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1.
锦州湾沾污沉积物急性毒性的海洋端足类检验   总被引:13,自引:1,他引:12  
1992年9月 ̄1993年1月对锦州湾沾污沉积物的海洋端足类急性毒性效应进行了研究。从锦州湾湾顶到湾口沿西南--东北方向每2km等距离采集27个表层沉积我校 品,应用海洋端足类A mpelisca abdita对这些样品进行了10d直流式急性毒性检验,检验指标为死亡率。结果表明,五里河河口处受试生物死亡率最高,为100%,从湾顶该河口处沿东北方向随着距离增加,死亡率逐渐递减,笔架山处最低,仅为2.  相似文献   

2.
连云港港区60个表层沉积样品的定量分析表明,与港区水动力、底形等沉积环境条件相适应,该区有孔虫埋葬群可分为口门、湾中、湾顶三大群个组合,并可进一步区分出若干六个亚类组合:(A)湾项浅水区——丰度值最低,胶结壳有孔虫含量最高,活体含量高;(B)鸽岛沉积区——与A紧邻,但以丰度值高相区别;(C)西岸码头深水区——水深,丰度高,活体少,浮游个体多;(D)东侧浅水区——水浅,埋葬群特征与C相近;(E)涨潮三角洲区--沉积物粒径小,丰度高,胶结壳含量最低;(F)口门高能区——以沉积物粒径较低区别于E区.  相似文献   

3.
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   

4.
The sources and distributions of polycyclic aromatic hydrocarbons (PAH) and aliphatic hydrocarbons are characterized in seventeen sediments from a highly river-influenced sedimentary environment off the southwestern coast of Washington. The major hydrocarbons are land-derived, introduced as preformed compounds and display long-term stability in sediment cores. A series of PAH of anthropogenic origin and two naturally derived compounds, retene and perylene, dominate the PAH composition in these sediments. Plantwax n-alkanes are the major aliphatic hydrocarbon constituents. Aliphatic hydrocarbons of marine origin, pristane and a series of four acyclic, multibranched C25 polyolefins, are also observed in many sediments. The concentrations of these marine-derived hydrocarbons decrease to negligible levels rapidly with sediment depth from the sea-sediment interface, suggesting degradation.In general, the major land-derived hydrocarbons are concentrated in the midshelf silt deposit which extends northwestward along the continental shelf from the Columbia River mouth. A quantitatively more minor, natural series of phenanthrene homologs, also of terrestrial origin, is preferentially advected further offshore and deposited in continental slope sediments. These distributions are consistent with recognized particle associations for these compounds and sediment dispersal processes in this coastal environment. Sediment core records suggest the present pattern of dispersal has persisted for at least the past century and possibly since the Late Pleistocene.  相似文献   

5.
以气相色谱-质谱法(GC-MS)分析并结合外标法,定量测定了2009年4月—2010年2月6个航次桑沟湾海域水体和沉积物中常见的8种有机磷农药,探讨了该海域有机磷农药组成以及时空分布特征.结果表明:桑沟湾水体中共检出有机磷农药6种,其中甲基对硫磷、马拉硫磷和对硫磷等3种有机磷农药在各航次均有检出.沉积物中有机磷农药含量的水平分布呈现由湾口向湾内海域逐渐降低的趋势.该海域水体中有机磷农药含量呈现10月份较高,4月、6月和8月份次之,12月和 2月份最低的月份分布特征.与国内外类似水体相比,桑沟湾海域中总有机磷农药含量处于轻度污染水平,甲基对硫磷、马拉硫磷等单组分含量也处于较低水平.  相似文献   

