Coral reef
Marine habitats |
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Coastal habitats |
Ocean surface |
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Open ocean |
Sea floor |
A coral reef is an underwater
Coral belongs to the
Sometimes called rainforests of the sea,
Shallow tropical coral reefs have declined by 50% since 1950, partly because they are sensitive to water conditions.
Coral reefs deliver
Though the shallow water tropical coral reefs are best known, there are also deeper water reef-forming corals, which live in colder water and in temperate seas.
Formation
Most coral reefs were formed after the Last Glacial Period when melting ice caused sea level to rise and flood continental shelves. Most coral reefs are less than 10,000 years old. As communities established themselves, the reefs grew upwards, pacing rising sea levels. Reefs that rose too slowly could become drowned, without sufficient light.[18] Coral reefs are also found in the deep sea away from continental shelves, around oceanic islands and atolls. The majority of these islands are volcanic in origin. Others have tectonic origins where plate movements lifted the deep ocean floor.
In The Structure and Distribution of Coral Reefs,[19] Charles Darwin set out his theory of the formation of atoll reefs, an idea he conceived during the voyage of the Beagle. He theorized that uplift and subsidence of Earth's crust under the oceans formed the atolls.[20] Darwin set out a sequence of three stages in atoll formation. A fringing reef forms around an extinct volcanic island as the island and ocean floor subside. As the subsidence continues, the fringing reef becomes a barrier reef and ultimately an atoll reef.
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Darwin's theory starts with a volcanic island which becomes extinct
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As the island and ocean floor subside, coral growth builds a fringing reef, often including a shallow lagoon between the land and the main reef.
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As the subsidence continues, the fringing reef becomes a larger barrier reef further from the shore with a bigger and deeper lagoon inside.
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Ultimately, the island sinks below the sea, and the barrier reef becomes an atoll enclosing an open lagoon.
Darwin predicted that underneath each lagoon would be a bedrock base, the remains of the original volcano.[21] Subsequent research supported this hypothesis. Darwin's theory followed from his understanding that coral polyps thrive in the tropics where the water is agitated, but can only live within a limited depth range, starting just below low tide. Where the level of the underlying earth allows, the corals grow around the coast to form fringing reefs, and can eventually grow to become a barrier reef.
Where the bottom is rising, fringing reefs can grow around the coast, but coral raised above sea level dies. If the land subsides slowly, the fringing reefs keep pace by growing upwards on a base of older, dead coral, forming a barrier reef enclosing a lagoon between the reef and the land. A barrier reef can encircle an island, and once the island sinks below sea level a roughly circular atoll of growing coral continues to keep up with the sea level, forming a central lagoon. Barrier reefs and atolls do not usually form complete circles but are broken in places by storms. Like
The two main variables determining the geomorphology, or shape, of coral reefs are the nature of the substrate on which they rest, and the history of the change in sea level relative to that substrate.
