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1.
J. M. Lough 《Coral reefs (Online)》1998,17(4):351-367
Significant coral reef ecosystems occur along the northwest (NW) coast of Australia in an oceanographic setting somewhat similar to that of the Great Barrier Reef off the northeast (NE) Australian coast. Seasonal and inter-annual variations of several surface climate variables are described for the NW coastal region of Australia from 10°–30°S over the period 1960 to 1992. Average climatic conditions in this region are compared with those for similar latitudes on the Great Barrier Reef. On average, sea surface temperatures (SSTs) along the NW Australian coast are warmer than at similar latitudes along the NE coast north of ∼20°S and cooler than the NE coast at higher latitudes. The annual range of SSTs along the NW coast is lower than found along the NE coast. There is also lower average cloud amount (and greater incoming solar radiation) along the NW coast compared with the NE coast. Corals reefs off the NW Australian coast are less likely to be influenced by freshwater and associated terrestrial impacts than nearshore reefs of the GBR. Although the latitudinal distribution of tropical cyclone activity is similar along the NW and NE Australian coasts, the total number of tropical cyclones and tropical cyclone days is substantially higher on the NW coast compared with the NE coast. Accepted: 22 June 1998 相似文献
2.
Large-scale bleaching of corals on the Great Barrier Reef 总被引:10,自引:10,他引:10
The Great Barrier Reef (GBR) experienced its most intensive and extensive coral bleaching event on record in early 1998.
Mild bleaching commenced in late January and intensified by late February/early March 1998. Broad-scale aerial surveys conducted
of 654 reefs (∼23% of reefs on the GBR) in March and April 1998, showed that 87% of inshore reefs were bleached at least to
some extent (>1% of coral cover) compared to 28% of offshore (mid- and outer-shelf) reefs. Of inshore reefs 67% had high levels
of bleaching (>10% of coral) and 25% of inshore reefs had extreme levels of bleaching (>60% of coral). Fewer offshore reefs
(14%) showed high levels of bleaching while none showed extreme levels of bleaching. Ground-truth surveys of 23 reefs, which
experienced bleaching in intensities ranging from none to extreme, showed that the aerial survey data are likely to be underestimates
of the true extent and intensity of bleaching on the GBR. The primary cause of this bleaching event is likely to be elevated
sea temperature and solar radiation, exacerbated by lowered salinity on inshore and some offshore reefs in the central GBR.
Accepted: 30 July 1998 相似文献
3.
Adaptation to localised thermal regimes is facilitated by restricted gene flow, ultimately leading to genetic divergence among populations and differences in their physiological tolerances. Allozyme analysis of six polymorphic loci was used to assess genetic differentiation between nine populations of the reef-building coral Acropora millepora over a latitudinal temperature gradient on the inshore regions of the Great Barrier Reef (GBR). Small but significant genetic differentiation indicative of moderate levels of gene flow (pairwise F
ST 0.023 to 0.077) was found between southern populations of A. millepora in cooler regions of the GBR and the warmer, central or northern GBR populations. Patterns of genetic differentiation at these putatively neutral allozyme loci broadly matched experimental variation in thermal tolerance and were consistent with local thermal regimes (warmest monthly-averages) for the A. millepora populations examined. It is therefore hypothesized that natural selection has influenced the thermal tolerance of the A. millepora populations examined and greater genetic divergence is likely to be revealed by examination of genetic markers under the direct effects of natural selection. 相似文献
4.
