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1.
Tetsuo Yanagi 《Journal of Oceanography》1999,55(3):439-448
Seasonal variations in freshwater, salt, phosphorus and nitrogen budgets of Hakata Bay, Japan were investigated from April 1993 until March 1994. The internal sink of dissolved inorganic phosphorus (DIP) and nitrogen (DIN), and the internal source of dissolved organic phosphorus (DOP) and nitrogen (DON) predominate in the bay. This means that the production of organic matter is larger than respiration, and atmospheric CO2 is absorbed in the water column of Hakata Bay. Denitrification is more dominant than nitrogen fixation in the bay. Compared to Tokyo and Mikawa Bays, Hakata Bay is harder to eutrophicate, mainly due to the shorter residence time of freshwater. 相似文献
2.
大亚湾及其邻近海域冬、夏季各14个临时水位观测点1个月的实测潮位资料显示:各站的水位曲线均呈现明显的"双峰"现象,且湾顶比湾口更为明显。本文采用了调和分析方法,给出M_2、S_2、K_1、O_1四个主要分潮及M_4、M_6、2MS_6三个浅水分潮的振幅和迟角同潮图,分析大亚湾的主要潮汐特征,探讨了浅水分潮对双峰结构的贡献,并采用交叉谱分析对余水位与风的相关性进行了讨论。结果表明:(1)大亚湾海域各主要分潮振幅均由湾口向湾顶递增;高潮发生时间由湾口向湾顶推迟;涨潮历时均大于落潮历时;平均潮差在湾顶达到最大;(2)大亚湾内属于不正规半日潮,而考洲洋及其湾外海域则属于不正规全日潮;(3)大亚湾内浅水效应明显,从湾口至湾顶,六分之一日分潮的振幅呈5—7倍的增长,主导了大亚湾潮波系统的形变;(4)分潮重构结果显示,四分之一日和六分之一日浅水分潮(尤其是2MS_6分潮)的异常增长,是导致大亚湾潮汐双峰现象的主要原因;(5)冬季大亚湾内各点的余水位与风速呈现正相关,相关系数均在0.53以上;(6)周期为0.45—0.53 d的沿岸风对各站余水位的影响最大。 相似文献
3.
4.
Jeongwon Kang Han Jun Woo Seok Jang Kap-Sik Jeong Hoi-Soo Jung Ha Gi Hwang Jun-Ho Lee Jin Hyung Cho 《Ocean Science Journal》2016,51(3):305-316
Rare earth elements (REEs: La-Lu) in surface sediments collected from the mouth and middle tidal flats of Gomso Bay, South Korea, in August 2011 and May 2012 were analyzed to investigate the fine-grained sediment provenance. The upper continental crust (UCC)-normalized light REEs (LREEs: La to Nd) were more enriched than the middle REEs (MREEs: Sm to Dy) and heavy REEs (HREEs: Ho to Lu), resulting in large (La/Yb)UCC (1.9 ± 0.4) to (Gd/Yb)UCC (1.4 ± 0.2) ratios. The monthly (La/Yb)UCC values differed between the mouth and middle tidal flats due to deposition of fine-grained sediments that originated from distant rivers (the Geum and Yeongsan) and the Jujin Stream, located on the southern shore of the inner bay. We observed relative reductions in the (La/Yb)UCC value and REE content in the sediments from the mouth of the bay compared with those from Jujin Stream sediments. Confined to the middle tidal flat around the KH Line of Jujin Stream, the sediments, most enriched in LREEs but depleted in Eu, were distributed in August as strong Jujin Stream runs. Here, we suggest that an increase in LREE/HREE and decrease in MREE/LREE ratios can be used as a proxy to identify the Jujin Stream provenance in mixed riverine sediments and to trace Jujin Stream sediments within the Gomso Bay tidal flat, especially in the summer rainy season. 相似文献
5.
A time-series sediment trap was deployed from December 1994 to February 2002 at the mouth of Tokyo Bay (35°03′ N, 139°40′
E; water depth, 850 m). Sinking particles were obtained with a time interval of one week at a depth of approximately 100 m
above the sea floor. Observed total mass fluxes varied from 3.3 to 226.7 g/m2/day with an average of 28.0 g/m2/day. Concentrations of rare earth elements, Al, Ca and Si in particulate materials were measured. The combustible fraction
at 450°C is assumed to be equivalent to the organic matter content. Contents of biogenic materials, namely organic matter,
opal and calcium carbonate, were about 30% and the content of lithogenic material was about 70%. Using La/Yb ratios of particles
from the sediment trap and Tama-gawa River and surface sediment of Tokyo Bay, it was estimated that about 50% of the lithogenic
particles collected in the sediment trap at the mouth of Tokyo Bay originated from resuspended surface sediment in Tokyo Bay.
