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1.
The chemical and biological characteristics of surface waters in Jinhae Bay were investigated over four seasons to understand water quality in light of the growing industrialisation occurring within this area. Jinhae Bay includes four smaller bays: Masan; Hangam; Jindong; and Gohyun. The water quality in Jinhae Bay varied spatially and seasonally. The water quality of both Hangam Bay and Masan Bay was highly degraded, demonstrating high concentrations of ammonia, nitrate, chlorophyll a and particulate organic carbon. Contamination from sewage was the dominant cause of the water quality deterioration in these bays. Conversely, the water quality in Jindong Bay and Gohyun Bay was not as severely affected as that of the above two bays. Water quality in Jinhae Bay was particularly poor in summer when nutrient loading was highest due to the run-off associated with high precipitation. Principal component analysis indicated that nitrogen contamination was a major factor influencing the water quality of Jinhae Bay. The effective reduction in high-nitrogen discharges is essential to improve water quality in Jinghae Bay. 相似文献
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Izmir Bay is one of the most polluted estuaries in the Mediterranean Sea. The extent of pollution due to anthropogenic inputs in the Izmir Bay is investigated on the basis of nutrients together with basic oceanographic parameters. Significant phosphate, nitrogen (N) and iron (Fe) enrichment has been found in the water of inner Izmir Bay. The situation of middle Izmir Bay is also similar but not as critical as in inner Izmir Bay, whereas outer Izmir Bay shows 'typical Mediterranean coastal marine ecosystem' characteristics. The average atomic ratios of apparent oxygen utilization (AOU) and nutrient fractions (N and phosphorous [P]) have been found as AOU:P (49:1), AOU:N (48:1) and N:P (5:1). A comparative evaluation of these ratios leads to the conclusion that they are too low; e.g. such a low AOU:P ratio supports fairly high P enrichment. Principal component analysis (PCA) indicates that 31% of the variation in the data is related to enrichment parameters, i.e. dissolved inorganic phosphate, NH4+, reactive Fe, 15% is related to NO3-, pH and 13% is related to temperature and total Fe. Additionally, PCA shows that the middle Izmir Bay has an ecological transient character between the inner and outer Izmir Bay. 相似文献
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青岛市浮山湾、汇泉湾、崂山湾海滩与海底沉积环境分析 总被引：3，自引：0，他引：3
距今12000a，世界洋面已上升至今日海面以下60m处。而后海面继续回升，在距今6000a时，海面已上升到比今日海面还要高3～4m的位置，这就是汇泉广场下面存在海相地层的原因。也是唠山太清官门前存在干枯小泻湖的原因。大约在距今6000a时，青岛市的浮山湾、汇泉湾、唠山湾已经形成，并在海湾中，形成最初的海湾沉积。自那时以来，崂山湾变化不大；而浮山湾、汇泉湾则发生明显的变化。浮山湾展示为宽阔的沙滩形态，自上世纪60年代在燕儿岛建立船厂以来，大面积的沙滩已经消失。目前所见海岸完全为人造海岸，现已不存在海滩。汇泉湾与汇泉广场的填平有关，早期的海岸线，有可能到达中山公园的院墙一带。现在所见的第一海滨浴场也是人为建设所致。 相似文献
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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
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《Marine Chemistry》2001,73(3-4):215-231
In-situ benthic flux studies were conducted at three stations in Upper Galveston Bay twice during March 1996 to directly measure release rates of dissolved Mn, Fe, Ni and Zn from the sediments. Results showed reproducible increases with time in both replicate light and light–dark benthic chambers, resulting in average fluxes of −1200±780, −17±12, −1.6±0.6 and −2.4±0.79 μmol m−2 day−1 for Mn, Fe, Ni and Zn, respectively. Sediment cores collected during 1994–1996 showed that surficial pore water concentrations were elevated compared to overlying water column concentrations, suggesting diffusive release from the sediments. Diffusive flux estimates of Mn and Zn agreed in direction with chamber fluxes measured on the same date, but only accounted for 5–38% of the measured flux. Diffusive fluxes of Fe agreed with measured fluxes at the near Trinity River station but overestimated actual release in the mid and outer Trinity Bay regions, possibly due to inaccurate determination of the Fe pore water gradients or rapid oxidation processes in the overlying water at these stations.In general, measured fluxes of Mn and Ni were higher in the mid Trinity Bay region and suggested a mechanism for the elevated trace metal concentrations previously reported for this region of Galveston Bay. However, the fluxes of Fe were highest in close proximity to the Trinity River, supporting