The Black Band Disease of Atlantic Reef Corals.   总被引：4，自引：0，他引：4  

Klaus  Rutzler  Deborah L.  Santavy Arnfried  Antonius 《Marine Ecology》1983,4(4):329-358

Abstract. The cyanophyte (Cyanobaclerium) that causes black band disease of Atlantic reef corals is described under the name Phormidium corallyticum , new species (family Oscillatoriaceae) , and its generic placement is discussed from the standpoint of the GEITLERian (classical) and D rouet systems. Distinguishing characters include densely interwoven filaments that form a blackish mat and trichomes without significant cell wall constrictions, almost isodiametric cells (4.2 μm mean width, 4.0μm mean length) tapering end cells, and thin (0.1 μm or less) mucilaginous wall coating. Transmission electron microscopy shows typical cyanophyte cell walls, sheath, nucleoplasm, and cytoplasmic inclusions, but an unusual thylakoid of straight, and, as seen in cell cross section, radiating lamellae. The dark coloration is due to a high concentration of phycocyanin and some phycoerythrin. The species is similar to Oscillatoria (= Phormidium) submembranacea , which differs in several morphological features and does not infect coral tissue. It is concluded that Phormidium should be used for this and related species that have external mucilage but not the distinct sheath found in Lyngbya.  相似文献   

The Structure of Coral Communities at Hurghada in the Northern Red Sea   总被引：1，自引：0，他引：1  

Bernhard  Riegl Branko  Velimirov 《Marine Ecology》1994,15(3-4):213-231

Abstract. The community structure of hard and soft corals, with an emphasis on hard corals, was determined by means of line-transects on 9 on-and off-shore reefs of different type and different wave exposure in the Northern Red Sea near Hurghada in Egypt. Coral communities were found to differentiate along a horizontal wind- and wave-exposure gradient. Exposed communities were dominated by Acropora species, sheltered communities by Porites species, and semi-exposed communities by Millepora species. Also, vertical within-reef zonations following a depth gradient were observed; these were unique for each exposure-determined community type. Average transect diversity was highest on semi-exposed reefs, lowest on sheltered reefs. Reef slopes were more diverse than other reef zones. The observed community structure was compared with data from the literature, and widely distributed, roughly comparable hard and soft coral communities were identified.  相似文献   

Coral Cover Change Associated to El Niño, Eastern Pacific, Costa Rica, 1992–2001     

Carlos E. Jiménez  & Jorge Cortés 《Marine Ecology》2003,24(3):179-192

Abstract. Changes in live and dead coral cover were documented at three localities off the Costa Rican central Pacific coast first in 1992 during the aftermath of the 1991–1992 El Niño; again in the period between 1994 and 1995, and last in January 2001. Recovery of coral communities after the 1991–1992 El Niño was expressed by a significant increase (～40 %) in 1994 of live coral cover at one locality (Manuel Antonio). A subsequent decrease (～50 %) in response to the very strong 1997–1998 episode was recorded at Manuel Antonio and Ballena, mainly due to partial tissue mortality of branching (Pocillopora spp.) and massive (Porites lobata) corals. Mortality of entire colonies associated to that event was scarce and confined to branching and nodular (Psammocora stellata) corals. This species was not found at one locality (Cambutal) in the 2001 survey and it is presumed locally extinct. The recovery of this coral and others will depend on recruits from surviving colonies in deeper waters and other coral communities in the vicinity. Within sites at a given locality, contrasting results in live coral cover variability were found. This is partially due to distinct coral assemblages, coral growth, physical exposure to tidal regime, and, related to the latter, variable duration and intensity of the warming event. In general, predominant meteorological conditions at the studied area are conducive to solar radiation (UV) stress during El Niño years and are related to changes in the atmosphere‐ocean interactions in response to the warming events.  相似文献   

Impact of repetitive thermal anomalies on survival and development of mass reef‐building corals in the Maldives          下载免费PDF全文

