze River. The species expanded its distribution to the neighbouring waters during the warm interglacial period. However, a rapid rise in sea level after 14,000 years significantly changed the environmental conditions in the distributional area and the species could not expand into a neritic environment, which was too shallow for survival. Accordingly,S. lucens populations remained only in Suruga Bay and Tung-kang waters, where the environment has remained stable for the last 17,000 years or more. The two areas have the following common characteristics:
- A large amount of fresh water is discharged into the deep submarine canyon adjacent to the river mouth.
- The northeastern part is surrounded by land so that a direct inflow of boreal water into the environment is blocked.
- Warm Kuroshio extension water intrudes and mixes with water from the rivers, and for Suruga Bay there is a current system that keeps distribution of the eggs and larvae restricted to the local habitats.
19.
Yoshinari Ambe 《Journal of Oceanography》1973,29(1):1-7
The contents of alkylbenzenesulfonate (ABS) in the bottom sediments were analyzed for the inner part of Tokyo Bay and five inflowing rivers. Methylene blue active substances (MBAS) was extracted from the dired sample with methanol-benzene mixture.After the concentration of MBAS was determined by colorimetry, the ratio ABS/MBAS was estimated by an infrared spectrum of MBAS-MB complex. The net content of ABS was calculated from these two values.The ABS contents in the surface of the bottom sediments of the rivers and sea ranged 1.959g/g and 014.1g/g dry weight, respectively. The contents of ABS in the river sediments reflected the degree of pollution of each river by urban waste waters. From the results of the analysis of the core samples of sea sediment at two points containing ABS only in the upper layer, the average rate of sedimentation of the bottom muds in the inner part of Tokyo Bay since the usage of ABS began was estimated as 3 cm/year and 7 cm/year respectively. 相似文献
20.
M. V. Ramana V. Subrahmanyam K. S. Krishna A. K. Chaubey K. V. L. N. S. Sarma G. P. S. Murty G. S. Mittal R. K. Drolia 《Marine Geophysical Researches》1994,16(3):237-242
Total magnetic intensity and bathymetric surveys were carried out in the northern Bay of Bengal between 6° to 11° 45 N latitudes and east of 84° to 93° 30 E longitudes. The hitherto known 85° E Ridge is characterised as a subsurface feature by a large amplitude, positive magnetic anomaly surrounded by Mesozoic crust. A newly identified NE to NNESSW trending magnetic anomaly between 7° N, 87° 30 E and 10° 30 N, 89–90° E may be one of the unidentified Mesozoic lineations in the northern Bay of Bengal. The Ninetyeast Ridge is not associated with any recognizable magnetic anomaly. The Sunda Trough to the east of the Ninetyeast Ridge is characterised by a positive magnetic anomaly. A combined interpretation, using Werner deconvolution and analytical signal methods, yields basement depths ~ 10 km below sea level. These depths are in agreement with the seismic results of Curray (1991).Deceased 24 December 1991 相似文献