the elevated Fe concentrations measured in this region during this and other studies, and decreased towards middle and outer Trinity Bay. Trace metal turnover times were between 0.1 and 1.2 days for Mn, between 1.3 and 4.6 days for Fe, and between 27 and 100 days for Ni and 12–20 days Zn, and were considerably shorter than the average Trinity Bay water residence time (1.5 years) for this period. Comparing area averaged benthic inputs to Trinity River inputs shows the sediments to be a significant source of trace metals to Galveston Bay. However, while benthic inputs of trace metals were measured, water column concentrations remained low despite rapid turnover times for Mn and Fe, suggesting removal of these metals from the water column after release from the sediments. 相似文献
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The bedrock morphology of Start Bay, Southwest England, and the Structures within overlying sediments have been determined by a combined geophysical and geological survey. It has been established that the Skerries Bank consists of a drape of possibly coarse, unconsolidated material (bank deposits) overlying medium- to fine-grained silty sand (bay deposits). A break of slope in the bedrock surface, traced along the entire length of the Bay, and a step profile in the southern part of the Bay, may be either a legacy of submerged topography produced by vigorous tidal action, or alternatively the product of subaerial and marine processes. Other significant geological features in the Bay include infilled valleys, and “terraces” possibly pertaining to relict barrier beaches. 相似文献
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胶州湾大型底栖动物的丰度、生物量和生产量研究 总被引：3，自引：1，他引：2
为了研究胶州湾大型底栖动物的丰度、生物量和生产量,于2002年3月、6月、8月和12月,在胶州湾北部软底区、大沽河口、黄岛养殖区及养殖区邻域选取4个站位进行采样,对大型底栖动物进行了定量研究。共采到大型底栖动物138种,总平均丰度、平均生物量(湿质量)和年生产量(有机碳)分别为1 719个/m2,27 g/m2,2.2 g/(m2.a),初步估算,胶州湾大型底栖动物的总次级生产量为2.8万t/a。与渤海和南黄海大型底栖动物的丰度和生物量比较,丰度和生物量均低于这两个海域,但是胶州湾大型底栖动物的总次级生产量高于渤海。本研究对于了解胶州湾大型底栖动物现状及湾内养殖对大型底栖动物的影响具有重要的意义。 相似文献
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Sediment and water column data from four sites in North, Central and South San Francisco Bays were collected monthly from November 1999 through November 2001 to investigate the seasonal variation of benthic organic matter and chlorophyll in channel sediments, the composition and quality of sediment organic matter (SOM), and the relationship between seasonal patterns in benthic organic matter and patterns in water column chlorophyll. Water column chlorophyll peaked in the spring of 2000 and 2001, characteristic of other studies of San Francisco Bay phytoplankton dynamics, however an unusual chlorophyll peak occurred in fall 2000. Cross-correlation analysis revealed that water column chlorophyll at these four channel sites lead sediment parameters by an average of 2 to 3 months. Sediment organic matter levels in the San Francisco Bay channel showed seasonal cycles that followed patterns of water column production: peaks in water column chlorophyll were followed by later peaks in sediment chlorophyll and organic matter. Cyclical, seasonal variations also occurred in sediment organic matter parameters with sediment total organic carbon (TOC) and total nitrogen (TN) being highest in spring and lowest in winter, and sediment amino acids being highest in spring and summer and lowest in winter. Sediment chlorophyll, total organic carbon, and nitrogen were generally positively correlated with each other. Sediment organic matter levels were lowest in North Bay, intermediate in Central Bay, and highest in South Bay. C:N ratio and the ratio of enzyme hydrolyzable amino acids to TOC (EHAA:TOC) data suggest that SOM quality is more labile in Central and northern South Bay, and more refractory in North Bay and southern South Bay. 相似文献
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In April 1996, a massive algal bloom of the coccolithophorid Gephyrocapsa oceanica developed in both Chita Bay and Atsumi Bay which comprise the bay known as Mikawa Bay of Japan. It was the first record of such a bloom in this area. In Chita Bay, the bloom persisted until the middle of May, however in Atsumi Bay, it remained until early June. From the analysis of salinity, water temperature, and current velocity and direction data, it is considered that the following mechanism accounts for the occurrence and maintenance of the bloom: Before the bloom, the standing crop of phytoplankton was poor, resulting in relatively rich nutrients throughout the bay. Thereafter, with the influx of oceanic water into Mikawa Bay, high salinity occurred firstly in Chita Bay. Under these hydrographic conditions, the bloom occurred first in Chita Bay, and extended throughout the bay with the clockwise circulation of water into Atsumi Bay. In Chita Bay, the bloom was influenced by rainfall and G. oceanica flowed out from this area. Whereas, in Atsumi Bay, the bloom persisted for longer due to the clockwise circulation and another influx of oceanic water. 相似文献