Konstantin S. Tkachenko 《Marine Ecology》2015,36(3):292-304

The distribution of dominant coral genera and their response to the recent sea temperature anomalies in the last three decades are analyzed across reefs of the Maldivian Archipelago, which spans 860 × 120 km in the central Indian Ocean. The Maldives suffered one of the worst coral mortality rates in the Indian Ocean in the 1998 warming event and experienced two sub‐lethal thermal anomalies in 2003 and 2010. The results showed that the Acropora proved an important driver of post‐1998 recovery and has become a major dominant genus in most Maldivian reefs at present. The average coral cover and proportion of acroporids have decreased from south to north and represent correspondently 70.6/59% for the southern atoll, 62/53% for the central atoll and 33/10.3% for the northernmost atoll. Stylophora, Seriatopora and the hydrocoral Millepora were not found and are considered candidates for local extirpation from the Maldives. Higher thermal variability and frequency of thermal stress might lead to the decrease in the abundance of susceptible taxa in the northernmost atoll. No phase‐shift to algae‐dominated reefs was observed in any of the three locations. Factors contributing to coral recovery and acclimatization are discussed.  相似文献   

High inorganic phosphate concentration in coral mucus and its utilization by heterotrophic bacteria in a Malaysian coral reef          下载免费PDF全文

Ryota Nakajima  Yasuaki Tanaka  Teruaki Yoshida  Tamami Fujisawa  Asami Nakayama  Yumi Fuchinoue  Bin Haji Ross Othman  Tatsuki Toda 《Marine Ecology》2015,36(3):835-841

Inorganic nutrient contents of mucus released by Acropora corals and its utilization by heterotrophic bacteria at several different hour intervals in the coral mucus were investigated at a coral reef in Malaysia. The dissolved inorganic phosphate (DIP) concentration was 135‐fold higher than in the ambient seawater, probably due to inorganic P release from the coral gut cavity. We experimentally confirmed that heterotrophic bacteria rapidly (within 8 h) consumed ca. 80% of the initial concentration of DIP derived from coral mucus. High DIP concentration in coral mucus may enhance heterotrophic bacterial production and associated carbon flow in the microbial loop of reef ecosystems.  相似文献   

Analysis of multiple enteric viral targets as sewage markers in coral reefs     

Lipp EK  Futch JC  Griffin DW 《Marine pollution bulletin》2007,54(12):1897-1902

Water and coral mucus samples were collected from throughout the Florida Keys National Marine Sanctuary and the Dry Tortugas for three years and were analyzed for human enteric viruses (enteroviruses, noroviruses, hepatitis A virus and adenoviruses) as conservative markers of human sewage using molecular methods. Of the 100 coral and water samples collected, 40 contained genetic material from one or more human enteric viruses. DNA-based adenoviruses were detected widely, in 37.8% of samples and at 91% of stations, including ‘pristine’ reefs in the Dry Tortugas; however, the detection rate was 12% for the RNA-based enteroviruses and noroviruses (hepatitis A virus was never detected). The disparity between the prevalence of RNA- and DNA-based viruses suggests the need for additional work to determine the utility of adenovirus as marker of human sewage.  相似文献   

Benthic status of near-shore fishing grounds in the central Philippines and associated seahorse densities     

Marcus JE  Samoilys MA  Meeuwig JJ  Villongco ZA  Vincent AC 《Marine pollution bulletin》2007,54(9):1483-1494

