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11.
Coral Diseases in the Indo-Pacific: A First Record 总被引：3，自引：0，他引：3
Abstract. . The so-called "band" diseases of reef corals, the White Band Disease (WBD) and the Black Band Disease (BBD), were observed in the Red Sea and in the Philippines. Since they were previously known only from the western Atlantic, this is the first record for the Indo-Pacific region. WBD is neither infectious nor contagious and the pathogen is unknown. BBD is highly infectious and contagious and is caused by the cyanophyte Phormidium corallyticum. Susceptibility to WBD occurs throughout the order Scleractinia, but the effects of the disease are most severe among Acroporidae. Susceptibility to BBD seems to be restricted to Faviidae, with Platygyra and Goniastrea species the most heavily afflicted. WBD cannot be influenced by any parameter tested so far. BBD can be enhanced by light and by water eutrophication, and its advance can be stopped by antibiotics. An active WBD seems to be a precondition for the origin of BBD. 相似文献
12.
Five decades after a series of nuclear tests began, we provide evidence that 70% of the Bikini Atoll zooxanthellate coral assemblage is resilient to large-scale anthropogenic disturbance. Species composition in 2002 was assessed and compared to that seen prior to nuclear testing. A total of 183 scleractinian coral species was recorded, compared to 126 species recorded in the previous study (excluding synonomies, 148 including synonomies). We found that 42 coral species may be locally extinct at Bikini. Fourteen of these losses may be pseudo-losses due to inconsistent taxonomy between the two studies or insufficient sampling in the second study, however 28 species appear to represent genuine losses. Of these losses, 16 species are obligate lagoonal specialists and 12 have wider habitat compatibility. Twelve species are recorded from Bikini for the first time. We suggest the highly diverse Rongelap Atoll to the east of Bikini may have contributed larval propagules to facilitate the partial resilience of coral biodiversity in the absence of additional anthropogenic threats. 相似文献
13.
福建东山海域石珊瑚种类多样性及其空间分布 总被引：1，自引：0，他引：1
调查了福建东山珊瑚省级自然保护区内石珊瑚种类的多样性和群落的空间分布,共发现5种造礁石珊瑚,分别为标准蜂巢珊瑚（Faviaspeciosa）、锯齿刺星珊瑚（Cyphastrea serailia）、盾形陀螺珊瑚（Turbinaria peltata）、小星珊瑚（Leptastrea sp．）、角孔珊瑚（Goniopora sp．）,和1种非造礁石珊瑚猩红筒星珊瑚（Tubastrea coccinea Lesson）．结果表明：（1）东山石珊瑚优势种为标准蜂巢珊瑚、锯齿刺星珊瑚和盾形陀螺珊瑚,但是东山的造礁石珊瑚种类正在减少．（2）东山石珊瑚的空间分布呈现正态分布,受人类影响较小的中间区域珊瑚覆盖率最高,受人类活动影响大的两端区域没有或者只有极少量的珊瑚分布．（3）东山湾内理化环境退化明显,部分区域已经不太适合珊瑚生长,仅仅少数站位分布少量石珊瑚群落,而大部分站位已经不见石珊瑚的踪影．随着远离东山湾方向,珊瑚覆盖率显著增加,在头屿一赤屿区域珊瑚覆盖率达到最大,珊瑚生长状态较好,具有较高的保护价值．随着离澳角渔港码头距离越来越近,珊瑚的覆盖率则逐渐降低．针对东山珊瑚分布区域的环境现状,应该加强东山湾污水入海的控制,合理开展海水养殖,开发利用与环境保护并重,这才能保护处在东山湾外的珊瑚群落． 相似文献
14.
Zvuloni A Mokady O Al-Zibdah M Bernardi G Gaines SD Abelson A 《Marine pollution bulletin》2008,56(3):430-438
Coastal marine reserves in general, and coral reef reserves in particular, are typically composed of scattered patches separated by uninhabited areas. Due to the sessile mode of life of adult corals, larval connectivity is often the only agent of gene flow between reef localities. In this study we examined the connectivity between populations of the common scleratinian coral Stylophora pistillata at the northern tip of the Gulf of Aqaba (Red Sea), using the rDNA ITS (internal transcribed spacer) as a molecular marker. Sequence comparisons among recruits indicated very similar, equally-diverse, assemblages of recruits in both the northern (highly affected by anthropogenic disturbances) and southern (less affected) study sites, implying a high larval connectivity or common sources of larval supply. By contrast, sequence diversity observed among adults declined sharply from southern to northern sites, accompanied by genetic differentiation of the respective populations. Based on Fu's Fs-test of selective neutrality, it may be suggested that various post-settlement selective regimes, presumably more intense in the northern sites, provide a reasonable explanation for the observed patterns of genetic diversity. The suggested hypothesis is supported by the sharper decline in sequence diversity found between recruits and adults in the northern sites. This study exemplifies the necessity to consider local selective factors, in addition to larval connectivity, when managing marine reserves. 相似文献
15.
In contrast to the purely crystalline model of the coral fibre, a transversal zonation is made visible within fibres by specific
preparations (enzymatic or light acidic etchings). This growth zonation that corresponds to the successive positions of the
secretory ectoderm during septal development shows that crystallization of coral fibre is controlled not only by an external
organic coating of fibres, but also includes intra-fibrous organic components. This results in a micron-scaled internal structure
of fibres, with a noticeable diversity depending on species. In parallel, soluble matrices also exhibit significant differences,
although the global high content in acidic amino acids is always observed. Gathering these two sets of data allows the current
ideas concerning structures and growth modalities of coral septa to be discussed. Basically, the respective role of centres
of calcification and fibres during septal development appears clearly different from the current ideas, resulting in significant
change in interpretation of coral structures, with concerns in both skeleton formation and understanding of diagenetic processes.
Received: 2 November 1998 / Accepted: 10 May 1999 相似文献
16.
The benthic fauna on reefs around the Glorieuses Islands, a small and protected Indian Ocean archipelago northwest of Madagascar, was surveyed in November 2015, focusing particularly on the orders Alcyonacea (soft corals and gorgonians) and Scleractinia (stony corals). The species richness of both groups was rather low for a protected, relatively pristine environment in the region. Though certain soft ‘fugitive’ alcyonacean species were noticeably abundant, other soft corals were rare. Sediment-tolerant faviid corals were abundant among the scleractinians. The sediment around the reefs was fine-grained and white, and appeared to be derived from abundant green macroalgae Halimeda and coralline seaweeds. The abundance of these, in turn, might have been attributable to nutrient enrichment from guano deposited on one of the islands by migratory seabirds, causing the aforementioned anomalies in coral biodiversity and abundance. 相似文献
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18.
石珊瑚目是中新生代的重要造礁生物。直到中三叠世才大量出现多种石珊瑚化石,距二叠纪末生物大灭绝、古生代皱壁珊瑚和床板珊瑚灭亡14 Ma之久。石珊瑚的起源和早期系统发育,成为生物大灭绝及复苏的一个难题。文章目的是综述多学科研究石珊瑚早期系统发育的进展,以及多家系统分类,展望前景。研究方法有骨骼构造与微细构造及软体的对比,时空分布分析,寻找早期珊瑚化石及分子生物学等。研究结果主要有石珊瑚可能起源于只有软体的海葵类,发现早期石珊瑚化石,以及石珊瑚在300 Ma之前已演化为两支,但还有不少空白和争议。结论是为了查明石珊瑚的早期系统演化和分类,需要加强古生物与今生物学者多学科交叉的综合研究,努力寻找中间环节,填补研究空白。 相似文献