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1.
Regional patterns of evolutionary turnover in Neogene coral reefs from the central Indo-West Pacific Ocean 总被引:1,自引:0,他引:1
The Indo-Pacific is an area of intense ecological interest, not least because of the region’s rich biodiversity. Important
insights into the origins, evolutionary history, and maintenance of Indo-Pacific reef faunas depend upon the analysis of faunal
occurrences derived from detailed stratigraphic sections. We investigated Neogene origination and extinction patterns derived
from a combination of new coral occurrences and previously published records from the central Indo-West Pacific Ocean (cIWP,
Indonesia, Papua New Guinea and Fiji). Two faunal turnover events were observed. In the first, an increase in generic richness
of Scleractinia from the cIWP during the middle Miocene (17–14 Ma) coincided with both large-scale sea level fluctuations
and the great Mid-Miocene collision event. We raise the hypothesis that Mid-Miocene origination was facilitated by habitat
and population fragmentation associated with tectonism and sea level fall. The second, subsequent, turnover event was characterized
by an overall lowering of generic diversity throughout the late Miocene and Pliocene (7–3 Ma), and was followed by a pronounced
pulse of extinction at the Pliocene–Pleistocene boundary (~2.6 Ma). With the exception of the onset of Pleistocene sea-level
cycles and the onset of northern hemisphere glaciation around 2.5 Ma, which might explain increased extinction during this
time interval, there are no tectonic, eustatic, climatic or oceanographic events that neatly coincide with this second episode
of Neogene coral taxonomic turnover. Our results reveal a total of 62 genera, including synonyms, from the Miocene to the
Pleistocene. Neither episode of turnover among coral genera is exactly coincident with turnover in the Atlantic thus regional
environmental change is found to drive Neogene reef dynamics. 相似文献
2.
In recent years, marine scientists have become increasingly alarmed over the decline of live coral cover throughout the Caribbean
and tropical western Atlantic region. The Holocene and Pleistocene fossil record of coral reefs from this region potentially
provides a wealth of long-term ecologic information with which to assess the historical record of changes in shallow water
coral reef communities. Before fossil data can be applied to the modern reef system, critical problems involving fossil preservation
must be addressed. Moreover, it must be demonstrated that the classic reef coral zonation patterns described in the early
days of coral reef ecology, and upon which “healthy” versus “unhealthy” reefs are determined, are themselves representative
of reefs that existed prior to any human influence. To address these issues, we have conducted systematic censuses of life
and death assemblages on modern “healthy” patch reefs in the Florida reef tract that conform to the classic Caribbean model
of reef coral zonation, and a patch reef in the Bahamas that is currently undergoing a transition in coral dominance that
is part of a greater Caribbean-wide phenomenon. Results were compared to censuses of ancient reef assemblages preserved in
Pleistocene limestones in close proximity to each modern reef. We have determined that the Pleistocene fossil record of coral
reefs may be used to calibrate an ecological baseline with which to compare modern reef assemblages, and suggest that the
current and rapid decline of Acropora cervicornis observed on a Bahamian patch reef may be a unique event that contrasts with the long-term persistence of this taxon during
Pleistocene and Holocene time.
Accepted: 19 May 1998 相似文献
3.
A. F. Budd 《Coral reefs (Online)》2000,19(1):25-35
Occurrences of reef corals are examined at Caribbean fossil localities to determine how biodiversity has changed within the
region over the past 50 million years. Analyses of 294 species (66 genera) at 58 fossil localities show that Caribbean generic
diversity rose to 44 between 50–22 Ma, ranged from 32–39 between 22–2 Ma, and dropped to 25 afterwards. Regional species diversity
was high at 40–36 Ma, 28–22 Ma, and 5–2 Ma. Origination rates were elevated throughout each high diversity interval, but extinction
was concentrated near the end of each interval. Regional highs of origination and extinction, therefore, differed in timing
and duration, causing the observed regional diversity increases during the three remarkably long intervals of turnover. Highs
of generic origination decreased in magnitude as immigration from the Mediterranean ceased, but speciation highs increased
in association with emergence of the Central American isthmus. Peaks of extinction coincided with regional changes in climate
and oceanic circulation.