The approximately 20,000-year-old Great Barrier Reef offers an example of how coral reefs formed on continental shelves. Sea level was then 120 m (390 ft) lower than in the 21st century.[25][26] As sea level rose, the water and the corals encroached on what had been hills of the Australian coastal plain. By 13,000 years ago, sea level had risen to 60 m (200 ft) lower than at present, and many hills of the coastal plains had become continental islands. As sea level rise continued, water topped most of the continental islands. The corals could then overgrow the hills, forming cays and reefs. Sea level on the Great Barrier Reef has not changed significantly in the last 6,000 years.[26] The age of living reef structure is estimated to be between 6,000 and 8,000 years.[27] Although the Great Barrier Reef formed along a continental shelf, and not around a volcanic island, Darwin's principles apply. Development stopped at the barrier reef stage, since Australia is not about to submerge. It formed the world's largest barrier reef, 300–1,000 m (980–3,280 ft) from shore, stretching for 2,000 km (1,200 mi).[28]
Healthy tropical coral reefs grow horizontally from 1 to 3 cm (0.39 to 1.18 in) per year, and grow vertically anywhere from 1 to 25 cm (0.39 to 9.84 in) per year; however, they grow only at depths shallower than 150 m (490 ft) because of their need for sunlight, and cannot grow above sea level.[29]
Material
As the name implies, coral reefs are made up of coral skeletons from mostly intact coral colonies. As other chemical elements present in corals become incorporated into the calcium carbonate deposits,
In the geologic past
The times of maximum reef development were in the
Not all reefs in the past were formed by corals: those in the
Measurements of the oxygen isotopic composition of the aragonitic skeleton of coral reefs, such as
Types
Since Darwin's identification of the three classical reef formations – the fringing reef around a volcanic island becoming a barrier reef and then an atoll[34] – scientists have identified further reef types. While some sources find only three,[35][36] Thomas lists "Four major forms of large-scale coral reefs" – the fringing reef, barrier reef, atoll and table reef based on Stoddart, D.R. (1969).[37][38] Spalding et al. list four main reef types that can be clearly illustrated – the fringing reef, barrier reef, atoll, and "bank or platform reef"—and notes that many other structures exist which do not conform easily to strict definitions, including the "patch reef".[39]
Fringing reef
A fringing reef, also called a shore reef,
Barrier reef
Barrier reefs are separated from a mainland or island shore by a deep channel or lagoon.[42] They resemble the later stages of a fringing reef with its lagoon but differ from the latter mainly in size and origin. Their lagoons can be several kilometres wide and 30 to 70 metres deep. Above all, the offshore outer reef edge formed in open water rather than next to a shoreline. Like an atoll, it is thought that these reefs are formed either as the seabed lowered or sea level rose. Formation takes considerably longer than for a fringing reef, thus barrier reefs are much rarer.
The best known and largest example of a barrier reef is the Australian
Platform reef
Platform reefs, variously called bank or table reefs, can form on the
Platform reefs are typically situated within atolls, where they adopt the name "patch reefs" and often span a diameter of just a few dozen meters. In instances where platform reefs develop along elongated structures, such as old and weathered barrier reefs, they tend to arrange themselves in a linear formation. This is the case, for example, on the east coast of the Red Sea near Jeddah. In old platform reefs, the inner part can be so heavily eroded that it forms a pseudo-atoll.[48] These can be distinguished from real atolls only by detailed investigation, possibly including core drilling. Some platform reefs of the Laccadives are U-shaped, due to wind and water flow.
Atoll
Atolls or
Atolls are found in the Indian Ocean, for example, in the
Other reef types or variants
- Apron reef – short reef resembling a fringing reef, but more sloped; extending out and downward from a point or peninsular shore. The initial stage of a fringing reef.[40]
- Bank reef – isolated, flat-topped reef larger than a patch reef and usually on mid-shelf regions and linear or semi-circular in shape; a type of platform reef.[47]
- Patch reef – common, isolated, comparatively small reef outcrop, usually within a
- Ribbon reef – long, narrow, possibly winding reef, usually associated with an atoll lagoon. Also called a shelf-edge reef or sill reef.[40]
- Drying reef – a part of a reef which is above water at low tide but submerged at high tide[54]
- Habili – reef specific to the Red Sea; does not reach near enough to the surface to cause visible surf; may be a hazard to ships (from the Arabic for "unborn")
- Microatoll – community of species of corals; vertical growth limited by average tidal height; growth morphologies offer a low-resolution record of patterns of sea level change; fossilized remains can be dated using radioactive carbon dating and have been used to reconstruct Holocene sea levels[55]
- Cays – small, low-elevation, sandy islands formed on the surface of coral reefs from eroded material that piles up, forming an area above sea level; can be stabilized by plants to become habitable; occur in tropical environments throughout the Pacific, Atlantic and Indian Oceans (including the Caribbean and on the Great Barrier Reef and Belize Barrier Reef), where they provide habitable and agricultural land
- Seamount or guyot – formed when a coral reef on a volcanic island subsides; tops of seamounts are rounded and guyots are flat; flat tops of guyots, or tablemounts, are due to erosion by waves, winds, and atmospheric processes
Zones
Coral reef ecosystems contain distinct zones that host different kinds of habitats. Usually, three major zones are recognized: the fore reef, reef crest, and the back reef (frequently referred to as the reef lagoon).