D. G. Bourne 《Coral reefs (Online)》2005,24(2):304-312
Unusual disease lesions were observed in Montipora corals on the fringing reef of Magnetic Island (Great Barrier Reef, Australia) following a period of high water temperature in early January 2002. Tissue death in Montipora spp. appeared as a black layer that spread rapidly across the colony surface, though this appeared as the final phase of disease progression (with three previous disease phases now identified, S. Anthony, unpublished). Culture and molecular-based microbial analysis of this layer did not identify a likely microbial pathogen. Despite this, DNA sequencing of microbial 16S rDNA indicated a shift in the bacterial population associated with affected coral tissue. A clone library of the healthy coral sample predominantly contained sequences within the -Proteobacteria. A disease coral sample representing the margin of the black lesion and healthy coral tissue was dominated by sequences, which demonstrated low sequence identity to a range of -Proteobacteria, -Proteobacteria and cyanobacteria. The microbes identified in the diseased Montipora spp. samples are likely to be opportunistic rather than the causative agent of the observed lesion. Studies are in progress to further characterise the ecology of this disease and describe the potential microbial pathogen(s). 相似文献
5.
Siwan A. Rees Bradley N. Opdyke Paul A. Wilson L. Keith Fifield Vladimir Levchenko 《Coral reefs (Online)》2006,25(4):555-565
Radiocarbon dating of seven drill cores from both the windward Lizard Island fringing reef and the windward and leeward margins of MacGillivray platform reef, Northern Great Barrier Reef Province, reveal the Holocene evolution of these two mid shelf coral reefs. The windward margin at Lizard Island started growing approximately 6,700 calendar years before present (cal yr BP) directly on an assumed granite basement and approached present day sea level approximately 4,000 cal yr BP. Growth of the windward margin at MacGillivray Reef was initiated by 7,600 cal yr BP and approached present day sea level by approximately 5,600 cal yr BP. The leeward margin at MacGillivray was initiated by 8,200 cal yr BP also directly on an assumed granite basement, but only approached sea level relatively recently, between 260 and 80 cal yr BP. None of the cores penetrated the Holocene-Pleistocene unconformity. The absence of Pleistocene reefal deposits, at 15 m depth in the cores from MacGillivray Reef, raises the possibility that the shelf in this region has subsided relative to modern day sea level by at least 15 m since the last interglacial [125,000 years ago (ka)]. 相似文献
6.
Declining coral calcification in massive Porites in two nearshore regions of the northern Great Barrier Reef 总被引:1,自引:0,他引:1
TIMOTHY F. COOPER † GLENN DE'ATH KATHARINA E. FABRICIUS JANICE M. LOUGH 《Global Change Biology》2008,14(3):529-538
Temporal and spatial variation in the growth parameters skeletal density, linear extension and calcification rate in massive Porites from two nearshore regions of the northern Great Barrier Reef (GBR) were examined over a 16‐year study period. Calcification rates in massive Porites have declined by approximately 21% in two regions on the GBR ~450 km apart. This is a function primarily of a decrease in linear extension (~16%) with a smaller decline in skeletal density (~6%) and contrasts with previous studies on the environmental controls on growth of massive Porites on the GBR. Changes in the growth parameters were linear over time. Averaged across colonies, skeletal density declined over time from 1.32 g cm?3 (SE = 0.017) in 1988 to 1.25 g cm?3 (0.013) in 2003, equivalent to 0.36% yr?1 (0.13). Annual extension declined from 1.52 cm yr?1 (0.035) to 1.28 cm yr?1 (0.026), equivalent to 1.02% yr?1 (0.39). Calcification rates (the product of skeletal density and annual extension) declined from 1.96 g cm?2 yr?1 (0.049) to 1.59 g cm?2 yr?1 (0.041), equivalent to 1.29% yr?1 (0.30). Mean annual seawater temperatures had no effect on skeletal density, but a modal effect on annual extension and calcification with maxima at ~26.7 °C. There were minor differences in the growth parameters between regions. A decline in coral calcification of this magnitude with increasing seawater temperatures is unprecedented in recent centuries based on analysis of growth records from long cores of massive Porites. We discuss the decline in calcification within the context of known environmental controls on coral growth. Although our findings are consistent with studies of the synergistic effect of elevated seawater temperatures and pCO2 on coral calcification, we conclude that further data on seawater chemistry of the GBR are required to better understand the links between environmental change and effects on coral growth. 相似文献
7.