Maximum species diversities within assemblages increased to 40–60 between 50–36 Ma, and have remained relatively constant
ever since. Assemblage compositions differed among localities having similar ages and environments, suggesting that the timing
and pattern of turnover varied across the region. Stable diversities but variable compositions within assemblages suggest
that dispersal and recruitment influenced the pattern of faunal change during turnover.
Accepted: 22 August 1999 相似文献
4.
Mesophotic coral reefs (30–150 m) have been assumed to be physically and biologically connected to their shallow-water counterparts,
and thus may serve as refugia for important taxonomic groups such as corals, sponges, and fish. The recent invasion of the
Indo–Pacific lionfish (Pterois volitans) onto shallow reefs of the Caribbean and Bahamas has had significant, negative, effects on shallow coral reef fish populations.
In the Bahamas, lionfish have extended their habitat range into mesophotic depths down to 91 m where they have reduced the
diversity of several important fish guilds, including herbivores. A phase shift to an algal dominated (>50% benthic cover)
community occurred simultaneously with the loss of herbivores to a depth of 61 m and caused a significant decline in corals
and sponges at mesophotic depths. The effects of this invasive lionfish on mesophotic coral reefs and the subsequent changes
in benthic community structure could not be explained by coral bleaching, overfishing, hurricanes, or disease independently
or in combination. The significant ecological effects of the lionfish invasion into mesophotic depths of coral reefs casts
doubt on whether these communities have the resilience to recover themselves or contribute to the recovery of their shallow
water counterparts as refugia for key coral reef taxa. 相似文献
5.
Fish assemblages on artificial and natural reefs in the Flower Garden Banks National Marine Sanctuary, USA 总被引:5,自引:0,他引:5
Visual censusing was used to characterize fish assemblages on artificial and natural reefs located within the boundaries
of the Flower Garden Banks National Marine Sanctuary (FGBNMS) in the northwestern Gulf of Mexico. Emphasis was placed on determining
spatial and temporal patterns in habitat utilization by fishes on an offshore artificial reef (Mobil Platform HI-A389A). Overall,
43 species were observed during diurnal surveys in the upper 24 m of the artificial reef. Midwater pelagic fishes (i.e., carangids
and scombrids) accounted for over 50% of all taxa enumerated on the artificial reef; however, these taxa were transient members
of the assemblage and were observed infrequently. Labrids, pomacentrids, and serranids were the dominant reef-dependent taxa.
Distinct trends in vertical, diel, and seasonal abundances were observed for juvenile and adult fishes. Of the three designated
depth zones (upper 1.5–9.0, middle 9.0–16.5; lower 16.5–24.0 m), abundance and species diversity were lowest in the upper
zone. Nocturnal counts were characterized by a marked reduction or complete absence of most species, due in part to twilight
cover-seeking and movement activities. Seasonal variation in community composition and species abundance (May versus September)
was primarily due to recruitment of juveniles (0-age fishes) to the artificial reef in late summer. Increases in total fish
abundance (all taxa combined) coincided with both increasing habitat rugosity and degree of fouling. Species richness on natural
coral reefs in the FGBNMS was higher than on the artificial reef. Unlike the artificial reef, fish assemblages on the natural
reefs were dominated by a single family (Pomacentridae) which accounted for over 50% of all individuals observed.
Accepted: 1 August 1996 相似文献
6.
7.
