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1.
本文对1978年4月8日在黄海水域青岛附近捕获的一头成体抹香鲸(Physeter cotodon Linnaeus,1758),对其骨骼进行了详细的系统观察、测量和研究,分头骨、躯干骨和附肢骨三部分作了描述。抹香鲸骨骼的特点是头骨巨大,约为骨架全长的1/3。颅顶形成巨大凹陷,翼骨发达,枕骨愈合,无泪骨;头骨左右明显不对称,左骨质鼻孔比右边大;左鼻骨发达,右鼻骨退化;左前颌骨较短,向后仅达鼻孔,右前颌骨后延超过鼻孔达颅凹后壁。寰椎游离,其它6枚颈椎愈合;肩胛骨高大于宽,第11对肋发育不全,扁直、短小,是鲸类骨骼中最特殊的。  相似文献   

2.
结合国家自然科学基金项目现场调查,于1997年7月在莱州湾东部金城镇近海水域发现一尾大型腹孔总目的软骨鱼类,经鉴定:系为双吻前口蝠鲼(Mantabirostris),隶属于鲼形目(Myliobatiformes)蝠鲼科(Mobulidae)前口蝠鲼属(Manta)。该鱼量为世界温暖水域广分布种,但通常只分布到我国东、南海区,偶见于黄海南部,而出现于渤海水域则属首次。前口蝠鲼以口前位和仅下颌具一齿带,分离头鳍位于头部两侧和细小铺石状牙齿为特征,而与口下位和上下颌均具齿带的蝠鲼属(Mobula)的种…  相似文献   

3.
在整个黄海水域,夏季存在着范围广阔的深层冷水块。习惯上根据地域分布的不同,把地处北黄海的冷水块叫“北黄海冷水团”,地处南黄海的叫“南黄海冷水团”这两冷水块连成一体通称“黄海冷水团”。赫崇本是我国最早分析黄海冷水团的基本属性和消长变化的学者之一;而后,管秉贤分析了黄海冷水团的水温变化和环流结构,并进一步确认黄海冷水团是冬季保留下来的。近几年来我国学者对黄海冷水团的成因和水文、环流结构又有不少新的研究。例如,袁业立提的热生模式较好地讨论了北黄海冷水团中心区域的热结构和环流结构;Guo Binghuo(郭炳火)根据南黄海冷水团分裂成两个低温中心,指出:围绕南黄海冷水团存在着大小两个气旋式冷水团环流。万国铭等1)依据经典的水团分析技术指出:南黄海冷水团仅分布于123°E以西的狭小区域,而123°E以东的广阔水域则为黄海暖流底层水所占据。赵保仁提出潮混合对黄海冷水团的边界起着重要的控制作用。以上几种观点,对进一步分析黄海的水团和环流结构都有着启发意义。 本文的主要目的,是依据1984年7月中美联合调查所获得的水文资料(站位见图1)和部分历史资料来阐明南黄海冷水团内部的复杂结构。分析结果表明,夏季南黄海深层冷水团内部,仍然存在着春季保留下来的具有高温高盐性质的黄海暖流水系的扩张现象。这一扩张现象似可理解为与黄海暖流同源但已被切断联系的黄海暖流残迹在黄海冷水团内部继续前进的反映。因此,夏季黄海冷水团可进一步划分为具有高温高盐性质的“黄海暖流水”和具有低温低盐性质的“黄海本地冷水”两个次级水团。在这两种水团之间,存在着明显的锋面和显著的混合现象,在锋面处还可以观测到由双扩散产生的两水团之间的相互侵入现象。  相似文献   

4.
刁焕祥 《海洋科学》1986,10(6):30-34
黄海冷水(又称黄海冷水团)是我国近海水文特征的重要现象,自本世纪二十年代以来,日本和我国海洋物理学家陆续对其进行了较多的研究。近年来又见有该水域的水化学特性报道,其中顾宏堪首先研究了黄海水域夏季溶解氧垂直分布最大值,继而刁焕祥等指  相似文献   