6.
To study the historical and current status of the environmental levels of organotin compounds in Chinhae Bay in southeast Korea, mussels (Mytilus edulis galloprovincialis), oysters (Crassostrea gigas) and sediment cores were analysed for tributyltin (TBT) compounds. TBT concentrations were higher in oysters (mean: 0.25 μg TBT-Sn/g dry wt) than in mussels (mean: 0.20 μg TBT-Sn/g dry wt). The major sources of TBT are in the inner bay, and the highest TBT concentrations of 0.50 μg TBT-Sn/g (mussels) and 0.74 μg TBT-Sn/g (oysters) were observed at the site adjacent to the port. Concentrations of TBT decreased sharply with distance from the inner bay toward the outer bay and there was little TBT in the outer bay. A significant correlation was observed between this distance and the tissue TBT content of oysters and mussels. The concentration and percentages of TBT in sediment cores decreased with depth as a result of debutylation. Half-lives of TBT and dibutyltin (DBT) in sediments were 6.9 and 11.6 y, respectively. The TBT concentrations in mussels were higher than those in sediments by a factor of 4–7.  相似文献   

7.
Hydrophobic organic contaminants (HOCs) may be used as tracers of particle dynamics in aquatic systems. Internal cycling of polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) were studied in the mesohaline Chesapeake Bay to assess the role of resuspension in maintaining particle and contaminant inventories in the water column, and to compare settling and suspended particle characteristics. Direct measurements of sediment resuspension and settling conducted in conjunction with one of the sediment trap deployments indicate reasonable agreement between measurements of particle flux using the two different methods. Organic carbon and PCB concentrations in settling solids collected in near-surface sediment traps were remarkably lower than concentrations in suspended particles collected by filtration during the trap deployments, but higher PAH concentrations were found in the settling particles. The different behaviors of PAHs and PCBs in the settling particles are due to their different source types and association to different types of particles. Sediment trap collections in near bottom waters were dominated by resuspension. Resuspension fluxes of HOCs measured 2 m above the bay bottom were as high as 2.5 μg/m2 day for total PCBs and 15 μg/m2 day for fluoranthene, and were 25 and 10 times higher than their settling fluxes from surface waters, respectively. HOC concentrations in the near bottom traps varied much less between trap deployments than HOC concentrations in the surface traps, indicating that the chemical composition of the resuspended particles collected in the near bottom traps was more time-averaged by repeated resuspension than the surface particles.  相似文献   

8.
To estimate the influence of mercury emitted from submarine fumaroles, the horizontal and vertical distribution of mercury in sediment of Kagoshima Bay was studied. The fumaroles are located in the northern bay head area, and the sediment samples had been taken from 52 points throughout the bay with a gravity core sampler. The core samples obtained were cut at a thickness of 1–2 cm and used for measurements. The total concentration of mercury in surface sediment in the northern and central areas of the bay was 51–679 μg kg− 1 (average 199 μg kg− 1, n = 22) and 23–100 μg kg− 1 (average 55 μg kg− 1, n = 30), respectively. The highest value was obtained in the vicinity of the fumaroles. The mercury concentration in sediment near the fumaroles varied with depth, which may reflect the variation in fumarolic activity. A successive extraction method was applied to the speciation of mercury in the sediment. The results showed that sediment taken in the vicinity of submarine fumaroles contained a higher percentage of mercury bound with organic matter.  相似文献   

9.
This study briefly investigated sediment transport by tidal currents in Gomso Bay, on the mid-west coast of Korea during the summer season. Hydrodynamic measurements with benthic tripods (TISDOSs) show that near-bed suspended sediments are transported toward the bay mouth along the low-water line of tidal flats in the southern part of the bay, while they are directed offshore in front of the major tidal channel at the bay mouth according to tidal asymmetry. However, suspended sediments in the main body of sea water, observed from transect and anchor-site measurements, indicate a consistent incoming toward the uppermost tidal flats. A brief episode of relatively strong winds from the west and southeast displays that wind waves can yield the near-bed suspended sediment concentrations (SSC) overwhelming the SSC by tidal currents alone in the remaining duration.  相似文献   