The three zones are physically and ecologically interconnected. Reef life and oceanic processes create opportunities for the exchange of seawater, sediments, nutrients and marine life.
Most coral reefs exist in waters less than 50 m deep.[56] Some inhabit tropical continental shelves where cool, nutrient-rich upwelling does not occur, such as the Great Barrier Reef. Others are found in the deep ocean surrounding islands or as atolls, such as in the Maldives. The reefs surrounding islands form when islands subside into the ocean, and atolls form when an island subsides below the surface of the sea.
Alternatively, Moyle and Cech distinguish six zones, though most reefs possess only some of the zones.[57]
The reef surface is the shallowest part of the reef. It is subject to
The off-reef floor is the shallow sea floor surrounding a reef. This zone occurs next to reefs on continental shelves. Reefs around tropical islands and atolls drop abruptly to great depths and do not have such a floor. Usually sandy, the floor often supports seagrass meadows which are important foraging areas for reef fish.
The reef drop-off is, for its first 50 m, habitat for reef fish who find shelter on the cliff face and plankton in the water nearby. The drop-off zone applies mainly to the reefs surrounding oceanic islands and atolls.
The reef face is the zone above the reef floor or the reef drop-off. This zone is often the reef's most diverse area. Coral and
The reef flat is the sandy-bottomed flat, which can be behind the main reef, containing chunks of coral. This zone may border a lagoon and serve as a protective area, or it may lie between the reef and the shore, and in this case is a flat, rocky area. Fish tend to prefer it when it is present.[57]
The reef lagoon is an entirely enclosed region, which creates an area less affected by wave action and often contains small reef patches.[57]
However, the "topography of coral reefs is constantly changing. Each reef is made up of irregular patches of algae,
Locations
Coral reefs are estimated to cover 284,300 km2 (109,800 sq mi),
Although corals exist both in temperate and tropical waters, shallow-water reefs form only in a zone extending from approximately 30° N to 30° S of the equator. Tropical corals do not grow at depths of over 50 meters (160 ft). The optimum temperature for most coral reefs is 26–27 °C (79–81 °F), and few reefs exist in waters below 18 °C (64 °F).[60] When the net production by reef building corals no longer keeps pace with relative sea level and the reef structure permanently drowns a Darwin Point is reached. One such point exists at the northwestern end of the Hawaiian Archipelago; see Evolution of Hawaiian volcanoes#Coral atoll stage.[61][62]
However, reefs in the Persian Gulf have adapted to temperatures of 13 °C (55 °F) in winter and 38 °C (100 °F) in summer.[63] 37 species of scleractinian corals inhabit such an environment around Larak Island.[64]
Deep-water coral inhabits greater depths and colder temperatures at much higher latitudes, as far north as Norway.[65] Although deep water corals can form reefs, little is known about them.
The
Significant coral reefs include:
- The Great Barrier Reef—largest, comprising over 2,900 individual reefs and 900 islands stretching for over 2,600 kilometers (1,600 mi) off Queensland, Australia
- The Bay Islands of Honduras
- The New Caledonia Barrier Reef—second longest double barrier reef, covering 1,500 kilometers (930 mi)
- The Andros, Bahamas Barrier Reef—third largest, following the east coast of Andros Island, Bahamas, between Andros and Nassau
- The Red Sea—includes 6,000-year-old fringing reefs located along a 2,000 km (1,240 mi) coastline
- The Dry Tortugas in the Gulf of Mexico[68]
- Blake Plateau has the world's largest known deep-water coral reef, comprising a 6.4 million acre reef that stretches from Miami to Charleston, S. C. Its discovery was announced in January 2024.[69]
- Pulley Ridge—deepest photosynthetic coral reef, Florida
- Numerous reefs around the Maldives
- The Philippines coral reef area, the second-largest in Southeast Asia, is estimated at 26,000 square kilometres. 915 reef fish species and more than 400 scleractinian coral species, 12 of which are endemic are found there.