Recruitment of scleractinian corals on settlement plates at Heron Island, Great Barrier Reef, was examined over four years (September 1991–September 1995) to quantify spatio-temporal patterns at different scales and to assess post settlement mortality. Recruitment was dominated by pocilloporid corals which accounted for 80.1% of the 8627 spat counted, whereas non-isoporan acroporids represented only 16.4%. Poritids, faviids and isoporan acroporids rarely recruited to the plates (3.5%), despite their obvious abundance as adults on the reef. Recruitment patterns on the plates indicate strong space-time interactions as evidenced by patchy recruitment of both pocilloporid and acroporid spat. Interactions were found between space (on the scale of 102 m, i.e. sites within zones, and 101 m, i.e. racks within sites) and time (on the scale of years) for pocilloporids and between space (on the scale of 103 m, i.e. zones, and 102 m) and time (on the scale of years) for acroporids. Post-recruitment mortality of acroporid spat in the period 3–10 months after their major spawning was dependent on their initial recruitment density, but pocilloporid mortality was either independent of initial recruitment density or, more likely, obscured by additional recruitment of pocilloporids to plates between late February and September. High rates of recruitment and growth by other sessile organisms, particularly bryozoans and oysters, appear to result in increased post-recruitment mortality and limit recruitment of scleractinian corals on settlement plates. The work reinforces an emerging picture that coral recruitment patterns are determined by mechanisms that manifest over a large range of spatial scales. Accepted: 1 September 1997 相似文献
8.
9.
A comparison of the 1998 and 2002 coral bleaching events on the Great Barrier Reef: spatial correlation,patterns, and predictions 总被引:9,自引:8,他引:9
Detailed mapping of coral bleaching events provides an opportunity to examine spatial patterns in bleaching over scales of 10 s to 1,000 s of km and the spatial correlation between sea surface temperature (SST) and bleaching. We present data for two large-scale (2,000 km) bleaching events on the Great Barrier Reef (GBR): one from 1998 and another from 2002, both mapped by aerial survey methods. We examined a wide range of satellite-derived SST variables to determine which one best correlated with the observed bleaching patterns. We found that the maximum SST occurring over any 3-day period (max3d) during the bleaching season predicted bleaching better than anomaly-based SST variables and that short averaging periods (3–6 days) predicted bleaching better than longer averaging periods. Short periods of high temperature are therefore highly stressful to corals and result in highly predictable bleaching patterns. Max3d SST predicted the presence/absence of bleaching with an accuracy of 73.2%. Large-scale (GBR-wide) spatial patterns of bleaching were similar between 1998 and 2002 with more inshore reefs bleached compared to offshore reefs. Spatial change in patterns of bleaching occurred at scales of ~10 s km, indicating that reefs bleach (or not) in spatial clusters, possibly due to local weather patterns, oceanographic conditions, or both. Approximately 42% of reefs bleached to some extent in 1998 with ~18% strongly bleached, while in 2002, ~54% of reefs bleached to some extent with ~18% strongly bleached. These statistics and the fact that nearly twice as many offshore reefs bleached in 2002 compared to 1998 (41 vs. 21%, respectively) makes the 2002 event the worst bleaching event on record for the GBR. Modeling of the relationship between bleaching and max3d SST indicates that a 1 °C increase would increase the bleaching occurrence of reefs from 50% (approximate occurrence in 1998 and 2002) to 82%, while a 2 °C increase would increase the occurrence to 97% and a 3 °C increase to 100%. These results suggest that coral reefs are profoundly sensitive to even modest increases in temperature and, in the absence of acclimatization/adaptation, are likely to suffer large declines under mid-range International Panel for Climate Change predictions by 2050.
相似文献
Ray BerkelmansEmail: Phone: +61-7-47534268Fax: +61-7-47534429 |
10.
