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141.
Based on literature and survery data of fish composition collected by bottom trawl investigation from 2006 to 2007 infour main estuaries of China southeastern coastal areas and their adjacent waters,changes of the taxonomic diversity across spatialand temporal scales of fish community were analyzed by taxonomic diversity indices.The results are as follows:a total number of1397 fish species(including some freshwater species),belonging to 2 classes,42 orders,186 families and 593 genera,were collected inthe studied sea areas.The species richness increased with lower latitudes,particularly so with Perciformes.There were 339 fish spe-cies in the Yangtze River Estuary and adjacent waters,belonging to 2 classes,31 orders,101 families and 231 genera.There were 535fish species in the Minjiang River Estuary and adjacent waters,belonging to 2 classes,33 orders,133 families and 323 genera.A totalnumber of 803 fish species were collected in the Jiulongjiang River Estuary and adjacent waters,which belonged to 2 classes,35 orders,155 families and 419 genera.And 1021 fish species which belonged to 2 classes,32 orders,153 families,and 466 genera were collectedin the Pearl River Estuary and adjacent waters.The numbers of orders and families of fish species from the northern to the southern wa-ters first increased and then decreased.The average variation in taxonomic distinctness(Λ+)gradually decreased with lower latitudes inthe four estuaries and adjacent waters.There were no significant differences in the average taxonomic distinctness(△+)among the fourestuaries and adjacent waters,and fish fauna were closely related with each other,and all of them belonged to the same zoogeographicalfauna(Indian-Malaysia fauna).Fish composition in the Minjiang River Estuary and adjacent waters was more similar to that in the Jiu-longjiang River Estuary and adjacent waters among the four estuaries.Compared with the historical data,the average taxonomic dis-tinctness of fish community showed a great decrease in the Minjiang River Estuary and the Jiulongjiang River Estuary and their adjacentwaters.  相似文献   
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海洋鱼类分子系统地理学研究进展   总被引:1,自引:0,他引:1  
简要叙述了分子系统地理学的发展简史、研究内容,重点介绍了Avise的5种物种分布模式及中性溯祖理论。并回顾了近年来分子系统地理学的研究进展及其在海洋鱼类研究中的应用,最后对海洋鱼类分子系统地理学研究进行了展望。  相似文献   
144.
Palaeozoic and early Mesozoic fish faunas of the Japanese Islands   总被引:2,自引:0,他引:2  
MASATOSHI GOTO 《Island Arc》1994,3(4):247-254
Abstract In recent years, many fish teeth and scales have been found from the Palaeozoic and Mesozoic age strata of the Japanese Islands. This study is a compilation of the Japanese fish record from the Palaeozoic and early Mesozoic age deposits. Based on the published and unpublished data, the fossil fishes from the Palaeozoic and Early Mesozoic of Japan can be classified into 27 genera and 33 species, that is, one species of Devonian placoderms, 19 species of Permian to Jurassic elasmobranchs, three species of Permian cochliodonts, seven species of Carboniferous to Permian petalodonts, and three species of Triassic to Jurassic osteichthyans.  相似文献   
145.
本文通过笔者实际考察资料及国内外学者研究资料,综合分析了叠层石与沉积矿产关系的研究现状,探讨了叠层石和造叠层石底栖微生物群落对铁、铜、多金属、磷、锰等矿产的成矿作用。叠层石可以溉括为直接的和间接的两种成矿作用:①叠层石为容矿体,其本身就是一种矿石类型;②叠层石不含矿,其岩礁为矿的间隔体。后者是一种金属硫化物避开叠层石岩礁而在礁侧沉积成巨大的富矿模式。  相似文献   
146.
广东大亚湾石珊瑚群落的分布及动态变化   总被引:2,自引:0,他引:2  
2006年6月对位于南海北部亚热带的大亚湾和大鹏湾石珊瑚群落的分布、种类和覆盖率进行了调查,结果显示大亚湾共有石珊瑚24种,以秘密角蜂巢珊瑚(Favites abdita)为优势种,总覆盖率为20%,大鹏湾有石珊瑚21种,以精巧扁脑珊瑚(Platygyra daedalea)为优势种,总覆盖率为7.9%。大亚湾石珊瑚群落健康状况良好,但生长稀疏,群落密度低,空间结构简单,生长带窄;与1964年、1983年、1984年和1991年的调查结果相比,覆盖率从76.6%下降到20%,优势种从枝状的霜鹿角珊瑚(Acropora Pruinosa)转变成块状或皮壳状的秘密角蜂巢珊瑚,群落生态退化严重,主要原因可能是人为破坏活动对珊瑚本身以及生长环境造成的压力所致,包括过度捕捞、盗采珊瑚、沿岸施工和水体污染等,建议采取相应的保护措施。  相似文献   
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Michael Feige 《GeoJournal》2001,53(3):323-333
Kiryat-Arba and Jewish Hebron are communities planted in the most heated front of the Israeli-Palestinian conflict. This paper examines how the Hebron Jewish settlers' collective memory interprets the `truth' of Hebron as a typical Israeli Place that reveals Zionism in its purest form. Today the populations of Kiryat-Arba and of the Hebron Jewish enclaves number about 5,000 and 500, respectively. Kiryat-Arba functions as an economic and educational centre for the nearby Jewish settlements in the region. Rejecting the segregative concept of a separate Jewish settlement overlooking Hebron, the settlers treat Kiryat-Arba as part of Hebron. Some 70,000 Palestinians live in Hebron, many more residing in neighbouring towns and villages, cutting Hebron – Kiryat–Arba off from the nearest Jewish urban centres of Jerusalem and Beer-Sheva. The settlers initiated the narrative of `Return' to the city after the massacre of Jews in 1929 in the city, as the key symbol Symbolically, the first place Hebron Jews reidentified with was its ancient Jewish graveyard. Today, IDF soldiers protect settlers and their visitors who want to tour Hebron. The huge gulf between `metaphorical Hebron' as a symbolic centre and `actual Hebron' as a poor development town creates tensions fuelling violent events. The Jews in Hebron take the Israeli logic of `Place' making to its extreme, thus testing concepts of Israeli territoriality. If Israeli society rejects Hebron as a `Place' constructed from intense memories and violent national encounters, it would leave the Hebron Jews out of the so-called Israeli normalcy.  相似文献   
150.
198 7年 1 1月至 1 988年 4月在菲尔德斯半岛东南附近海域采集到的仔鱼体长为 1 3 .1 -1 5 mm,它们都处于早期发育阶段。经鉴定隶属一科 (南极鳕鱼科 Nototheniidae) ,一属 (Notothe-nia)两种 :(N.larseni Lonnb,N.gibberifrons Lonnb)。 N.larseni占 88 ,N.gibberifrons占1 2 %。本文对仔鱼形态作了详细的描述。  相似文献   
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