10.
2007年和2010年在厦门湾及邻近海域进行底质表层沉积物和柱状岩心样品采集,并进行粒度分析及粒度参数计算,获得了研究区底质表层和柱状沉积物样品的粒度分布特征.结果表明,厦门湾海域沉积物类型多样,以粉砂质砂和砂质粉砂为主.平均粒径介于?1.5Φ~7.5Φ之间.采用 Gao-Collins粒径趋势分析方法,发现九龙江口的沉积物主要呈东南方向净输运,而大金门南侧海域沉积物则有向九龙江口输运的趋势,同安湾内沉积物由海岸向湾中央输运;厦门东部海域沉积物向北输运,翔安南部海域沉积物向同安湾口以及澳头近岸输移.对柱状岩心进行放射性同位素210Pb 测年分析,计算得到九龙江口沉积速率为2.62 cm/a,进而探讨了九龙江口的沉积环境演化特征,研究成果可为区域资源开发和环境保护提供科学依据  相似文献   

11.
根据2018年1月冬季航次的水文实测资料,详细分析了大亚湾海水温度(T)、盐度(S)的分布特征。整体而言,观测海区海表相对于海底具有高温低盐的特征;同时,无论是表层还是近底层,大亚湾湾内的海水相对于湾外都呈现高温低盐的特征。观测期间,应是受到大亚湾核电站温排水的影响,湾内西侧存在一个高温中心。盐度的差异在近底层更加明显,低盐中心位于大亚湾的湾顶和大亚湾的中部海域,而高盐中心则主要分布于湾口西侧及惠东以东附近海域。太阳辐射和潮流变化是影响大亚湾温度、盐度变化的两大重要因素。其中,太阳辐射的影响主要局限于表层3~4 m,对近底层海水的影响较小;其加热效应使湾内和湾口附近的表层海水都表现出明显的昼夜变化。由潮汐和温度、盐度的对应关系可知,潮流对湾内温度、盐度的影响较大,而对湾外温度、盐度的影响较小。  相似文献   

12.
During the summer of 1997, sediment core samples were taken at 25 stations in Santa Monica Bay. Toxicity testing was performed on 4-cm sections of the entire length of each core using purple sea urchin fertilization and amphipod survival tests. The sea urchin test identified sections as being toxic at six stations, all located near current or former Hyperion Treatment Plant (HTP) wastewater outfall locations. The amphipod test identified sections from 17 stations as having toxic sediments. The stations having toxic sediments were scattered throughout the bay and toxicity was identified at numerous core depths. Spatial and temporal patterns indicated that toxicity was most strongly associated with the historical disposal of municipal wastewater sludge. Many of the sections toxic to the amphipods did not have chemical levels expected to cause toxicity and were in locations where a source of toxicity was not apparent.  相似文献   

13.
Observations of water movement and sediment transport were made from a fixed platform at an intertidal location in the mouth of the Eden estuary. The effects of wave activity on water movement and suspended sediment fluxes were evaluated, and an empirical relationship between suspended sediment concentrations and near bed water movement is described. The circulation of water in St Andrews Bay indicates a residual movement onshore near to the bed. Onshore movement of sediment in the mouth of the estuary is indicated by suspended sediment fluxes and bedload transport (determined from bedform migration). The relative roles of suspended sediment and bedload transport are discussed. Morphological changes in the estuary mouth over the three-year survey period are relatively small and indicate a stable environment.  相似文献   