S. Jupiter G. Marion M. Henderson V. Schrameyer M. McCulloch O. Hoegh-Guldberg 《Coral reefs (Online)》2008,27(4):887-903
Coral core records, combined with measurements of coral community structure, were used to assess the long-term impact of multiple
environmental stressors on reef assemblages along an environmental gradient. Multiple proxies (luminescent lines, Ba/Ca, δ15N) that reflect different environmental conditions (freshwater discharge, sediment delivery to the nearshore, nutrient availability
and transformations) were measured in Porites coral cores collected from nearshore reefs at increasing distance from the intensively agricultural region of Mackay (Queensland,
Australia). The corals provide a record (1968–2002) of the frequency and intensity of exposure to terrestrial runoff and fertilizer-derived
nitrogen and were used to assess how the present-day coral community composition may have been influenced by flood-related
disturbance. Reefs closest to the mainland (5–32 km offshore) were characterized by low hard coral cover (≤10%), with no significant
differences among locations. Distinct annual luminescent lines and elevated Ba/Ca values (4.98 ± 0.63 μmol mol−1; mean ± SD) in the most inshore corals (Round Top Island; 5 km offshore) indicated chronic, sub-annual exposure to freshwater
and resuspended terrestrial sediment that may have historically prevented reef formation. By contrast, corals from Keswick
Island (32 km offshore) indicated episodic, high-magnitude exposure to Pioneer River discharge during extreme flood events
(e.g., 1974, 1991), with strongly luminescent lines and substantially enriched coral skeletal δ15N (12–14‰). The reef assemblages at Keswick and St. Bees islands were categorically different from all other locations, with
high fleshy macroalgal cover (80.1 ± 7.2% and 62.7 ± 7.1%, respective mean ± SE) overgrowing dead reef matrix. Coral records
from Scawfell Island (51 km offshore) indicated little exposure to Pioneer catchment influence: all locations from Scawfell
and further offshore had total hard and soft coral cover comparable to largely undisturbed nearshore to middle shelf reefs
of the southern Great Barrier Reef. 相似文献
8.
Reefal units in the early to middle Miocene of Anguilla consist of small, irregular lenses of variable coral composition which developed on a shallow, isolated offshore carbonate platform. They are composed of three distinct coral biofacies (branched, mound-shaped, and platy), which are haphazardly distributed in association with inter-reef sands. These units most probably formed as patch reefs across a broad, shallow area that was exposed to moderate energy conditions and periodically affected by storms. No evidence supports the existence of a more extensive barrier reef system. Comparisons with Oligocene and Mio-Pliocene reefs suggest that during the early to middle Miocene, Caribbean reefs were generally smaller in size (<100 m3) and lower in diversity (21 species in Anguilla, 42 species in total across the Caribbean) than Caribbean reefs during the late Oligocene or during the ate Miocene to early Pliocene (71 species in the Dominican Republic, 80 species total across the Caribbean). The early to middle Miocene Caribbean reef coral fauna was dominated by nine widespread species that occur in deposits of similar age in both Anguilla and Panama. More than half of the fauna consisted of Oligocene relicts. Of the 21 genera that first appeared in the Caribbean during Miocene time, 14 had first occurrences after the middle Miocene, as barrier reef systems became more prevalent across the central Caribbean. 相似文献
9.
D. Lirman T. Thyberg J. Herlan C. Hill C. Young-Lahiff S. Schopmeyer B. Huntington R. Santos C. Drury 《Coral reefs (Online)》2010,29(3):729-735
Coral reef restoration methods such as coral gardening are becoming increasingly considered as viable options to mitigate
reef degradation and enhance recovery of depleted coral populations. In this study, we describe several aspects of the coral
gardening approach that demonstrate this methodology is an effective way of propagating the threatened Caribbean staghorn
coral Acropora cervicornis: (1) the growth of colonies within the nursery exceeded the growth rates of wild staghorn colonies in the same region; (2)
the collection of branch tips did not result in any further mortality to the donor colonies beyond the coral removed for transplantation;
(3) decreases in linear extension of the donor branches were only temporary and donor branches grew faster than control branches
after an initial recovery period of approximately 3–6 weeks; (4) fragmentation did not affect the growth rates of non-donor
branches within the same colony; (5) small branch tips experienced initial mortality due to handling and transportation but
surviving tips grew well over time; and (6) when the growth of the branch tips is added to the regrowth of the fragmented
donor branches, the new coral produced was 1.4–1.8 times more than new growth in undisturbed colonies. Based on these results,
the collection of small (2.5–3.5 cm) branch tips was an effective propagation method for this branching coral species resulting
in increased biomass accumulation and limited damage to parental stocks. 相似文献
10.