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A Santa Marta JG Ferreira GC Pitcher J Lencart e Silva 《African Journal of Marine Science》2020,42(2):151-166
The carrying capacity for bivalve shellfish culture in Saldanha Bay, South Africa, was analysed through the application of the well-tested EcoWin ecological model, in order to simulate key ecosystem variables. The model was set up using: (i) oceanographic and water-quality data collected from Saldanha Bay, and (ii) culture-practice information provided by local shellfish farmers. EcoWin successfully reproduced key ecological processes, simulating an annual mean phytoplankton biomass of 7.5 µg Chl a l–1 and an annual harvested shellfish biomass of about 3 000 tonnes (t) y–1, in good agreement with reported yield. The maximum annual carrying capacity of Small Bay was estimated as 20 000 t live weight (LW) of oysters Crassostrea gigas, or alternatively 5 100 t LW of mussels Mytilus galloprovincialis, and for Big Bay as 100 000 t LW of oysters. Two production scenarios were investigated for Small Bay: a production of 4 000 t LW y–1 of mussels, and the most profitable scenario for oysters of 19 700 t LW y–1. The main conclusions of this work are: (i) in 2015–2016, both Small Bay and Big Bay were below their maximum production capacity; (ii) the current production of shellfish potentially removes 85% of the human nitrogen inputs; (iii) a maximum-production scenario in both Big Bay and Small Bay would result in phytoplankton depletion in the farmed area; (iv) increasing the production intensity in Big Bay would probably impact the existing cultures in Small Bay; and (v) the production in Small Bay could be increased, resulting in higher income for farmers. 相似文献
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A local-scale phase-resolving wave transformation model with CGWAVE is established in connection with a regional-scale coupled STWAVE-ADCIRC wave-current model for its application in the Half Moon Bay, Grays Harbor. Wave transformation from offshore to the harbor entrance is simulated by the STWAVE model which includes wave-current interaction. The STWAVE results provide incident wave conditions for the local-scale CGWAVE model at its outer boundary. A simple method is developed to take into ac- count the lateral variation of wave height in constructing the model's wave boundary conditions. The model was validated for three wave condition cases which yielded good agreement with field data. The validated model was applied to predicting nearshore waves in the Half Moon Bay and longshore transport parameters along the wave breaking line for the existing condition and three engi- neering alternatives. A comparative analysis indicated that storm waves that have a combination of long period and large height are the most destructive to the crenulate shoreline in the Half Moon Bay; both 152 m jetty extension (Alt. 2) and diffraction mound enlargement ( Alt. 3) would significantly reduce breaking wave height and longshore transport potential in the southwest comer of Half Moon Bay. 相似文献
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基于越南巴达棱湾2007年4月采集的42个表层沉积物样品及实测水文资料,分析越南巴达棱湾表层沉积物特征,并结合GSTA模型分析表层沉积物的运移趋势。结果表明:越南巴达棱湾表层沉积物以粗颗粒为主,在潮流和波浪的作用下呈中西部粗、东部细的分布特征;其西侧表层沉积物沿岸线自西南向湾内运移,中西近岸区沉积物垂直于岸线做离岸输移,在湾的东侧存在自东北向西南的运移趋势,并与从湾西运移过来的底沙相遇,形成运移辐聚区,并在余流的作用下,向西运移;"波浪掀沙,潮流输沙"是该地区表层沉积物输运的主要作用机制;在波浪的作用下,研究海域的海岸线处于侵蚀状态,有后退的趋势。 相似文献
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The growing demand of prawn protein in the world has been demanding an increasing catch of prawn from the sea which, however, fails to meet the needs due to over exploitation. This ease has always been a keen subject among us fishery seientists. With the support and guidance of the Provincial Government of Shandong, the Shandong Fishery Bureau has been carrying out a project of "the Ex- 相似文献
16.
