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11.
中华白海豚(Sousa chinensis)组织中多氯联苯的研究   总被引:1,自引:0,他引:1  
以珠江口海域的两头中华白海豚为研究对象,采用气相色谱法分析了海豚组织中多氯联苯(PCBs)的含量分布特征和毒性水平。结果表明,PCBs在海豚10种不同组织中的含量范围为25.1—85567.3ng/g,PCBs含量最高的组织为额隆和皮肤,其次为肝脏、肌肉、心脏、睾丸和脑,最低的为肺、胃和肾脏;PCBs同系物和同族物在海豚不同组织中的分布特征相似,同系物中以PCB101+113和PCB153所占总量的百分比最大,在10.25%-51.70%之间;在同族物中以含在同族物中以5个氯原子和6个氯原子的PCBs为主,所占百分比均在23.53%-60.06%之间;运用二蛞哄毒性当量(TEQ)评价了中华白海豚不同组织中PCBs的毒性,其TEQs范围为55.9—68191.0pg/g,其中皮肤TEQs含量最高。TEQs主要来自非邻位取代的PCBs,占总量的74.15%-99.62%,其中来自PCB126的占34.11%-96.5I%。与世界其他海域海豚的PCBs污染水平相比,成年中华白海豚受PCBs污染严重,其体内的PCBs含量和毒性当量均已超出安全浓度范围,对其健康已造成威胁。  相似文献   
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Photo‐identification has been established as a helpful tool in cetacean research. However, no study to date has attempted to apply this method to short‐beaked common dolphins (Delphinus delphis L.). We present here the results of two studies that were conducted concurrently in Mercury Bay and the Hauraki Gulf on the north‐east coast of New Zealand's North Island. Methods for distinguishing between individual dolphins are discussed. Sighting records of recognisable individuals indicate that some common dolphins move between Mercury Bay and the Hauraki Gulf (100 km distance), as well as between Mercury Bay and Whakatane (200 km distance). Common dolphin abundance and site fidelity appeared to be greater in the Hauraki Gulf than in Mercury Bay. A selection of photographs of distinct individuals is presented to allow future studies to compare their sighting records to ours, which may help establish the extent of home ranges, site fidelity, and possibly even longevity for common dolphins.  相似文献   
14.
Parties to the convention on international trade in endangered species of wild fauna and flora (CITES) can export specimens if the exporting party issues a non-detriment finding (NDF), stating that removals will not harm wild populations. NDFs are supposed to be based on science. This article discusses the issuance, and acceptance, of non-detriment findings despite concerns expressed by experts and a lack of scientific data, using a controversial trade of dolphins as a case study. In early 2003, at least 94 Indo-Pacific bottlenose dolphins (Tursiops aduncus) were captured in the coastal waters of Solomon Islands. Bottlenose dolphins are listed on CITES Appendix II and as such require an NDF for their export. The IUCN Cetacean Specialist Group advised against this proposed export, stating that it knew of no published population assessments or other research upon which a valid NDF could be based. Despite this, in July 2003, 28 dolphins were exported to Mexico. A second controversial export occurred on 18 October 2007, when 28 dolphins were exported from Solomon Islands to the United Arab Emirates, an export regarding which IUCN experts again expressed concerns. Two additional exports, of 18 dolphins total, went to the Philippines in 2008.  相似文献   
15.
总结了北京海洋馆对2003年3月20日从日本购进的6条海豚在隔离期间所采取的医疗保健措施。针对隔离期内6条海豚表现出的厌食、消瘦、贫血、肠炎、便秘等症状,分别采取了驱虫、补充维生素、处理外伤、补液等保健和医疗措施。6条海豚身体恢复健康,已顺利度过隔离期。这一系列医疗保健措施的制定,充分考虑了北京海洋馆的实际情况,同时汲取了国内外该领域的经验,相信可为国内外同行提供有益的帮助。  相似文献   
16.
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   
17.
The fatty acid composition of the blubber of five dusky dolphins Lagenorhynchus obscurus and five Cape fur seals Arctocephalus pusillus pusillus from the northern Benguela ecosystem (South-East Atlantic) and their main prey was determined. Differences in fatty acid composition of the inner and outer blubber layer of the dolphins were substantial, with higher relative amounts of monoenic fatty acids with 14, 16 and 18 carbons in the outer layer and higher relative amounts of saturated, long-chain monounsaturated and polyunsaturated fatty acids in the inner layer. This stratification is similar to the general pattern that has been observed in a variety of marine mammals, but the degree of stratification is the highest yet observed, with the long-chained (n3) fatty acids being more than 20 times more abundant in the inner than in the outer layer. On the other hand, the seals’ blubber consisted of only one uniform layer, densely supported by connective tissue. The whole-body fatty acid composition of the prey was species specific. The dolphins and seals had significantly different fatty acid composition of their blubber. In both species, the blubber fatty acid composition was different from the composition of the prey, indicating that a phylogenetic component is involved in the determination of the fatty acid composition of the blubber.  相似文献   
18.
The underwater acoustic noise of five representative whale-watching boats used in the waters of west Maui was measured in order to study the effects of boat noise on humpback whales. The first set of measurements were performed on 9 and 10 March, close to the peak of the whale season. The ambient noise was relatively high with the major contribution from many chorusing humpback whales. Measurements of boat sounds were contaminated by this high ambient background noise. A second set of measurements was performed on 28 and 29 April, towards the end of the humpback whale season. In both sets of measurements, two of the boats were inflatables with outboard engines, two were larger coastal boats with twin inboard diesel engines and the fifth was a small water plane area twin hull (SWATH) ship with inter-island cruise capabilities. The inflatable boats with outboard engines produced very complex sounds with many bands of tonal-like components. The boats with inboard engines produced less intense sounds with fewer tonal bands. One-third octave band measurements of ambient noise measured on 9 March indicated a maximum sound pressure level of about 123 dB re 1 microPa at 315 Hz. The maximum sound pressure level of 127 dB at 315 Hz was measured for the SWATH ship. One of the boats with outboard engines produced sounds between 2 and 4 kHz that were about 8-10 dB greater than the level of background humpback whale sounds at the peak of the whale season. We concluded that it is unlikely that the levels of sounds produced by the boats in our study would have any grave effects on the auditory system of humpback whales.  相似文献   
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