Coral growth with thermal stress and ocean acidification: lessons from the eastern tropical Pacific 总被引:1,自引:0,他引:1
D. P. Manzello 《Coral reefs (Online)》2010,29(3):749-758
The rapid growth of scleractinian corals is responsible for the persistence of coral reefs through time. Coral growth rates
have declined over the past 30 years in the western Pacific, Indian, and North Atlantic Oceans. The spatial scale of this
decline has led researchers to suggest that a global phenomenon like ocean acidification may be responsible. A multi-species
inventory of coral growth from Pacific Panamá confirms that declines have occurred in some, but not all species. Linear extension
declined significantly in the most important reef builder of the eastern tropical Pacific, Pocillopora damicornis, by nearly one-third from 1974 to 2006. The rate of decline in skeletal extension for P. damicornis from Pacific Panamá (0.9% year−1) was nearly identical to massive Porites in the Indo-Pacific over the past 20–30 years (0.89–1.23% year−1). The branching pocilloporid corals have shown an increased tolerance to recurrent thermal stress events in Panamá, but appear
to be susceptible to acidification. In contrast, the massive pavonid corals have shown less tolerance to thermal stress, but
may be less sensitive to acidification. These differing sensitivities will be a fundamental determinant of eastern tropical
Pacific coral reef community structure with accelerating climate change that has implications for the future of reef communities
worldwide. 相似文献
11.
T. B. Smith J. Blondeau R. S. Nemeth S. J. Pittman J. M. Calnan E. Kadison J. Gass 《Coral reefs (Online)》2010,29(2):289-308
Coral reef banks may form an important component of mesophotic coral ecosystems (MCEs) in the Caribbean, but remain poorly
explored relative to shallower reefs and mesophotic habitats on slopes and walls. Consequently, the processes structuring
mesophotic coral reef communities are not well understood, particularly the role of disturbance. A large and regionally important
mesophotic system, the Hind Bank Marine Conservation District (MCD), St. Thomas, USVI, was systematically surveyed. Data were
used to construct a comprehensive benthic habitat map for the MCD, describe the abiotic and biotic components of the benthos
among habitats, and investigate patterns of coral health among habitats. Two-thirds of the MCD (23.6 km2) was found to be dense coral reef (Coral Cover = 24.1%) dominated by the Montastraea annularis species complex. Coral reef ecosystems were topographically complex, but could be classified into distinct habitat types,
including high coral banks (35.8% of the MCD) and two large novel coral reef habitat types corresponding to an extremely flat
basin (18%) and a highly rugose hillock basin (6.5%), containing thousands of coral knolls (2–10 m high). An extreme disease
event with undescribed signs of mortality occurred on 47% of coral reefs and reached a high prevalence in affected areas (42.4% ± 6.3
SE, N = 26). The disease was significantly clustered in the basin habitats of the western MCD (global Moran’s I = 0.32, P < 0.01). Observations of the spatial pattern suggested that the driver was specific to the basin habitats and may have been
caused by a coherent abiotic event. 相似文献
12.
New information on the presence and relative abundances of 41 reef-building (zooxanthellate) coral species at 11 eastern
Pacific and 3 central Pacific localities is examined in a biogeographic analysis and review of the eastern Pacific coral reef
region. The composition and origin of the coral fauna and other reef-associated taxa are assessed in the context of dispersal
and vicariance hypotheses. A minimum variance cluster analysis using coral species presence–absence classification data at
the 14 localities revealed three eastern Pacific reef-coral provinces: (1) equatorial– mainland Ecuador to Costa Rica, including the Galápagos and Cocos Islands; (2) northern– mainland México and the Revillagigedo Islands; (3) island group– eastern Pacific Malpelo Island and Clipperton Atoll, and central Pacific Hawaiian, Johnston and Fanning Islands. Coral species
richness is relatively high in the equatorial (17–26 species per locality) and northern (18–24 species) provinces, and low
at two small offshore island localities (7–10 species). A high proportion (36.6%, 15 species) of eastern Pacific coral species
occurs at only one or two localities; of these, three disappeared following the 1982–83 ENSO event, three occur as death assemblages
at several localities, and five are endangered with known populations of ten or fewer colonies. Principal component analysis
using ordinal relative density data for the 41 species at the 14 localities indicated three main species groupings, i.e.,
those with high, mid, and narrow spatial distributions. These groupings correlated with species population-dynamic characteristics.
These results were compared with data for riverine discharges, ocean circulation patterns, shoreline habitat characteristics,
and regional sea surface temperature data to help clarify the analyses as these measures of environmental variability affect
coral community composition. Local richness was highest at localities with the highest environmental variability. Recent information
regarding the strong affinity between eastern and central Pacific coral faunas, abundance of teleplanic larvae in oceanic
currents, high genetic similarity of numerous reef-associated species, and appearances of numerous Indo-west Pacific species
in the east Pacific following ENSO activity, suggest the bridging of the east Pacific filter bridge (formerly east Pacific
barrier).