- The Raja Ampat Islands in Indonesia's West Papua province offer the highest known marine diversity.[70]
- Bermuda is known for its northernmost coral reef system, located at 32°24′N 64°48′W / 32.4°N 64.8°W. The presence of coral reefs at this high latitude is due to the proximity of the Gulf Stream. Bermuda coral species represent a subset of those found in the greater Caribbean.[71]
- The world's northernmost individual coral reef is located within a bay of Japan's Tsushima Island in the Korea Strait.[72]
- The world's southernmost coral reef is at Lord Howe Island, in the Pacific Ocean off the east coast of Australia.
Coral
When alive, corals are colonies of small animals embedded in calcium carbonate shells. Coral heads consist of accumulations of individual animals called polyps, arranged in diverse shapes.[73] Polyps are usually tiny, but they can range in size from a pinhead to 12 inches (30 cm) across.
Reef-building or hermatypic corals live only in the photic zone (above 70 m), the depth to which sufficient sunlight penetrates the water.[74]
Zooxanthellae
Coral polyps do not photosynthesize, but have a symbiotic relationship with microscopic
The varying pigments in different species of zooxanthellae give them an overall brown or golden-brown appearance and give brown corals their colors. Other pigments such as reds, blues, greens, etc. come from colored proteins made by the coral animals. Coral that loses a large fraction of its zooxanthellae becomes white (or sometimes pastel shades in corals that are pigmented with their own proteins) and is said to be bleached, a condition which, unless corrected, can kill the coral.
There are eight
Clades B and C are found more frequently in deeper water, which may explain their higher vulnerability to increased temperatures. Terrestrial plants that receive less sunlight because they are found in the undergrowth are analogous to clades B, C, and D. Since clades B through D are found at deeper depths, they require an elevated light absorption rate to be able to synthesize as much energy. With elevated absorption rates at UV wavelengths, these phylotypes are more prone to coral bleaching versus the shallow clade A.
Clade D has been observed to be high temperature-tolerant, and has a higher rate of survival than clades B and C during modern bleaching events.[77]
Skeleton
Reefs grow as polyps and other organisms deposit calcium carbonate,
Typical shapes for coral species are named by their resemblance to terrestrial objects such as wrinkled brains, cabbages, table tops, antlers, wire strands and pillars. These shapes can depend on the life history of the coral, like light exposure and wave action,[81] and events such as breakages.[82]
Reproduction
External videos | |
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" Out of Tune - Breakdown of Coral Spawning Synchrony", Tom Shlesinger, Sep 5, 2019. |
Corals reproduce both sexually and asexually. An individual polyp uses both reproductive modes within its lifetime. Corals reproduce sexually by either internal or external fertilization. The reproductive cells are found on the mesenteries, membranes that radiate inward from the layer of tissue that lines the stomach cavity. Some mature adult corals are hermaphroditic; others are exclusively male or female. A few species change sex as they grow.
Internally fertilized eggs develop in the polyp for a period ranging from days to weeks. Subsequent development produces a tiny larva, known as a planula. Externally fertilized eggs develop during synchronized spawning. Polyps across a reef simultaneously release eggs and sperm into the water en masse. Spawn disperse over a large area. The timing of spawning depends on time of year, water temperature, and tidal and lunar cycles. Spawning is most successful given little variation between high and low tide. The less water movement, the better the chance for fertilization. The release of eggs or planula usually occurs at night and is sometimes in phase with the lunar cycle (three to six days after a full moon).[84][85][86]
The period from release to settlement lasts only a few days, but some planulae can survive afloat for several weeks. During this process, the larvae may use several different cues to find a suitable location for settlement. At long distances sounds from existing reefs are likely important,[87] while at short distances chemical compounds become important.[88] The larvae are vulnerable to predation and environmental conditions. The lucky few planulae that successfully attach to substrate then compete for food and space.[citation needed]
Gallery of reef-building corals
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Other reef builders
Coralline algae
Coralline algae are important contributors to reef structure. Although their mineral deposition rates are much slower than corals, they are more tolerant of rough wave-action, and so help to create a protective crust over those parts of the reef subjected to the greatest forces by waves, such as the reef front facing the open ocean. They also strengthen the reef structure by depositing limestone in sheets over the reef surface.[citation needed]
Sponges
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In the northern Pacific Ocean
Bivalves
Hippuritida, an extinct order of bivalves known as rudists, were major reef-building organisms during the Cretaceous. By the mid-Cretaceous, rudists became the dominant tropical reef-builders, becoming more numerous than scleractinian corals. During this period, ocean temperatures and saline levels—which corals are sensitive to—were higher than it is today, which may have contributed to the success of rudist reefs.[32]
Darwin's paradox
Darwin's paradox"Coral... seems to proliferate when ocean waters are warm, poor, clear and agitated, a fact which Darwin had already noted when he passed through Tahiti in 1842. This constitutes a fundamental paradox, shown quantitatively by the apparent impossibility of balancing input and output of the nutritive elements which control the coral polyp metabolism.