Dynamical seasonal prediction of summer sea surface temperatures in the Great Barrier Reef 总被引:1,自引:0,他引:1
Coral bleaching is a serious problem threatening the world coral reef systems, triggered by high sea surface temperatures
(SST) which are becoming more prevalent as a result of global warming. Seasonal forecasts from coupled ocean–atmosphere models
can be used to predict anomalous SST months in advance. In this study, we assess the ability of the Australian Bureau of Meteorology
seasonal forecast model (POAMA) to forecast SST anomalies in the Great Barrier Reef, Australia, with particular focus on the
major 1998 and 2002 bleaching events. Advance warning of potential bleaching events allows for the implementation of management
strategies to minimise reef damage. This study represents the first attempt to apply a dynamical seasonal model to the problem
of coral bleaching and predict SST over a reef system for up to 6 months lead-time, a potentially invaluable tool for reef
managers.
Communicated by Geology Editor Dr Bernhard Riegl 相似文献
11.
Arthur G. Humes 《Hydrobiologia》1992,234(1):41-57
Three new lichomolgid copepods associated with the scleractinian Gardineroseris planulata (Dana) are described: Sociellus torus, n. gen., n. sp., characterized by a 2-segmented endopod in leg 3 and the lack of an inner seta on the first segment of the
endopod in legs 1–3; Odontomolgus pumilus, n. sp., of very small size and having a much elongated free segment in leg 5 of the female; and Paramolgus ampullaceus, n. sp., distinguished by the bottle-shaped genital segment of the female. In addition, the harpacticoid Alteuthellopsis corallina Humes, 1981, is reported from this coral. With the inclusion of 3 species of the poecilostomatoid genus Xarifia already described (Humes, 1985) there are now 7 species of copepods known to be associated with Gardineroseris planulata on the Great Barrier Reef. 相似文献
12.
Nemerteans of the Great Barrier Reef 1. Anopla Palaeonemertea 总被引:1,自引:0,他引:1
RAY GIBSON 《Zoological Journal of the Linnean Society》1979,65(4):305-337
Two new palaeonemerteans, Carinoma patriciae sp. nov. , and Hubrechtella queenslandica sp. nov. , from the Great Barrier Reef province of Australia, are described and illustrated. The systematic relationships of these nemerteans are discussed and emended diagnoses are given for the genera Carinoma (Carinomidae) and Hubrechtella (Hubrechtidae). 相似文献
13.
K. R. N. Anthony 《Coral reefs (Online)》2000,19(1):59-67
Reef corals occur across a wide range of habitats, from offshore clear waters to nearshore sediment-laden environments. This study tests the hypothesis that corals from turbid nearshore areas have greater capacity to utilise suspended sediment as a food source than conspecifics from less turbid and midshelf areas. The hypothesis was tested on two common and widespread coral species on the Great Barrier Reef (Pocillopora damicornis and Acropora millepora). The particle clearance rates of samples from more turbid reefs were two-fourfold those of conspecifics from less turbid and midshelf reefs. Rates of sediment ingestion were generally a linear function of sediment load indicating no significant saturation within the concentration range of 1–30 mg dry weight l−1. Estimated assimilation efficiency of particulate 14C varied between 50 and 80%, and was maximised for midshelf A. millepora at the lowest sediment concentration, suggesting that heterotrophy is more efficient in oligotrophic habitats. Based on feeding-response curves, assimilation efficiencies, and published records of ambient particle concentrations, representatives of these species on turbid inshore reefs are 10–20 times more heterotrophic on suspended sediment than their conspecifics on less turbid and midshelf reefs. Accepted: 7 September 1999 相似文献
14.