Accepted: 20 September 1999 相似文献
13.
J. Christine Finney Daniel Tye Pettay Eugenia M. Sampayo Mark E. Warner Hazel A. Oxenford Todd C. LaJeunesse 《Microbial ecology》2010,60(1):250-263
Dinoflagellates in the genus Symbiodinium are among the most abundant and important group of eukaryotic microbes found in coral reef ecosystems. Recent analyses conducted
on various host cnidarians indicated that Symbiodinium assemblages in the Caribbean Sea are genetically and ecologically diverse. In order to further characterize this diversity
and identify processes important to its origins, samples from six orders of Cnidaria comprising 45 genera were collected from
reef habitats around Barbados (eastern Caribbean) and from the Mesoamerican barrier reef off the coast of Belize (western
Caribbean). Fingerprinting of the ribosomal internal transcribed spacer 2 identified 62 genetically different Symbiodinium. Additional analyses of clade B Symbiodinium using microsatellite flanker sequences unequivocally characterized divergent lineages, or “species,” within what was previously
thought to be a single entity (B1 or B184). In contrast to the Indo-Pacific where host-generalist symbionts dominate many coral communities, partner specificity
in the Caribbean is relatively high and is influenced little by the host’s apparent mode of symbiont acquisition. Habitat
depth (ambient light) and geographic isolation appeared to influence the bathymetric zonation and regional distribution for
most of the Symbiodinium spp. characterized. Approximately 80% of Symbiodinium types were endemic to either the eastern or western Caribbean and 40–50% were distributed to compatible hosts living in shallow,
high-irradiance, or deep, low-irradiance environments. These ecologic, geographic, and phylogenetic patterns indicate that
most of the present Symbiodinium diversity probably originated from adaptive radiations driven by ecological specialization in separate Caribbean regions
during the Pliocene and Pleistocene periods. 相似文献
14.
M. J. LeFebvre 《Coral reefs (Online)》2007,26(4):931-944
This paper discusses zooarchaeological analysis of vertebrate faunal specimens from Grand Bay, a Ceramic Age (ca.ad 400–1300) site on the island of Carriacou in the Grenadines, West Indies. Using faunal data to assess subsistence patterns
of vertebrate exploitation during late site occupation, we can begin to better understand Grand Bay procurement strategies
and coral reef exploitation. Preliminary zooarchaeological results imply that Grand Bay vertebrate exploitation emphasized
marine resources over terrestrial resources, with particular emphasis on coral reef habitats and fish. The faunal data are
discussed in relation to common patterns of prehistoric vertebrate exploitation in the Caribbean and fishing strategies. The
Grand Bay faunal sample also provides a foundation from which to formulate future research foci and question zooarchaeological
approaches to understanding prehistoric coral reef exploitation in the Caribbean. 相似文献
15.
Ecological persistence interrupted in Caribbean coral reefs 总被引:2,自引:0,他引:2
The recent mass mortality of Caribbean reef corals dramatically altered reef community structure and begs the question of the past stability and persistence of coral assemblages before human disturbance began. We report within habitat stability in coral community composition in the Pleistocene fossil record of Barbados for at least 95 000 years despite marked variability in global sea level and climate. Results were consistent for surveys of both common and rare taxa. Comparison of Pleistocene and modern community structure shows that Recent human impacts have changed coral community structure in ways not observed in the preceding 220 000 years. 相似文献
16.
S. K. Wilson A. M. Dolman A. J. Cheal M. J. Emslie M. S. Pratchett H. P. A. Sweatman 《Coral reefs (Online)》2009,28(1):3-14
Habitat perturbations play a major role in shaping community structure; however, the elements of disturbance-related habitat
change that affect diversity are not always apparent. This study examined the effects of habitat disturbances on species richness
of coral reef fish assemblages using annual surveys of habitat and 210 fish species from 10 reefs on the Great Barrier Reef
(GBR). Over a period of 11 years, major disturbances, including localised outbreaks of crown-of-thorns sea star (Acanthaster planci), severe storms or coral bleaching, resulted in coral decline of 46–96% in all the 10 reefs. Despite declines in coral cover,
structural complexity of the reef framework was retained on five and species richness of coral reef fishes maintained on nine
of the disturbed reefs. Extensive loss of coral resulted in localised declines of highly specialised coral-dependent species,
but this loss of diversity was more than compensated for by increases in the number of species that feed on the epilithic
algal matrix (EAM). A unimodal relationship between areal coral cover and species richness indicated species richness was
greatest at approximately 20% coral cover declining by 3–4 species (6–8% of average richness) at higher and lower coral cover.
