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1.
Portfr JW 《Science (New York, N.Y.)》1974,186(4163):543-545
Competition for space amon reef corals includes interspecific destruction by extracoelenteric digestion., rapid growth. and Overtopping. No Caribbean species excela in all strategies, and on western Caribbean coral reefs there is a positive correlation between coral abudance and diversity. On eastern Pacific coral reefs, however. Pocillopora damicornis excludes other corals, and on these reefs there is an inverse relation between coral abundance and diversity, except in areas where distrubances, such as Acanthaster predation offset space monopolization. 相似文献
2.
Wilkinson CR 《Science (New York, N.Y.)》1987,236(4809):1654-1657
Sponges consume an order of magnitude more organic matter on Caribbean coral reefs than on the Great Barrier Reef. This rate of consumption is attributed to Caribbean sponge biomass being five to six times greater than that on the Great Barrier Reef, on average, and to the absence in the Caribbean of phototrophic sponges, which are a feature of clean water regions of the Great Barrier Reef. The long temporal and spatial separation of the Atlantic and Pacific oceans has resulted in the evolution of dissimilar sponge faunas, with Caribbean sponges being heterotrophic, whereas many Great Barrier Reef sponges rely on nutritional input from photosynthetic symbionts. 相似文献
3.
Mumby PJ Dahlgren CP Harborne AR Kappel CV Micheli F Brumbaugh DR Holmes KE Mendes JM Broad K Sanchirico JN Buch K Box S Stoffle RW Gill AB 《Science (New York, N.Y.)》2006,311(5757):98-101
Since the mass mortality of the urchin Diadema antillarum in 1983, parrotfishes have become the dominant grazer on Caribbean reefs. The grazing capacity of these fishes could be impaired if marine reserves achieve their long-term goal of restoring large consumers, several of which prey on parrotfishes. Here we compare the negative impacts of enhanced predation with the positive impacts of reduced fishing mortality on parrotfishes inside reserves. Because large-bodied parrotfishes escape the risk of predation from a large piscivore (the Nassau grouper), the predation effect reduced grazing by only 4 to 8%. This impact was overwhelmed by the increase in density of large parrotfishes, resulting in a net doubling of grazing. Increased grazing caused a fourfold reduction in the cover of macroalgae, which, because they are the principal competitors of corals, highlights the potential importance of reserves for coral reef resilience. 相似文献
4.
Climate change,human impacts,and the resilience of coral reefs 总被引：11，自引：0，他引：11
Hughes TP Baird AH Bellwood DR Card M Connolly SR Folke C Grosberg R Hoegh-Guldberg O Jackson JB Kleypas J Lough JM Marshall P Nyström M Palumbi SR Pandolfi JM Rosen B Roughgarden J 《Science (New York, N.Y.)》2003,301(5635):929-933
The diversity, frequency, and scale of human impacts on coral reefs are increasing to the extent that reefs are threatened globally. Projected increases in carbon dioxide and temperature over the next 50 years exceed the conditions under which coral reefs have flourished over the past half-million years. However, reefs will change rather than disappear entirely, with some species already showing far greater tolerance to climate change and coral bleaching than others. International integration of management strategies that support reef resilience need to be vigorously implemented, and complemented by strong policy decisions to reduce the rate of global warming. 相似文献
5.
Meylan A 《Science (New York, N.Y.)》1988,239(4838):393-395
The hawksbill(Eretmochelys imbricata), an endangered marine turtle associated with coral reefs throughout the tropics, feeds almost exclusively on sponges in the Caribbean, and possibly throughout its range. It is one of fewer than a dozen vertebrates that are known to specialize on this widely distributed but well-defended food resource. The diet is taxonomically narrow and highly uniform geographically, includes sponges that are toxic to other vertebrates, and contains more silica than that of other vertebrates. By affecting space competition, spongivory by hawksbills may influence succession and diversity of reef communities. 相似文献
6.
Carpenter KE Abrar M Aeby G Aronson RB Banks S Bruckner A Chiriboga A Cortés J Delbeek JC Devantier L Edgar GJ Edwards AJ Fenner D Guzmán HM Hoeksema BW Hodgson G Johan O Licuanan WY Livingstone SR Lovell ER Moore JA Obura DO Ochavillo D Polidoro BA Precht WF Quibilan MC Reboton C Richards ZT Rogers AD Sanciangco J Sheppard A Sheppard C Smith J Stuart S Turak E Veron JE Wallace C Weil E Wood E 《Science (New York, N.Y.)》2008,321(5888):560-563
The conservation status of 845 zooxanthellate reef-building coral species was assessed by using International Union for Conservation of Nature Red List Criteria. Of the 704 species that could be assigned conservation status, 32.8% are in categories with elevated risk of extinction. Declines in abundance are associated with bleaching and diseases driven by elevated sea surface temperatures, with extinction risk further exacerbated by local-scale anthropogenic disturbances. The proportion of corals threatened with extinction has increased dramatically in recent decades and exceeds that of most terrestrial groups. The Caribbean has the largest proportion of corals in high extinction risk categories, whereas the Coral Triangle (western Pacific) has the highest proportion of species in all categories of elevated extinction risk. Our results emphasize the widespread plight of coral reefs and the urgent need to enact conservation measures. 相似文献
7.