Benthic status of 28 near-shore, artisanal, coral reef fishing grounds in the central Philippines was assessed (2000-2002) together with surveys of the seahorse, Hippocampus comes. Our measures of benthic quality and seahorse densities reveal some of the most degraded coral reefs in the world. Abiotic structure dominated the fishing grounds: 69% of the benthos comprised rubble (32%), sand/silt (28%) and dead coral (9%). Predominant biotic structure included live coral (12%) and Sargassum (11%). Rubble cover increased with increasing distance from municipal enforcement centers and coincided with substantial blast fishing in this region of the Philippines. Over 2 years, we measured a significant decrease in benthic 'heterogeneity' and a 16% increase in rubble cover. Poor benthic quality was concomitant with extremely low seahorse densities (524 fish per km(2)). Spatial management, such as marine reserves, may help to minimize habitat damage and to rebuild depleted populations of seahorses and other reef fauna.  相似文献   

藏北羌塘中央隆起带果干加年山晚三叠世珊瑚化石发现及其地质意义   总被引：3，自引：0，他引：3  

纪占胜  姚建新  武桂春 《地质学报》2010,84(8):1095-1104

藏北羌塘盆地中央隆起带果干加年山北坡首次发现了较丰富的珊瑚化石。珊瑚主要属种有8属10种及未定种:Distichophyllia norica(Frech),Gablonzeria irregularis DengZhang,Margarophyllia stylophylloides(Vinassa deRegny),M.zogangensisDengZhang,Margarophyllia? sp.,Montlivaltia tenuise DengZhang,Pamiroserisrectilamellosa(Winkler),Paradistichophyllum verticalis DengZhang,Paradistichophyllum?sp.,StylophyllopsismosjvariFrech等。产出这些珊瑚化石的灰岩地层原来被认为是混杂在晚三叠世望湖岭组碎屑岩中的古生代灰岩断块,而新发现的珊瑚指示地层时代并非是古生代,而是晚三叠世。这说明果干加年山地区不存在上三叠统碎屑岩和古生界灰岩混杂的现象。果干加年山地区的晚三叠世沉积不仅包含有望湖岭组的碎屑岩,还包含有夹在碎屑岩之间的浅海相灰岩。本次研究和前人的资料表明羌塘中央隆起带在晚三叠世并非是隆起剥蚀区,而是海洋沉积区。因而,以往建立在中央隆起带为隆起剥蚀区认识基础上的羌塘盆地晚三叠世沉积古地理环境和"一隆两坳"的大地构造格局认识需要重新考虑。  相似文献   

南沙群岛永暑礁第四系研究   总被引：1，自引：1，他引：1  

赵焕庭  沙庆安 《热带地理》1994,14(2):97-104

水暑礁礁坪的“南水１井”井尺１５２．０７ｍ，采用了古生物与古地磁定年，＾１４Ｃ、氨基酸外消旋、铀系和ＥＳＲ等方法测年，确定该井地层属第四系，全新统与更新统的分界在井深１７．３ｍ，上更新统与中更新统的分界难确定，中更新统与下更新统分界在９０ｍ。永暑礁第四第划分为全新统南海组，０－１７．３ｍ，更新统南沙组，１７．３－１５２．０７ｍ（末到底）。  相似文献   

Impact of elevated ammonium on reproduction in two Hawaiian scleractinian corals with different life history patterns     

Cox EF  Ward S 《Marine pollution bulletin》2002,44(11):1230-1235

Elevated nutrients have the potential to disrupt reproduction in scleractinian corals, with consequent impacts on population dynamics. Reproduction in broadcast spawning (Montipora capitata) and brooding (Pocillopora damicornis) species was assessed following exposure to elevated ammonium in a microcosm experiment. Planulation in P. damicornis ceased following 4 months of ammonium exposure and did not recover until 3 months after termination of nutrient enrichment. Larval settlement and survivorship were not affected by ammonium enrichment. Few significant changes were found for reproductive parameters of M. capitata. There was a significant but small decrease in egg size (430 microm in control eggs to 408 microm in eggs from ammonium enrichment treatments), but no differences in total fecundity or fertilization success. This may be related to the presence of zooxanthellae in the eggs of M. capitata, in contrast to changes in reproduction previously reported in Acropora species, whose eggs do not contain zooxanthellae.  相似文献