An increasing trend of Opal/CaCO3 ratio in the sinking particles was found in the spring season. It is suggested that the relative increase of diatoms is due
to the decreasing dissolved inorganic nitrogen input into Tokyo Bay. 相似文献
6.
7.
胶州湾水交换及湾口潮余流特征的数值研究 总被引：5，自引：3，他引：5
利用基于普林斯顿海洋模式建立的胶州湾及临近海域潮汐潮流数值模型,结合胶州湾口走航式声学多普勒海流剖面仪(ADCP)测流资料,研究了胶州湾口的潮(余)流特征,并在潮流模型的基础上耦合建立了水质模块,模拟了胶州湾的水交换过程。考虑M2,S2,K1,O1,M4和MS4六个主要分潮,胶州湾口潮流场的模拟与ADCP观测数据吻合较好。外湾口水道上的潮流非常强,大潮期间观测到201 cm/s的峰值流速。团岛岬角的两侧分别存在一个流向相反的余流涡旋,两涡旋在团岛附近辐合,形成了57 cm/s的离岸强余流。整个胶州湾平均水体存留时间为71 d,平均半交换时间为25 d。胶州湾水体交换能力在空间分布上有很大差异:湾口海域最强,向湾顶逐渐减弱。湾内存在两个弱交换区,分别位于湾的西-西南部和东北端,水体存留时间多超过80 d,湾西局部水域最长达120 d,而半交换时间也大多超过40 d。潮流场的结构、强度,以及与湾口距离的远近是造成湾内水交换能力空间差异的主要原因。 相似文献
8.
2010-2011年胶州湾叶绿素a与环境因子的时空变化特征 总被引：2，自引：1，他引：1
2010年4、6、8、10月和2011年1、3月在胶州湾开展了6个航次的综合调查,研究了表层海水温度、盐度、营养盐和叶绿素a浓度的时空变化特征。调查期间,总无机氮(DIN)、磷酸盐(PO4)和硅酸盐(SiO3)多呈现东北部湾边缘高,而湾内和湾口低的空间分布特征。季节变化表明,DIN和PO4主要受养殖排放、河流径流输入和浮游植物生长消耗的影响,呈现初夏和秋季高,夏末和冬季低的特点;而SiO3主要受河流径流输入和浮游植物消耗的影响,呈现夏、秋高,而冬、春低的特点。营养盐浓度和结构分析表明,胶州湾存在PO4和SiO3的绝对和相对限制;SiO3限制尤其严重,是控制胶州湾浮游植物生长的主要环境因子。SiO3和PO4的限制主要表现在冬季,几乎遍布整个海湾;夏季降水可有效缓解海域的SiO3限制。叶绿素a浓度呈现春、夏季高,秋、冬季低的季节分布,温度、营养盐浓度与结构和季节性贝类养殖活动是控制胶州湾叶绿素a浓度时空分布的关键因素。 相似文献
9.
B. Mialet F. Azémar T. Maris C. Sossou P. Ruiz M. Lionard S. Van Damme A. Lecerf K. Muylaert N. Toumi P. Meire M. Tackx 《Estuarine, Coastal and Shelf Science》2010
The spatial spring distribution of Eurytemora affinis (adults and C5) in the Scheldt estuary (Belgium) brackish and freshwater reaches was studied in between 1996 and 2007. The bulk of the E. affinis population being generally situated in the brackish water reach (salinity > 0.5); we studied which environmental factors are responsible for its recent sporadic occurrence in the freshwater estuarine reach. Using PLS analysis, it is shown that its presence upstream is limited by a sufficient oxygen concentration (>4 mg l−1) that is associated with temperature. Not only are the environmental conditions in the upstream zone important, but also the frequent presence of an O2 minimum zone in the mid-estuary (O2 min < 1.3 mg l−1) seems to block the movement of the downstream E. affinis population in an upstream direction. Occasionally, the bulk of the population is however situated upstream. During these periods, high E. affinis abundance was also observed in the Durme tributary. Our findings suggest the possibility to use E. affinis as an “indicator” species of water quality, but also lead us to stress the necessity to consider conditions over the entire estuary when studying restoration effects, not exclusively in the zone of interest. 相似文献
10.