Importance of foraminifera for the formation and maintenance of a coral sand cay: Green Island, Australia 总被引:3,自引:0,他引:3
CaCO3 production by reef-building organisms on Green Island Reef in the Great Barrier Reef of Australia is estimated and compared
with the contribution of benthic foraminifera to the sediment mass of the vegetated sand cay. Major constituents of the cay
are benthic foraminifera (mainly Amphistegina lessonii, Baculogypsina sphaerulata, and Calcarina hispida), calcareous algae (Halimeda and coralline algae), hermatypic corals, and molluscs. Among these reef-building organisms, benthic foraminifera are the
single most important contributor to the sediment mass of the island (ca. 30% of total sediments), although their production
of CaCO3 is smaller than other reef-building organisms. Water current measurements and sediment traps indicate that the velocity of
the current around Green Island is suitable for transportation and deposition of foraminiferal tests. Abundant foraminifera
presently live in association with algal turf on the shallow exposed reef flat, whose tests were accumulated by waves resulting
in the formation and maintenance of the coral sand cay.
Accepted: 30 June 1999 相似文献
15.
The deposition and cycling of carbon and nitrogen in carbonate sediments located between coral reefs on the northern and central
sections of the Great Barrier Reef were examined. Rates of mass sediment accumulation ranged from 1.9 kg m−2 year−1 (inshore reefs) to 2.1–4.9 kg m−2 year−1 (between mid-shelf reefs); sedimentation was minimal off outer-shelf reefs. Rates of total organic carbon decomposition ranged
from 1.7 to 11.4 mol C m−2 year−1 and total nitrogen mineralization ranged from 77 to 438 mmol N m−2 year−1, declining significantly with distance from land. Sediment organic matter was highly reactive, with mineralization efficiencies
ranging from 81 to 99% for organic carbon and 64–100% for nitrogen, with little C and N burial. There was no evidence of carbonate
dissolution/precipitation in short-term incubation experiments. Rates of sulfate reduction (range 0–3.4 mmol S m−2 day−1) and methane release (range 0–12.8 μmol CH4 m−2 day−1) were minor or modest pathways of carbon decomposition. Aerobic respiration, estimated by difference between total O2 consumption and the sum of the other pathways, accounted for 55–98% of total carbon mineralization. Rates of ammonification
ranged from 150 to 1,725 μmol NH4 m−2 day−1, sufficient to support high rates of denitrification (range 30–2,235 μmol N2 m−2 day−1). N2O release was not detected and rates of NH4
+ and NO2
− + NO3
− efflux were low, indicating that most mineralized N was denitrified. The percentage of total N input removed via denitrification
averaged ≈75% (range 28–100%) with little regenerated N available for primary producers. Inter-reef environments are therefore
significant sites of energy and nutrient flow, especially in spatially complex reef matrices such as the Great Barrier Reef. 相似文献
16.
RAY GIBSON 《Zoological Journal of the Linnean Society》1979,66(2):137-160
Three species of heteronemerteans from the Great Barrier Reef province of Australia are described and illustrated. These are Baseodiscus delineatus (Delle Chiaje 1825), Baseodiscus hemprichii (Ehrenberg 1831) and Baseodiscus quinauelineatus (Quoy Sc Gaimard 1833). Baseodiscus hemprichii has not previously been reported from Australia. For all three species a full list of known locations is provided. 相似文献
17.
