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Abstract. Survival and behaviour of the hermatypic coral Diploria strigosa was studied during 6–24 h doses with water-accomodated fractions of chemically dispersed crude oil, and for a subsequent recovery period of 1 month. Experiments utilized a flow-through laboratory dosing procedure and incorporated petroleum hydrocarbon measurements in order to simulate a major but short-term oil spill in shallow subtidal benthic reef environments. Chemically dispersed oil treatments consisted of Arabian Light Crude oil with Corexit 9527 or BP1100WD at 1–20 ppm concentrations of oil.
In general, effects observed were sub-lethal, temporary, and associated with the highest concentrations tested. Responses to the presence of dispersed oil at 20ppm for 24 h included mesenterial filament extrusion, extreme tissue contraction, tentacle retraction and localized tissue rupture. The nature and severity of reactions during the dosing phase varied between colonies and treatments, but colonies typically resumed normal behaviour within 2 h to 4 d of the recovery period. It therefore seems unlikely that observed biological effects would impair long-term viability. 相似文献
In general, effects observed were sub-lethal, temporary, and associated with the highest concentrations tested. Responses to the presence of dispersed oil at 20ppm for 24 h included mesenterial filament extrusion, extreme tissue contraction, tentacle retraction and localized tissue rupture. The nature and severity of reactions during the dosing phase varied between colonies and treatments, but colonies typically resumed normal behaviour within 2 h to 4 d of the recovery period. It therefore seems unlikely that observed biological effects would impair long-term viability. 相似文献
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The Role of Isopod Crustaceans in the Reef Crest Community at Carrie Bow Cay, Belize 总被引:1,自引:0,他引:1
Abstract. The species composition and numbers of specimens of isopod crustaceans from the rubble of a Belizean reef crest were obtained. Four sets of 30 samples were taken from three rubble zones (rubble with algal turf, rubble between Thalassia plants, and pure rubble), in four different collecting periods. Twenty-four species of isopods were identified, sexed and counted. By means of a Likelihood Ratio Chi-square Contingency Table Analysis the presence of 13 species was shown to be positively correlated with habitat, 15 species with season, and nine species with habitat and season combined. From the spread of total numbers and of ovigerous females it is proposed that the isopods may be grouped into three patterns: a) those present and breeding in the reef crest rubble throughout the year, i. e. stress-tolerant species; b) those showing a breeding peak in summer and a population decrease in winter-spring, i. e. opportunist species; and c) those showing a breeding peak in the fall, and a second peak in spring, and a decrease or complete avoidance of the habitat, especially by ovigerous females, in the summer. The diversity of the Belizean reef crest isopod fauna is compared with the published report of the isopod fauna of a coral reef in Madagascar. Several similarities in composition are noted. The multiplicity of microhabitats is invoked as a possible explanation for the relatively high diversity of anthuridean isopods in coral reefs. 相似文献
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涠洲岛珊瑚礁生态系中浮游动植物与环境因子关系的初步探讨 总被引:2,自引:0,他引:2
本文根据1990年4月、10月间的理化分析数据,结合2002年9月涠洲岛珊瑚礁生态环境的调查状况,首次从珊瑚礁生态系的角度初步探讨该岛区浮游动植物与环境因子的关系。结果表明:该岛区浮游动植物的分布具有明显的区域性和季节性,既体现了珊瑚礁生态系具有较高的初级生产力特征,也体现了浮游动植物具有显著的季节交替现象。相关分析显示,水温、盐度、N,P,Si营养盐对浮游植物的种类组成及数量变动均有明显影响,但对浮游动物的影响不大;N是该生态系中浮游植物的限制因子,P限制状况只有在珊瑚礁生长带较深的海域出现,Si呈相对富足状态。 相似文献
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1 .IntroductionInthe whole service period of the platforms ,some damage is unavoidable due to the corrosion,impact ,fatigue and so on.The damage whould cause the structures’ultimate capacity and safety de-crease .Presently,it is generally acceptedthat the detection of damage involes considerable statisticaluncertainties,thus lot of efforts is made for the damage probalility model ,for example Song and Lu(1996) usedthefuzzy-settheoryto estimatethe humanerrorsthroughthe definitionof inspection… 相似文献
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David K. A. Barnes 《Marine Ecology》2001,22(3):189-200
Abstract. The reef‐dwelling oyster Dendrostrea frons occupied only a small proportion of space in coral reefs of the Quirimba Archipelago, Mozambique, but supported a disproportionately high variety of taxa. Assemblages on primary (substratum), secondary (dead coral heads) and ephemeral secondary space (D. frons shells) of similar area were compared across 5 depths (5, 10, 15, 20 and 25 m) and at four taxonomic levels (species, genus, class and phylum). Differences between the taxonomic richness of each type of space differed with both taxonomic level considered and depth. Of the three categories of space considered, ephemeral secondary space had the most taxa at all levels with the maximum at 10 – 15 m. Despite being small in space and time, animal externa, such as shells of D. frons, may provide important niches for particular organisms at many taxonomic levels. 相似文献
39.
西沙礁序列的磁性地层学研究 总被引:3,自引:0,他引:3
利用西沙群岛西琛一井330m以上井段的149块岩心标本,用美国2-G型超导磁力仪进行了古地磁测定,获得了一个从更新世至中新世晚期包括布容,松山,高斯和吉尔伯特四个极性时及若干亚极性的磁性地层柱,为礁序列的划分对比,提供了新的依据。 相似文献
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Risk Assessment for Tuzla Naval Base Breakwater 总被引:5,自引:0,他引:5
Can Elmar BALAS 《中国海洋工程》2003,17(3)
1 .IntroductionTurkeywasstruckbytwomajorearthquakeeventsonAugust 1 7thandNovember 1 2th ,1 999,namedIzmit (Mw=7.4 )andD櫣zce (Mw=7.2 )earthquakes,respectively .ThestationsoperatedbytheGeneralDirectorateofDisasterAffairs,theKandilliObservatoryandEarthquakeResearchInstituteofIstanbulTechnicalUniversitymeasuredatleast 2 7stronggroundmotionsfortheIzmitearthquakewithin 2 0 0kmofthefault.AsignificantsegmentofthefaultrupturedintheareabetweenthewestofGolcukandtheeastofLakeSapanca .Inthesou… 相似文献