5.
本文的研究基于文莱湾浅水域的一头野生伊洛瓦底海豚水声定位信号的调查数据。在记录期间,有一艘渔船突然开启发动机,惊扰了其附近的一头伊洛瓦底海豚,接着渔船开始两次连续追逐海豚。这期间海豚回声定位信号的变化情况被记录下来。当伊洛瓦底海豚受惊吓被追逐时,信号的声压级、每分钟嘀嗒声信号串的发生次数、每个嘀嗒声信号串中的脉冲个数和平均脉冲间隔都发生了相应的变化。平均的脉冲间隔在事件发生的瞬间立即增大,并在追逐期间呈现轻微下降趋势。脉冲间隔的增大对应着探测距离的增加,代表着海豚对未知区域的探索能力,制约着它的逃离速度。数据记录结果的分析表明,伊洛瓦底海豚会根据外界干扰对发出的回声定位信号进行调整,改变自己对潜在危险的探查能力。分析结果同时提醒我们需要随海豚生存环境的噪声进行管理,避免突然的发动机操作或者追逐它们。  相似文献   

6.
黄海西部介形虫分布再探   总被引:2,自引:0,他引:2  
本研究从黄海西部175个表层沉积样品中共获得介形虫壳瓣13000余枚,并将其分类为75属142种.介形虫丰度的高值主要出现在40m以浅的水域,由南向北呈带状分布.分异度H(S)由南向北递减,与水温的变化趋势相一致.由射阳至长江口,在辐射状沙脊分布的水域H(S)的平均值达到最高值.通过对69个主要属种进行Q型因子分析,划分出6个与海洋环境相对应的介形虫组合分布区域.通过追踪介形虫属种在黄海、东海的地理分布,再次证实了介于两海域间的种分布不连续所对应的乃是亚热带-暖温带界线.  相似文献   

7.
《海洋技术学报》2006,25(1):F0003-F0004
FHY1小型多参数海洋环境监测浮标 1 概述 FHY1型浮标设计为随波浮标。通过搭载不同类型的传感器可以完成气象,波浪,水文和水质参数的测量;采取太阳能蓄电池供电方式,保证在14d缺乏日照的情况下,系统能够正常供电;可使用卫星通讯,也可使用短波通讯。适用于中国的渤海,黄海,东海和南海水域,能在沿海水域完成实时测量和数据传输。  相似文献   

8.
利用基于电子探针(EPMA)的耳石Sr:Ca比和Sr含量分析方法研究了长江口水域刀鲚、凤鲚、带鱼和长吻鲍的生活履历及生活史型。结果发现,刀鲚中除存在淡海水洄游性个体生活史型外。还存在出生并生活于河口或近海的非洄游性个体生活史型,其平均耳石Sr:Ca比在不同水环境履历的基准值为:淡水〈2.0×10^-3、河口(3.5—6...  相似文献   

9.
黄海冷水域水化学要素的垂直分布特性   总被引:1,自引:0,他引:1  
黄海夏季深层冷水(简称黄海冷水), 又称为黄海冷水团, 已为海洋物理学家进行过较多的研究。该水域化学研究开展较晚,近年来顾宏堪首先报道了黄海夏季溶解氧垂直分布最大值与黄海冷水密切相关。黄海冷水与其它水团一样,理、化、生物等特性是相互关联的统一体。遗憾的是,迄今尚未见到有关于此的多学科综合性的研究报道。 本文根据1959年海洋调查资料,对黄海冷水域主断面水文化学要素的垂直分布特性进行了研究,并讨论了该冷水形成及诸参数变化的原因。  相似文献   

10.
应用1983年11-1984年7月观测的温度、盐度和光学衰减系数C作为划分水团指标,采用逐步聚类分析方法划分南黄海水团,并对南黄海的悬浮体分布和光学性质进行了分析讨论。结果表明,将海水光学衰减系数作为划分水团指标是可行、有效的。分析结果为:夏季表层有黄海水团、黄海冷水团和长江冲淡水,底层只有黄海水团和黄海冷水团,并且存在着混合带。秋季水团基本上保持着夏季型,但长江冲淡水缩小,不存在混合带。南黄海底层水的主要光学特征具有明显的区域性,并大体上可分为如下区域:(1)中、东部区域,相当于黄海底层冷水区域,最大光学衰减系数大于9;(2)西部区域,黄海水团区域,呈东南向条状,其轴心区的光学衰减系数C>1;(3)西南部区域,包括苏北沿岸水与黄-东海混合水;(4)西北部区域,相应于黄海底层浑水侵入区。最后,用称重法获得的悬浮总量(SS)与C之间有线性关系:C=0.366SS+0.50,相应的线性关系数为0.83。  相似文献   