14.
Field studies have established the concentrations of naphthalenes in bay sediments and water in the vicinity of an oil separator platform and their effects on the benthic fauna. Fifteen stations were occupied monthly, from July, 1974 to December, 1975, along three transects extending from the separator platform outfall outwards for a distance of 4·0 to 5·6 km. A lesser number of stations were occupied from April, 1974 to June, 1974. Bottom sediments at each station were analysed for total naphthalenes content and for number of species and individuals. All stations were located in 2 to 3 m of water. The outfall was located 1 m off the bay bottom.There was a definite correlation between sediment naphthalenes concentration and number of species and individuals. As expected, the first station, located 15 m from the outfall, had the highest concentration of naphthalenes of all stations sampled. The naphthalenes levels dropped sharply from the outfall to the stations located 75 m from the platform where levels were about 20–50% of those found 15 m from the outfall. Naphthalenes concentrations then decreased gradually to near background levels at stations farther out. Hydrocarbon concentrations in bottom water 15 m from the outfall were three orders of magnitude lower than those in the full strength effluent, but sediments 15 m from the outfall had hydrocarbon concentrations four times as great as in the full strength effluent. There were approximately four orders of magnitude more hydrocarbons in the sediment than in the overlying water.The bay bottom was almost completely devoid of organisms within 15 m of the effluent outfall. Stations located 150 m from the outfall had severely depressed benthic faunas but not to the extent of stations nearer the outfall. Stations located 455 m from the platform were unaffected. Both numbers of species and individuals increased with distance from the platform and reached a peak at the first station medial to the control on each transect (685 to 1675 m from the platform) and then dropped at the control station. Physical environmental factors such as temperature, salinity, water depth and sediment type were essentially the same at all stations.The temporary use of a second outfall located 275 m from the main platform outfall resulted in a rapid build up of naphthalenes in surrounding sediments which persisted for at least six months following the termination of use of the second outfall. The benthic fauna was also severely depressed in the vicinity of the second outfall. The use of multiple outfalls, located some distance apart, appears to be more harmful than the use of a single outfall.Trinity Bay, Texas, the site of this investigation, has a mean depth of 2·5 m. The bay water is highly turbid due to the presence of a high concentration of clay-sized particulate material. The brine outfall was located approximately 1 m above the bay bottom. These special conditions undoubtedly contributed significantly to the observed impact of the brine. Therefore, extrapolations from the results of this study to offshore oil production and brine disposal should be made with extreme caution.  相似文献   

15.
黄河口及近海表层沉积物中烃类化合物的组成和分布   总被引:6,自引:0,他引:6  
为探讨黄河口近海表层沉积物有机质中烃类化合物的分布特征及输运过程,2003年9月采集了南北两个断面表层沉积物样品,对沉积物中正构烷烃和多环芳烃进行了分析,结果表明,黄河口表层沉积物中正构烷烃和多环芳烃的含量分别为0.38~2.55和0.371~0.650μg/g。在南北断面两种烃类化合物的分布明显不同:北断面受石油平台影响,烃类化合物在口门含量较高;南断面受黄河输入影响,由于大颗粒易于沉降,而吸附烃类化合物的能力较强的小颗粒易长距离输运,使这两种烃类化合物的含量从河口到近海整体呈上升的趋势。与北断面相比,南断面受水生源影响相对较弱,而且水生源的贡献随着离岸距离的增加而加强,在最大浑浊带后水生源急剧增强;在南断面多环芳烃主要来源为热解源,北断面多环芳烃受热解源和石油污染的共同影响。  相似文献   

16.
浙江乐清湾现代沉积与悬沙质量浓度分布特征及意义   总被引:2,自引:0,他引:2  
毛龙江  殷勇  郭伟  朱大奎 《海洋科学》2005,29(10):93-96
通过对乐清湾野外考察、表层沉积物的粒度分析和水样的悬沙质量浓度分析,探讨了乐清湾现代沉积和悬沙质量浓度分布特征。研究结果表明,乐清湾现代沉积主要以细颗粒沉降为主,粉沙和粘土总含量占90%以上;悬沙质量浓度具有从湾口向湾内递减的变化趋势,湾口悬沙质量浓度为0.2~0.25kg/m^3,而湾内质量浓度小于0.01kg/m^3。半封闭性海湾和以外海来沙为主的物质来源共同决定沉积物的特征及悬沙质量浓度的空间变化规律,而泥沙来源及沉积过程的研究将为港湾治理工程提供重要的依据参数。  相似文献   