Roberts CM McClean CJ Veron JE Hawkins JP Allen GR McAllister DE Mittermeier CG Schueler FW Spalding M Wells F Vynne C Werner TB 《Science (New York, N.Y.)》2002,295(5558):1280-1284
Coral reefs are the most biologically diverse of shallow water marine ecosystems but are being degraded worldwide by human activities and climate warming. Analyses of the geographic ranges of 3235 species of reef fish, corals, snails, and lobsters revealed that between 7.2% and 53.6% of each taxon have highly restricted ranges, rendering them vulnerable to extinction. Restricted-range species are clustered into centers of endemism, like those described for terrestrial taxa. The 10 richest centers of endemism cover 15.8% of the world's coral reefs (0.012% of the oceans) but include between 44.8 and 54.2% of the restricted-range species. Many occur in regions where reefs are being severely affected by people, potentially leading to numerous extinctions. Threatened centers of endemism are major biodiversity hotspots, and conservation efforts targeted toward them could help avert the loss of tropical reef biodiversity. 相似文献
8.
Brachiopods and coralline sponges are the dominant taxa of a series of parallel pantropical communities found in cryptic habitats of Recent coral reefs, where these organisms may cover almost the entire available surface area. It is suggested that the continued survival and success of these and other groups of considerable paleontological importance resulted from their occupation of cryptic reef habitats after competition with more rapidly growing hermatypic corals in the Middle Jurassic when scleractinian reefs first appeared. 相似文献
9.
10.
Many physiological responses in present-day coral reefs to climate change are interpreted as consistent with the imminent disappearance of modern reefs globally because of annual mass bleaching events, carbonate dissolution, and insufficient time for substantial evolutionary responses. Emerging evidence for variability in the coral calcification response to acidification, geographical variation in bleaching susceptibility and recovery, responses to past climate change, and potential rates of adaptation to rapid warming supports an alternative scenario in which reef degradation occurs with greater temporal and spatial heterogeneity than current projections suggest. Reducing uncertainty in projecting coral reef futures requires improved understanding of past responses to rapid climate change; physiological responses to interacting factors, such as temperature, acidification, and nutrients; and the costs and constraints imposed by acclimation and adaptation. 相似文献
11.
Hundreds of coral species coexist sympatrically on reefs, reproducing in mass-spawning events where hybridization appears common. In the Caribbean, DNA sequence data from all three sympatric Acropora corals show that mass spawning does not erode species barriers. Species A. cervicornis and A. palmata are distinct at two nuclear loci or share ancestral alleles. Morphotypes historically given the name Acropora prolifera are entirely F(1) hybrids of these two species, showing morphologies that depend on which species provides the egg for hybridization. Although selection limits the evolutionary potential of hybrids, F(1) individuals can reproduce asexually and form long-lived, potentially immortal hybrids with unique morphologies. 相似文献
12.
The relationship between natural variations in coral species diversity, reef development, and ecosystem function on coral reefs is poorly understood. Recent coral diversity varies 10-fold among geographic regions, but rates of reef growth are broadly similar, suggesting that diversity is unimportant for reef development. Differences in diversity may reflect regional differences in long-term biotic history in addition to environmental conditions. Using a combination of new and published fossil and stratigraphic data, we compared changes in coral diversity and reef development within the tropical western Atlantic over the past 28 million years. Reef development was unrelated to coral diversity, and the largest reef tracts formed after extinction had reduced diversity by 50%. High diversity is thus not essential for the growth and persistence of coral reefs. 相似文献
13.
Glynn PW 《Science (New York, N.Y.)》1973,180(4085):504-506
Analysis of data on coral abundance and growth, and the population size (26 individuals per hectare) and feeding rate of Acanthaster indicates that Pocillopora reefs on the Pacific coast of Panama are undergoing vigorous growth in the presence of this predator. Prediction of the effects of a population increase in Acanthaster to plague proportions (2.5 times that presently observed) suggests that reefs could still maintain a positive growth. However, Acanthaster at ten times the present population density would lead to rapid destruction of reefs. It is argued that coral destruction due to Acanthaster represents only one of several factors affecting coral reef progression. 相似文献
14.