Epidemiology of skeletal eroding band on the Great Barrier Reef and the role of injury in the initiation of this widespread coral disease 总被引:1,自引:0,他引:1
Skeletal eroding band (SEB), which manifests as dense aggregations of the ciliate Halofolliculina corallasia, was the first coral disease described from the Indo-Pacific. Little is known about its etiology or impact. This study describes
the distribution, prevalence and host range of SEB on a 500 km extent of the Great Barrier Reef (GBR), together with in situ
rates of progression and infection following experimental injury. SEB occurred on 90–100% of reefs surveyed (n=18) in each of 3 years, demonstrating that SEB is widely distributed and persistent. SEB had the highest prevalence of any
disease, affecting approximately 2% of 283,486 scleractinians and hydrocorals surveyed. Its host range was large, affecting
12 families and at least 82 scleractinian species, as well as the hydrocoral, Millepora. Corals in the families Pocilloporidae and Acroporidae were most susceptible, the former being up to five times more susceptible
than other families. Progressive tissue loss was recorded on 95% of Acropora muricata colonies monitored (n = 18), with rates of SEB progression averaging ∼2 mm/day. Injury experiments demonstrated that H. corallasia, the putative pathogen of SEB, readily colonised recently exposed coral skeleton in the absence of a vector, but did not
colonise intact coral tissue. Invading ciliates failed to form band-like aggregations associated with progressive tissue loss
on any of three coral species tested experimentally, suggesting that, while H. corallasia readily colonises recently exposed coral skeleton, it may not be sufficient in itself to cause tissue mortality. Interactions
with additional agents or factors, increasing ciliate virulence or lowering disease resistance of coral hosts may be required
before halofolliculinid infections become associated with tissue loss. 相似文献
18.
Scleractinian coral reefs, when coexistent with siliciclastic sediments, usually occur in association with deltaic or coastal sands. Nevertheless, Pleistocene reef limestones in southwestern Taiwan are developed in association with thick claystones that were deposited in a deeper-water environment. These reef limestones are characterized by: (1) rapid transition from underlying claystones upward to reefal limestones, (2) lateral interfingering with open-shelf claystones, (3) being overlain by terrestrial deposits or exposed with no covering strata, and (4) being located in close association with anticlines. The authors propose that these reef limestones developed on anticlinal ridges raised above the adjacent sea floor by thrust-front migration in a foreland setting. Accepted: 21 April 1998 相似文献
19.
The ecology of the visual pigments of snappers (Lutjanidae) on the Great Barrier Reef 总被引:1,自引:0,他引:1
J. N. Lythgoe W. R. A. Muntz J. C. Partridge J. Shand D. McB. Williams 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1994,174(4):461-467
The visual pigments in the retinal photoreceptors of 12 species of snappers of the genus Lutjanus (Teleostei; Perciformes; Lutjanidae) were measured by microspectrophotometry. All the species were caught on the Great Barrier Reef (Australia) but differ in the colour of the water in which they live. Some live in the clear blue water of the outer reef, some in the greener water of the middle and inshore reefs and some in the more heavily stained mangrove and estuarine water. All the species had double cones, each member of the pair containing a different visual pigment. Using Baker's and Smith's (1982) model to predict the spectral distribution of ambient light from chlorophyll and dissolved organic matter it was found that the absorption spectra of the visual pigments in the double cones were close to those that confer the maximum sensitivity in the different water types. Single cones contained a blue or violet-sensitive visual pigment. The visual pigments in the rods showed little variation, their wavelength of maximum absorption always being in the region 489–502 nm.Abbreviations DOC
dissolved organic carbon
- DOM
dissolved organic material
- MSP
microspectrophotometry
deceased 相似文献
20.
Macroalgae, nutrients and phase shifts on coral reefs: scientific issues and management consequences for the Great Barrier Reef 总被引:13,自引:13,他引:13
L. J. McCook 《Coral reefs (Online)》1999,18(4):357-367
Degradation of coral reefs often involves a “phase shift” from abundant coral to abundant macroalgae. This paper critically
reviews the roles of nutrient increases in such phase shifts. I conclude that nutrient overloads can contribute to reef degradation,
but that they are unlikely to lead to phase shifts simply by enhancing algal growth rates and hence allowing overgrowth of
corals, unless herbivory is unusually or artificially low. Concentrations of dissolved inorganic nutrients are poor indicators
of reef status, and the concept of a simple threshold concentration that indicates eutrophication has little validity. I discuss
the significance and consequences of these assessments for reef management, focusing on the Great Barrier Reef, and conclude
with some specific recommendations, including protection of herbivorous fishes, minimisation of terrestrial runoff, and protection
of coastal reefs.
Accepted: 13 August 1999 相似文献