尖笔帽螺是一种分布广泛的翼足类生物,在食物网与生物地球化学循环中起着重要作用。2020年7月,大亚湾出现高密度尖笔帽螺,给当地生态安全带来潜在风险。文章利用浮游生物成像仪（PlanktonScope）,以定点的方式对大亚湾西南海域的环境因子与尖笔帽螺密度进行采样,并对大亚湾高密度尖笔帽螺的分布特征进行研究。结果显示：在水平方向上,尖笔帽螺主要分布于西部湾口及长湾附近海域,其他海域分布相对较少;在垂向上,尖笔帽螺多分布于高温低盐的表层,低温高盐的下层水体分布较少;体长分布方面,湾口西部及其北侧海域尖笔帽螺体长较长,小辣甲西侧、北侧海域尖笔帽螺体长偏短,湾口中部海域体长远小于其他区域。通过分析结果发现,此次大亚湾湾内高密度尖笔帽螺存在随外海海流输入的可能;温盐分布结果表明,尖笔帽螺多出现在海水表层,其垂直分布可能也受海水分层及海流的影响。通过对尖笔帽螺分布特征的归纳与讨论,可以为后续该种生物的进一步溯源提供参考。 相似文献
11.
To investigate both the role of tides on the timing and magnitude of Submarine Groundwater Discharge (SGD), and the effect on benthic nitrogen biogeochemistry of nitrate-enriched brackish water percolating upwards at the seepage face, we conducted a study of SGD rates measured simultaneously with seepage meters and mini-piezometers, combined with sets (n = 39) of high resolution in-situ porewater profiles describing NH4+, NO3−, Si(OH)4 and salinity distribution with depth (0–20 cm). Sampling took place during two consecutive spring tidal cycles in four different months (November 2005, March, April and August 2006) at a backbarrier beach face in the Ria Formosa lagoon, southern Portugal. Our results show that the tide is one of the major agents controlling the timing and magnitude of SGD into the Ria Formosa. Intermittent pumping of brackish, nitrate-bearing water at the beach face through surface sediments changed both the magnitudes and depth distributions of porewater NH4+ and NO3− concentrations. The most significant changes in nitrate and ammonium concentrations were observed in near-surface sediment horizons coinciding with increased fraction of N in benthic organic matter, as shown by the organic C:N ratio. On the basis of mass balance calculations executed on available benthic profiles, providing ratios of net Ammonium Production Rate (APR) to Nitrate Reduction Rate (NRR), coupled to stoichiometric calculations based on the composition of organic matter, potential pathways of nitrogen transformation were speculated upon. Although the seepage face occasionally contributes to reduce the groundwater-borne DIN loading of the lagoon, mass balance analysis suggests that a relatively high proportion of the SGD-borne nitrogen flowing into the lagoon may be enhanced by nitrification at the shallow (1–3 cm) subsurface and modulated by dissimilatory nitrate reduction to ammonium (DNRA). 相似文献
12.
Shuichi Watanabe Naoto Higashitani Nobuo Tsurushima Shizuo Tsunogai 《Journal of Oceanography》1994,50(4):415-421
The concentration of methane in seawater was determined approximately once a month for one year from August 1990 to July 1991 at a station close to the center of Funka bay (92 m depth) and some supplementary observations were also carried out. The concentration of methane was usually increased with increasing depth, suggesting that methane was emitted from the bottom of the bay. While highly variable both spatially and temporally, the emission was intense in March and April, a period immediately after the spring bloom of phytoplankton. The maximum of methane found in the intermediate water suggests its source from the slope of the bay. The concentration of methane in the surface water changed seasonally and also interannually. The annually averaged flux of methane transferred to the atmosphere in the bay was estimated to be 6×10–3 gCH4m2/day. The coastal zone in the world may be a significant source of the atmospheric methane, although its source strength has yet to be accurately estimated from more data in different coastal seas. 相似文献
13.