11.
For more than a decade, interactions between humans and Hawaiian spinner dolphins in their resting bays have been a concern for members of the general public, managers, scientists, policymakers, and tour operators. Hawaiian spinner dolphins are the target of a large wildlife tourism industry due to their predictable daytime resting behavior and presence in coastal areas. Using results from passive acoustic monitoring between January 2011 and March 2013 on the Kona coast of Hawai‛i Island, USA, the relative importance of four known Hawaiian spinner dolphin resting bays, the contribution of anthropogenic noise including vessel noise to the four bay soundscapes, and the dolphins' response to human activities were assessed. Here the findings are summarized and visualized and recommendations are provided for action to regulate directed dolphin watching and ensuing unauthorized takes under the Marine Mammal Protection Act of 1972. These findings and recommendations have implications for the federal government's ongoing efforts to implement rules that protect Hawaiian spinner dolphins in their resting bays.  相似文献   

12.
We describe the structure of a toothed cetacean community around the island of Mayotte (South-West Indian Ocean, 45°10′ E, 12°50′ S), using data collected from small boat-based surveys conducted between July 2004 and June 2006. In all, 16 odontocete species were recorded. Diversity (Shannon-Weaver index) was particularly high along the outer slope of the barrier reef. Patterns of spatial distribution underscore the existence of three main cetacean habitat types: the inner lagoon (Indo-Pacific bottlenosed dolphin Tursiops aduncus and humpback dolphin Sousa chinensis), the outer-reef slope (spinner dolphin Stenella longirostris, pantropical spotted dolphin S. attenuate and melon-headed whale Peponocephala electra) and oceanic waters deeper than 500 m (e.g. Blainville's beaked whale Mesoplodon densirostris). Group characteristics were highly variable among species, with oceanic small delphinids characterised by larger group sizes than strictly coastal and non-delphinid oceanic species. The outer slope of the barrier reef appears to be of primary importance in terms of density and diversity of odontocetes around Mayotte. Results support the hypothesis that a number of cetacean species, particularly several delphinid species, are dependent on coral reef complexes.  相似文献   

13.
Mayotte in the southwest Indian Ocean is characterized by high dolphin diversity. They may coexist within a fairly small area around the island because they exploit neither the same preferential habitats nor the same resources. This preliminary study aimed to investigate ecological niche segregation among these delphinid communities: the Indo-Pacific bottlenose dolphin, Tursiops aduncus, the pantropical spotted dolphin, Stenella attenuata, the spinner dolphin, Stenella longirostris, and the melon-headed whale, Peponocephala electra. Two approaches were used. Habitat preferences were investigated by analysing dolphin sighting data and associated physiographical characteristics. Resource partitioning was explored by analysing C and N stable isotopes in skin and blubber biopsies. Only T. aduncus, which showed clear association with coastal habitats in the lagoon, differed from the others in terms of habitat preferences, characterised by shallow depth and slope, and proximity to the coast. All other species shared similar oceanic habitats immediately outside the lagoon, these being of higher depth and slope, greater distance from the coast and were not discernable by discriminant analysis. The two Stenella species and the melon-headed whale displayed very high overlap in habitat physiographic variables. The analysis of stable isotopes confirmed the ecological isolation of T. aduncus and revealed a clear segregation of P. electra compared to the two Stenella that was not apparent in the habitat analysis. This may reflect ecological differences that were not observable from diurnal surface observations.  相似文献   

14.
The ecosystem approach to fisheries management (EAFM) methodology is currently considered the preferred option for long-term sustainability of fisheries and ecosystem services and is widely popularised. Manuals, guidelines and training have been given to many nations, but the actual existence and execution of an EAFM plan is rare. The applicability and relevance of biological and socioeconomic tools to follow EAFM planning guidelines in a data absent area were explored in Kalpitiya, northwest Sri Lanka, where there is a population of spinner dolphins that the local community are especially dependent on through tuna-dolphin association fishing and dolphin-watching tourism. This paper provides background to the design and collection of information leading to the formulation of an EAFM management plan. Scoping and the determination of a fishery management area were completed through stakeholder consultations using a combination of interviewer-administered questionnaires, interviews, meetings, dolphin distribution data and existing management plans. Threats and stakeholder prioritisation were compiled and the final agreed fisheries management area covers a total area of 2445 km2 adjacent to the Kalpitiya peninsula. The completed EAFM plan contains 4 goals, 16 actions and 72 sub-actions agreed by stakeholders. It was concluded that both willingness of higher level stakeholders responsible for implementing regulations and working with grass-root level stakeholders are critical in developing a realistic and implementable EAFM plan. This work also highlights how data absence should not remain the bottleneck that hinders moving forward with EAFM approaches.  相似文献   