17.
The concentrations of a number of trace metals (Co, Ni, Cu, Zn, Ag, Cd and Hg) have been determined in sediments from cores collected in the Southampton Water region. Measurements of total hydrocarbons were also made on several of the cores. Markedly elevated concentrations of copper, up to 362 μg/g dry wt, were found in sediments which were collected close to the discharge points of oil refinery outfalls and which also showed concentrations of total hydrocarbons considerably greater than the background levels for the estuary. The results of selective chemical extractions showed that much of the copper was present in the non-lattice fraction of the sediment. Although the concentrations of Co, Ni, Zn and Cd were significantly correlated with those of copper in the core showing the highest concentrations of this element, these metals were not enhanced in comparison with the levels found in several other parts of the estuary. Variations in concentrations of metals in sediments throughout the estuary were not correlated with differences in organic carbon content.  相似文献   

18.
为了解胶州湾水体和表层沉积物营养环境状况及其主要影响因素,于2019年8月在胶州湾30个站位点采集了海水和表层沉积物样品,并于2021年5月在胶州湾沿岸采集了18个站位点的水样,对水体溶解无机态营养盐浓度和组成以及表层沉积物中总有机碳、总氮、总磷及生物硅含量和碳、氮稳定同位素(δ13C、δ15N)进行了分析。结果表明,胶州湾内水体和沿岸水体中溶解无机氮、溶解无机磷和溶解硅酸盐浓度空间分布相近,高值均位于湾东北部,主要受到河流输入和沿岸污水排放的影响,低值主要出现在湾中部和湾口处。结合近30年来的历史数据分析发现,胶州湾夏季营养盐浓度在1990-2008年期间呈持续上升的趋势,政府实施的污染物总量控制措施以及河流径流量下降使得2006年以来营养盐浓度呈现下降的趋势,该变化在空间上主要体现为大沽河氮、磷输入量的减少及其对应的湾西部营养盐高值的消失。胶州湾氮、磷营养盐输入的不平衡使得“磷限制”在2000年后逐渐加剧。胶州湾表层沉积物中总有机碳、总氮、总磷含量高值均集中于东北部和东部沿岸,结合生物硅和水体营养盐含量分析显示,这主要是河流与排污输入及其...  相似文献   

19.
近海湾口潮汐沉积特征通常以地质资料进行描述,而很少以地球物理资料进行描述。或仅利用某种地球物理资料进行分析。本文通过利用多波束、侧扫声呐、单道地震、多道高分辨率地震和磁法等多种地球物理勘探方法和技术,针对胶州湾近海湾口潮汐沉积的地球物理特征进行了初步研究,获得了近海湾口潮汐沉积典型的地球物理特征。  相似文献   

20.
胶州湾海水中悬浮体的分布及其季节变化   总被引:2,自引:0,他引:2  
海水中的悬浮体包含有机物和无机物,有机物主要为有机碎屑颗粒,例如植物碎屑、浮游生物等;无机物主要是无机碎屑矿物、粘土矿物,也有少量硅质生物骨骼。海水中无机颗粒物质能通过吸附作用,从海水中有效地富集有机溶解物质。海水中天然有机物的分布、变化与浮游生物的活动密切相关,在海洋食物链中占有重要地位,海水中的颗粒有机物是某些游泳动物和底栖动物的食物,因此,海水中有机物的存在不仅对海洋生物有一定的生态学意义,而且对海洋无机元素的存在形式和地球化学转移过程都有直接影响。 胶州湾是一个典型的半封闭海湾,平均水深7m,面积390km2,自然环境优良,水产资源丰富,因此胶州湾的生态环境、生物资源及生态系统持续发展的研究对胶州湾的综合开发利用具有十分重要的意义。胶州湾海水中悬浮体的分布与变化是胶州湾生态环境研究中的一个重要组成部分。本文根据胶州湾海水中悬浮体的定点观测资料,阐明了胶州湾海水中悬浮体平均含量的分布及其季节变化特征,分析了影响悬浮体含量变化的主要因素。  相似文献   

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