Chesher RH 《Science (New York, N.Y.)》1969,165(3890):280-283
Acanthaster planci, a coral predator, is undergoing a population explosion in many areas of the Pacific Ocean. Data on feeding rates, population movements, and stages of infestation were collected along coral reefs of Guam and Palau. Direct observations on destruction of Guam's coral reefs indicate that narrow, fringing reefs may be killed as rapidly as 1 kilometer per month. In a 2(1/2)-year period, 90 percent of the coral was killed along 38 kilometers of Guam's shoreline. 相似文献
15.
Coral reefs under rapid climate change and ocean acidification 总被引：13，自引：0，他引：13
Hoegh-Guldberg O Mumby PJ Hooten AJ Steneck RS Greenfield P Gomez E Harvell CD Sale PF Edwards AJ Caldeira K Knowlton N Eakin CM Iglesias-Prieto R Muthiga N Bradbury RH Dubi A Hatziolos ME 《Science (New York, N.Y.)》2007,318(5857):1737-1742
Atmospheric carbon dioxide concentration is expected to exceed 500 parts per million and global temperatures to rise by at least 2 degrees C by 2050 to 2100, values that significantly exceed those of at least the past 420,000 years during which most extant marine organisms evolved. Under conditions expected in the 21st century, global warming and ocean acidification will compromise carbonate accretion, with corals becoming increasingly rare on reef systems. The result will be less diverse reef communities and carbonate reef structures that fail to be maintained. Climate change also exacerbates local stresses from declining water quality and overexploitation of key species, driving reefs increasingly toward the tipping point for functional collapse. This review presents future scenarios for coral reefs that predict increasingly serious consequences for reef-associated fisheries, tourism, coastal protection, and people. As the International Year of the Reef 2008 begins, scaled-up management intervention and decisive action on global emissions are required if the loss of coral-dominated ecosystems is to be avoided. 相似文献
16.
Normile D 《Science (New York, N.Y.)》2000,290(5492):682-683
Contrary to conventional wisdom, warmer ocean waters are a greater threat to coral reefs than local environmental insults. That assessment comes from a new scientific report released this week that documents a sudden and steep jump in damage stemming from the 1997-98 El Ni?o-La Ni?a event. 相似文献
17.
Mesolella KJ 《Science (New York, N.Y.)》1967,156(3775):638-640
The coral species composition of uplifted Pleistocene reefs on Barbados is very similar to Recent West Indian reefs. Acropora palmata, Acropora cervicornis, and Montastrea annularis are qtuantitatively the most important of the coral species. 相似文献
18.
Pandolfi JM Bradbury RH Sala E Hughes TP Bjorndal KA Cooke RG McArdle D McClenachan L Newman MJ Paredes G Warner RR Jackson JB 《Science (New York, N.Y.)》2003,301(5635):955-958
Degradation of coral reef ecosystems began centuries ago, but there is no global summary of the magnitude of change. We compiled records, extending back thousands of years, of the status and trends of seven major guilds of carnivores, herbivores, and architectural species from 14 regions. Large animals declined before small animals and architectural species, and Atlantic reefs declined before reefs in the Red Sea and Australia, but the trajectories of decline were markedly similar worldwide. All reefs were substantially degraded long before outbreaks of coral disease and bleaching. Regardless of these new threats, reefs will not survive without immediate protection from human exploitation over large spatial scales. 相似文献
19.
Anthropogenic increases of atmospheric carbon dioxide lead to warmer sea surface temperatures and altered ocean chemistry. Experimental evidence suggests that coral calcification decreases as aragonite saturation drops but increases as temperatures rise toward thresholds optimal for coral growth. In situ studies have documented alarming recent declines in calcification rates on several tropical coral reef ecosystems. We show there is no widespread pattern of consistent decline in calcification rates of massive Porites during the 20th century on reefs spanning an 11° latitudinal range in the southeast Indian Ocean off Western Australia. Increasing calcification rates on the high-latitude reefs contrast with the downward trajectory reported for corals on Australia's Great Barrier Reef and provide additional evidence that recent changes in coral calcification are responses to temperature rather than ocean acidification. 相似文献
20.
Measures of growth and skeletal isotopic ratios in the Caribbean coral Montastraea annularis are fundamental to many studies of paleoceanography, environmental degradation, and global climate change. This taxon is shown to consist of at least three sibling species in shallow waters. The two most commonly studied of these show highly significant differences in growth rate and oxygen isotopic ratios, parameters routinely used to estimate past climatic conditions; unusual coloration in the third may have confused research on coral bleaching. Interpretation or comparison of past and current studies can be jeopardized by ignoring these species boundaries. 相似文献