From 1980 to 1995, in August, the bottom layer of Osaka Bay was occupied by cold, nutrient-rich water compared with that observed
during both previous and subsequent decades. To investigate the mechanisms for the intrusion of bottom-layer cold water into
Osaka Bay, the intrusion into Osaka Bay via the Kii Channel is simulated using a finite-volume coastal ocean model with unstructured
triangular cell grids. The initial conditions, boundary conditions, and surface temperature given to the model are obtained
from daily reanalysis data provided by the Japan Coastal Ocean Predictability Experiment. The model shows that cold water
uplifted on the eastern side of the Kii Peninsula is propagated westward at 1.0 m/s as a coastal boundary current; it reaches
the Kii Channel mouth when the Kuroshio axis is located around 74 km south of Cape Shionomisaki. However, the modeled cold
water mass at the Kii Channel mouth does not intrude further to the north of the Kii Channel; therefore, another mechanism
is required to explain the cold-water intrusion into the bottom layer of Osaka Bay. A plausible explanation is the estuarine
circulation established by the freshwater supply at the bay head. When the river runoff is included in the model without forced
vertical mixing, the temperature in Osaka Bay decreases 6.6 days later than the temperature decreases at the Kii Channel mouth.
Furthermore, the shoreward current speed in the bottom layer of the modeled estuarine circulation is 15 cm/s, which provides
the mechanism required for the cold water mass to pass the Kii Channel. 相似文献
14.
M. Ribas-Ribas J.M. Hernández-Ayón V.F. Camacho-Ibar A. Cabello-Pasini A. Mejia-Trejo R. Durazo S. Galindo-Bect A.J. Souza J.M. Forja A. Siqueiros-Valencia 《Estuarine, Coastal and Shelf Science》2011
The role of coastal lagoons and estuaries as sources or sinks of inorganic carbon in upwelling areas has not been fully understood. During the months of May–July, 2005, we studied the dissolved inorganic carbon system in a coastal lagoon of northwestern Mexico during the strongest period of upwelling events. Along the bay, different scenarios were observed for the distributions of pH, dissolved inorganic carbon (DIC) and apparent oxygen utilization (AOU) as a result of different combinations of upwelling intensity and tidal amplitude. DIC concentrations in the outer part of the bay were controlled by mixing processes. At the inner part of the bay DIC was as low as 1800 μmol kg−1, most likely due to high water residence times and seagrass CO2 uptake. It is estimated that 85% of San Quintín Bay, at the oceanic end, acted as a source of CO2 to the atmosphere due to the inflow of CO2-rich upwelled waters from the neighboring ocean with high positive fluxes higher than 30 mmol C m−2 d−1. In contrast, there was a net uptake of CO2 and HCO3− by the seagrass bed Zostera marina in the inner part of the bay, so the pCO2 in this zone was below the equilibrium value and slightly negative CO2 fluxes of −6 mmol C m−2 d−1. Our positive NEP and ΔDIC values indicate that Bahía San Quintín was a net autotrophic system during the upwelling season during 2005. 相似文献
15.
A three-dimensional （3-D） finite volume coastal ocean model （FVCOM） was used for the study of water cir culation and seawater exchange in the Benoa Bay, Bali Island. The M2 tidal component was forced in open boundary and discharge from six rivers was included in the numerical calculation. The M2 tidal elevation produced by the FVCOM has a good agreement with the observation data. The M2 tidal current is also suc cessfully calculated under the ebb tide and flood tide conditions. The non-linear M2 tidal residual current was produced by the coastline geometry, especially surrounding the narrow strait between the Serangan Is- land and the Benoa Peninsula. The tidal residual current also generated two small eddies within the bay and one small eddy in the bay mouth. The salinity distribution influenced by river discharge could be success- fully calculated, where the numerical calculation and the observation results have a good correlation （r2） of 0.75. Finally in order to examine the seawater exchange in the Benoa Bay, the Lagrangian particle tracking method and calculation of residence time are applied. The mechanism of particle transport to the flushing of seawater is depicted clearly by both methods. 相似文献
16.
大规模增养殖区柘林湾叶绿素a的时空分布 总被引：9，自引：1，他引：9
柘林湾是粤东一个大规模海水增养殖区和赤潮重灾区.2001年7月至2002年7月对柘林湾及其周边水域(共设19个站位)进行的叶绿素a含量周年调查结果表明,调查海区叶绿素a站位实测值年变化为0.01~3.26 mg/m3,均值为0.56 mg/m3.平面分布的基本格局表现为湾顶黄冈河内与湾口外侧海域的叶绿素a含量明显高于湾内的,湾内外侧和东部水域的叶绿素a含量明显高于湾内内侧和湾西部的.结合同步调查的水化数据得知,柘林湾是一个高营养盐、低叶绿素的海湾,其原因可能与高密度、大规模海水增养殖业引起的水流不畅、水下光照减弱和养殖贝类的摄食等有关.柘林湾叶绿素a含量的季节变化显著,最高值出现在2001年夏季8月,最低值出现在冬季1月和2002年7月,其中2002年7月的叶绿素a含量仅为2001年7月的1/10左右.这种巨大的年际间变化显然与2001~2002年厄尔尼诺现象导致粤东地区于2002年春夏期间气候异常、干旱少雨、径流剧减和调查海区浊度大幅升高有关. 相似文献
17.