15.
福建海洋兽类及其分布   总被引:4,自引:1,他引:4  
李树青 《台湾海峡》1997,16(4):479-485
通过对在福建沿海地下发掘出土的海兽骨骼,古文献比较分析研究,提出了福建省古代7种海兽分布名录;依据采集和调查到的现生海兽标本,提出了福建省18种海兽的种类和分布。  相似文献   

16.
A series of land-based surveys were conducted at two vantage points of known dolphin abundance in Hong Kong. The purpose of this study was to determine the behavioral response of Indo-Pacific humpback dolphin (Sousa chinensis) to vessel traffic. Results indicated that dolphins dove for a longer duration in areas of heavy vessel traffic or when there was the presence of an oncoming vessel. Dependent upon the type of vessel and the relative distance, dolphins might flee, continue their ongoing activity, perform a new activity, or approach the vessel. Whilst slow-moving vessels appeared not to cause immediate stress on the dolphin community, fast-moving vessels often cause disruption of behavior and social life. In order to ensure a better environment for the animals, we suggest that proactive conservation measures such as the creation of a marine park, rules and regulations for dolphin watching activities, and regional control of vessel speed should be implemented.  相似文献   

17.
Critically endangered Māui dolphin (Cephalorhynchus hectori maui) are found exclusively off the west coast of New Zealand’s North Island. One important data gap troubling efforts to reduce the current unsustainable level of bycatch is the limited information on the offshore and alongshore limits of their range. Passive acoustic monitoring studies could address this data gap, but Māui dolphin habitat is dominated by a sandy substrate that can shift greatly in the strong local currents. In February 2016, a short pilot CPOD deployment was thus attempted as a first step to see if the equipment could be deployed and recovered in the area and if the data collected would be viable, with a second unit deployed inside a harbour for comparison with earlier TPOD data. The pilot was largely successful, and roughly 11% of all minutes in the core habitat location contained detections of clicks attributed to Māui dolphin. A visual inspection of the data suggests some trends with diel and tidal patterns. Further work of this type is thus recommended.  相似文献   

18.
赵丽媛  陶翠花  许敏  祝茜 《台湾海峡》2012,31(2):195-201
首次将SRAP(sequence-related amplified polymorphism)方法引入中华白海豚(Sousa chinensis)多态性研究中,利用高分辨率的毛细管凝胶电泳分析了模板DNA、Mg2+、dNTP、引物、Taq DNA聚合酶等因素对SRAP-PCR扩增结果的影响.确定了me1-em5为扩增中华白海豚基因组DNA的最佳引物对.并进一步确立了适合中华白海豚的SRAP最佳反应体系:25 mm3体系中,模板DNA浓度为0.8 ng/mm3,Mg2+浓度为1.0 mmol/dm3,dNTP浓度为0.1 mmol/dm3,引物浓度为0.2μmol/dm3,Taq DNA聚合酶浓度为0.04 U/mm3.利用该反应体系对10个白海豚样品进行SRAP分析的结果表明,不同样品间DNA谱带清晰、多态性丰富.证实该体系稳定可靠,可以用于中华白海豚的分子标记研究.  相似文献   

19.
The relationship between trophic position through delta13C and delta15N and trace metal concentrations (Zn, Cd, Cu and Hg) was investigated in the tissues of six marine mammal species from the Northeast Atlantic: striped dolphin Stenella coeruleoalba, common dolphin, Delphinus delphis, Atlantic white-sided dolphin Lagenorhynchus acutus, harbour porpoise Phocoena phocoena, white beaked-dolphin Lagenorhynchus albirostris, grey seal Halichoerus grypus stranded on French Channel and Irish coasts. White-beaked dolphins, harbour porpoises, white-sided dolphins, common and striped dolphins display the same relative and decreasing trophic position, as measured by delta15N values, along both the Irish and French channel coasts, reflecting conservative trophic habits between these two places. Hepatic and renal Cd concentrations were significantly correlated to muscle delta13C and delta15N values while Hg, Zn and Cu did not. These results suggest that Cd accumulation is partly linked to the diet while other factors such as age or body condition might explain Hg, Zn or Cu variability in marine mammals. Combined stable isotope and trace metal analyses appear to be useful tools for the study of marine mammal ecology.  相似文献   

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