Results revealed that declines in coral cover on reefs may have limited short-term impact on the diversity of coral reef fishes,
though there may be fundamental changes in the community structure of fishes. 相似文献
17.
Ocean temperatures are increasing globally and the Caribbean is no exception. An extreme ocean warming event in 2010 placed Tobago''s coral reefs under severe stress resulting in widespread coral bleaching and threatening the livelihoods that rely on them. The bleaching response of four reef building taxa was monitored over a six month period across three major reefs systems in Tobago. By identifying taxa resilient to bleaching we propose to assist local coral reef managers in the decision making process to cope with mass bleaching events. The bleaching signal (length of exposure to high ocean temperatures) varied widely between the Atlantic and Caribbean reefs, but regardless of this variation most taxa bleached. Colpophyllia natans, Montastraea faveolata and Siderastrea siderea were considered the most bleaching vulnerable taxa. Interestingly, reefs with the highest coral cover showed the greatest decline reef building taxa, and conversely, reefs with the lowest coral cover showed the most bleaching but lowest change in coral cover with little algal overgrowth post-bleaching. 相似文献
18.
19.
Study on rugose coral fauna of the Sifengya Formation (early Telychian) and Daluzhai Formation (mid-late Telychian) in Daguan
area, northeast Yunnan Province, China was carried out. Rugose coral fauna of the Sifengya Formation included 18 genera and
34 species, while Daluzhai Formation with nine genera, ten species. We described rugose coral fauna (12 genera, 19 species)
including one new genus and five new species, i.e. Protoketophyllum daguanense gen. et sp. nov., Crassilasma huanggexiense sp. nov., Pseudophaulactis heae sp. nov., P. convolutus sp. nov., and Shensiphyllum minor sp. nov. The characteristics and geological significance of rugose coral fauna of Sifengya Formation and Daluzhai Formation
were analyzed. Particularly, rugose coral fauna of the Sifengya Formation represent early Telychian rugosan fauna in the Upper
Yangtze region and improve the sequences of early Silurian (Llandovery) rugose coral assemblages in Yangtze region. It is
therefore very meaningful to further analyze radiation period of rugose coral fauna in such epoch.
__________
Translated from Acta Palaeontologica Sinica, 2005, 44(2): 229–246 [译自: 古生物学报, 2005, 44(2): 229–246] 相似文献
20.
Miocene to Pleistocene fossiliferous sediments in the Tugen Hills span the time period from at least 15.5 Ma to 0.25 Ma, including time periods unknown or little known elsewhere in Africa. Consequently, the Tugen Hills deposits hold the potential to inform us about crucial phylogenetic events in African faunal evolution and about long-term environmental change. Among the specimens collected from this region are a number of discoveries already important to the understanding of primate evolution. Here, we describe additional cercopithecoid material from the Miocene deposits in the Tugen Hills sequence, including those from securely dated sites in the Muruyur Beds (16-13.4 Ma), the Mpesida Beds (7-6.2 Ma) and the Lukeino Formation (∼6.2-5.7 Ma). We also evaluate previously described material from the Ngorora Formation (13-8.8 Ma). Identified taxa include Victoriapithecidae gen. et sp. indet., cf. Parapapio lothagamensis, and at least two colobines. Specimens attributed to cf. Pp. lothagamensis would extend the species’ geographic range beyond its type locality. In addition, we describe specimens sharing derived characters with modern African colobines (Tribe: Colobina), a finding that is congruent with previous molecular estimates of colobine divergence dates. These colobine specimens represent some of the earliest known members of the modern African colobine radiation and, in contrast to previous hypotheses, suggest that early African colobines were mainly arboreal and that semi-terrestrial Late Miocene and Plio-Pleistocene colobine taxa were secondarily derived in their locomotor adaptations. 相似文献