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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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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
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INTRODUCTIONTheDenglouCape ,inthesouthwestoftheLeizhouPeninsula ,isatthenorthmarginoftropicalzone .SeveralresearchesandcartographiesoftheregionalgeomorphologyandQuater narygeology ,whichwerecarriedoutinthepast,allincludethisarea (MGL ,SCSIO ,CAS ,1 978;GPCSGRCZT… 相似文献
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运用光谱分析和GC-MS方法首次从卡氏豆荚软珊瑚Lobophytumcatelai中分离和鉴定出8个化合物:l,十六碳酸;2,异丁基十六碳酸酯;3,鲨肝醇;4十六酸丙酯;5,2,3一二羟基丙基十八酸酯;6,2β,3β-环氧基-5α-雄甾烷-17-醇;7,14-甲基-5α-胆甾-8-稀-3-酮;8,2α,3α一环氧基-5α-雄甾烷-17-醇。 相似文献
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Abstract. This paper describes the quantitative inventory of stony corals on a Maldivian reef after the bleaching event of 1998. The detailed data, collected in March 1999 and March 2000, comprise survival, new recruitment and regenerates. They were obtained in 6 transects laid out randomly on the reef flat, on 22 Acropora tables on 6 sites at the reef edge and on 39 Porites lobata blocks and 1 Diploastrea heliopora colony. The present cover of living zooxanthellate corals is reduced to ca. 2 – 5 % of its previous state. Acroporidae and Pocilloporidae were practically wiped out, while Poritidae survived partly and Agariciidae (esp. Pavona) are now the dominant group. New settlements on dead Acropora tables were mainly Agariciidae, followed by Acroporidae and Pocilloporidae. Regenerates on Porites were pronounced and the apparent yearly increase in mass was about threefold that of Diploastrea, which is 3 – 4 mm per year. The influence on reef ecology in terms of coral substrate and species, possible sources of larvae, change of guilds in reef builders, other species and the prospect for further development of the reef, with respect to growth versus erosion, is discussed. 相似文献
20.
Preparation of a New Geological Survey of Japan Geochemical Reference Material: Coral JCp-1 总被引:2,自引:0,他引:2
Takashi Okai Atsushi Suzuki Hodaka Kawahata Shigeru Terashima Noboru Imai 《Geostandards and Geoanalytical Research》2002,26(1):95-99
A new geochemical reference material, coral Porites sp. JCp-1 has been prepared by the Geological Survey of Japan (GSJ). Provisional values for twenty one major, minor and trace elements are presented. The homogeneity tests showed that all elements studied are considered to be homogeneously distributed. 相似文献