细菌群落在水生生态系统中起着非常关键的作用。基于DNA和RNA高通量测序技术研究了福建三沙湾海域细菌的群落结构及其形成机制。结果发现：（1）三沙湾海域中共检测到细菌1 476个操作分类单元（OTUs）,其中γ-变形菌、α-变形菌、蓝细菌和拟杆菌为多样性最高的类群;（2）基于DNA和RNA高通量测序技术均发现这4种类群同时也是该海域细菌群落中的优势类群,但其代谢活性处于不同的状态,主要受到盐度、总氮、亚硝氮和无机磷酸盐浓度的调控;（3）三沙湾细菌群落结构在空间尺度上的分布存在差异,表现为地理位置上越相近的海区其细菌群落结构越相似。中性模型进一步分析发现,三沙湾海域细菌群落的形成主要受到中性过程的调控。本研究结果可为深入理解福建三沙湾海域中细菌群落结构及其形成机制提供理论依据。 相似文献
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Total mercury concentrations were determined in surficial sediments, eleven species of benthic organisms and six species of fish from Haifa Bay, Israel. The results show that essentially all of the shallow water zone of the Bay receives anthropogenic mercury. A mercury-cell chlor-alkali plant was identified as the source of pollution. Surficial sediments in the vicinity of the plant, containing up to 0·99 μg Hg/g dry weight, were up to 157 times enriched in mercury relative to an unpolluted area. Mercury levels in the benthic organisms reflected the levels in the sediments. Maximal concentrations reaching 38·7 and 18·2 μg Hg/g dry weight were found in the carnivorous gastropod molluscs Arcularia circumcinta and Arcularia gibbosula, respectively. In all fish species, specimens caught in Haifa Bay had higher mercury concentrations in the muscle tissue than specimens caught south of the Bay. A maximal value of 1·66 μg Hg/g wet weight was recorded in Diplodus sargus. 相似文献
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Joanna W. Doinsing Vienna Anastasia Admodisastro Laditah Duisan Julian Ransangan 《海洋学报(英文版)》2021,40(8):89-97
The population parameters of blood cockles, Tegillarca granosa in the intertidal zone of Marudu Bay, Sabah,Malaysia were investigated based on monthly length-weight frequency data(July 2017 to June 2018). A total of 279 cockle individuals with shell length and weight ranging from 27.7 mm to 82.2 mm and 13.11 g to 192.7 g were subjected to analysis. T. granosa in Marudu Bay showed a consistent moderately high condition index 4.98±0.86 throughout the year. The exponent b of the length-weight relationship was 2.6 demonstrating negative allometric growth. The estimated asymptotic length(L_∞), growth coefficient(K) and growth performance(?) of the T.granosa population in Marudu Bay were estimated at 86.68 mm, 0.98 a~(-1) and 3.87, respectively. The observed maximum shell length was 82.55 mm and the predicted maximum shell length was 84.44 mm with estimated maximum life span(t_(max)) of 3.06 years. The estimated mean lengths at the end of 2, 4, 6, 8, 10 and 12 months of age were 21.31 mm, 31.16 mm, 39.53 mm, 46.63 mm, 52.67 mm and 57.79 mm. Total, natural, and fishing mortalities were estimated at 2.39 a~(-1), 1.32 a~(-1) and 1.07 a~(-1). The exploitation level(E) was 0.45. Results of the current study also demonstrated that T. granosa in the Marudu Bay has two major recruitment peaks; one in March and another in October. The exploitation level revealed that natural stock of T. granosa in the Marudu Bay was approaching the maximum exploitation level. If such trend continues or demand for T. granosa is increasing,coupled with no effective fisheries management in place, possibility of the T. granosa population in the Marudu Bay to collapse is likely to elevate. 相似文献
19.
3个海域沙筛贝遗传差异的DNA分子标记研究 总被引：1，自引：0，他引：1
本文运用RAPD（random amplified polymorphic DNA）技术，对3个海域的沙筛贝进行了地理遗传差异分析．结果表明福建东山湾与厦门马銮湾沙筛贝的遗传距离为0．2764，深圳湾与马銮湾沙筛贝的为0．3067，深圳湾与东山湾沙筛贝的为0．3305．这说明马銮湾与东山湾的沙筛贝种群遗传距离较近，而东山湾与深圳湾的沙筛贝种群遗传距离较大．对厦门马銮湾沙筛贝的18S rDNA进行了测序，在基因库上查得同科另外3个种的18S rDNA序列，构建了分子系统发育树，发现沙筛贝与Mytilopsis leucophaeata同源性比较高． 相似文献
20.
Pelagic chaetognaths in Sagami Bay and Suruga Bay, Central Japan, were studied. Their community structure was very similar in both of these bays. Four genera and 26 species were identified. In Sagami Bay the habitat segregation by depths was clearly obtained. The population and species number of epipelagic (0–200 m) chaetognaths were larger in summer than in winter. The populations of meso- (200–500 m) and bathypelagic (500–1,000 m) species were smaller than that of epipelagic ones and fairly stable seasonally. 相似文献