To clarify the time change in water exchanges between Ise Bay and the adjacent ocean, repeated hydrographic observations were
conducted along the longitudinal section in Ise Bay. The results show that the mixing condition at the bay mouth (Irago Strait)
changed fortnightly in summer. During the spring tides, the strait water below the pycnocline was well-mixed and nearly homogeneous.
By contrast, it was weakly stratified during the neap tide. There is a strong negative correlation between the tidal range
and the density difference between the upper and lower layers at the strait. In summer, the intrusion depth of oceanic water
into the bay and consequent hydrographic conditions inside the bay changed frequently according to the tidal strength. During
the spring tides a prominent bottom front was created at the bay mouth, indicating that the strait water, which is a mixture
of oceanic and bay waters, intruded through the middle layer. On the other hand, during the neaps, cold and saline oceanic
water intruded through the bottom layer into the bay. The intrusion depth is significantly correlated with the tidal range.
It is considered that the wellmixed strait water, which has a density equivalent to the middle layer inside the bay, is lighter
than the bottom bay water and thus intrudes through the middle layer during the spring tides, while insufficient mixing makes
the bottom water at the strait heavier than the bay water, leading to the bottom intrusion during the neap tides. 相似文献
18.
通过对诏安湾海域6个站位的水文泥沙观测和181个表层沉积物样品的粒度分析,结合海湾水深地形,应用Gao?Collins粒径输运模型和系统聚类分析方法,分析研究了福建诏安湾海域的粒度参数分布特征、表层沉积物的运移趋势和沉积环境划分及其动力机制.结果表明,诏安湾表层沉积物共6种类型,以黏土质粉砂和砂为主,平均粒径介于0.5... 相似文献
19.
The community composition,abundance and culturablity of heterotrophic bacterioplankton in the Dapeng Bay of the South China Sea were investigated by morphological method,bacterial cultivation and biochemical methods over an annual cycle.Aeromonas and Pseudomonas were the predominant genera among the Gram-negative bacteria.The bacterioplankton abundance fluctuated from 2.07×10 8 to 2.44×10 9 cells/dm 3 ,and culturable bacteria abundance ranged between 0.1×10 6 and 16.07×10 6 CFU/dm 3 .The Culturablity of heterotrophic bacteria ranged between 0.01% and 1.31%.The relationship between bacterial culturablity and the environmental factors was also studied in different sites of the Dapeng Bay.Throughout the bay,a significantly positive relationship was evidenced between bacterial culturability and temperature,meanswhile bacterial culturability was significantly inversely related with salinity.The positive relationship was shown at the central bay while a negative relationship was observed at the bay mouth and there was no significant correlation at top bay between bacterial culturablity and chlorophyll a of sea water.A positive relationship was found between culturability and DIN all the bay,but DIP showed a significantly negative relationship with bacterial culturability only at the mouth of the bay. 相似文献
20.
The spatial distribution of stage-specific abundance and reproduction of the copepod Paracalanus parvus were studied from October 2005 to September 2006 in the Jiaozhou Bay. This copepod occurred continuously in this bay throughout the year. The species reached the lowest abundance in April and peaked in June. From October to December, distribution center mainly occurred in offshore water and at the mouth of the bay. In winter, early copepodites and adults gradually decreased and till February, most of the population was only comprised of CIV–CV stages. Overwintering copepodites matured in March and males tended to mature before female. From May to September, each stage occurred in the population and gradually reached high abundance. Temperature and chlorophyll a (Chl-a) concentration in the three stations can't clearly explain the seasonal variation in stage-specific abundance, so we surmised the important effect of the Yellow Sea. Egg production rate (EPR) reached its lowest in winter and peaked in June at 60.8 eggs female−1 day−1 in nearshore water. In the warming period, EPR in nearshore water was statistically higher and EPR > 10 eggs female−1 day−1 lasted longer than that in offshore water, showing the importance of nearshore water for recruitment of P. parvus. Our study showed that EPR was positively related to temperature and total chlorophyll a in offshore water and mouth of the bay. In nearshore water, the relationships between EPR and temperature and Chl-a in three size fractions were not the same as those in offshore water, suggesting complicated ecosystem in such a eutrophic area in warming period. 相似文献