Recent oceanographic research has brought to light the reality of this paradox by confirming that the
euphoticzone persists right up to the swell-battered reef crest. When you approach the reef edges and atolls from the quasidesert of the open sea, the near absence of living matter suddenly becomes a plethora of life, without transition. So why is there something rather than nothing, and more precisely, where do the necessary nutrients for the functioning of this extraordinary coral reef machine come from?" — Francis Rougerie[94]
In The Structure and Distribution of Coral Reefs, published in 1842, Darwin described how coral reefs were found in some tropical areas but not others, with no obvious cause. The largest and strongest corals grew in parts of the reef exposed to the most violent surf and corals were weakened or absent where loose sediment accumulated.[19]
Tropical waters contain few nutrients[95] yet a coral reef can flourish like an "oasis in the desert".[96] This has given rise to the ecosystem conundrum, sometimes called "Darwin's paradox": "How can such high production flourish in such nutrient poor conditions?"[97][98][99]
Coral reefs support over one-quarter of all marine species. This diversity results in complex
One reason for the unusual clarity of tropical waters is their nutrient deficiency and drifting plankton. Further, the sun shines year-round in the tropics, warming the surface layer, making it less dense than subsurface layers. The warmer water is separated from deeper, cooler water by a stable thermocline, where the temperature makes a rapid change. This keeps the warm surface waters floating above the cooler deeper waters. In most parts of the ocean, there is little exchange between these layers. Organisms that die in aquatic environments generally sink to the bottom, where they decompose, which releases nutrients in the form of nitrogen (N), phosphorus (P) and potassium (K). These nutrients are necessary for plant growth, but in the tropics, they do not directly return to the surface.[citation needed]
Plants form the base of the food chain and need sunlight and nutrients to grow. In the ocean, these plants are mainly microscopic
Explanations
Around coral reefs, lagoons fill in with material eroded from the reef and the island. They become havens for marine life, providing protection from waves and storms.
Most importantly, reefs recycle nutrients, which happens much less in the open ocean. In coral reefs and lagoons, producers include phytoplankton, as well as seaweed and coralline algae, especially small types called turf algae, which pass nutrients to corals.[103] The phytoplankton form the base of the food chain and are eaten by fish and crustaceans. Recycling reduces the nutrient inputs needed overall to support the community.[76]
Corals also absorb nutrients, including inorganic nitrogen and phosphorus, directly from water. Many corals extend their tentacles at night to catch zooplankton that pass near. Zooplankton provide the polyp with nitrogen, and the polyp shares some of the nitrogen with the zooxanthellae, which also require this element.[103]
Sponges live in crevices in the reefs. They are efficient filter feeders, and in the Red Sea they consume about 60% of the phytoplankton that drifts by. Sponges eventually excrete nutrients in a form that corals can use.[104]
The roughness of coral surfaces is key to coral survival in agitated waters. Normally, a boundary layer of still water surrounds a submerged object, which acts as a barrier. Waves breaking on the extremely rough edges of corals disrupt the boundary layer, allowing the corals access to passing nutrients. Turbulent water thereby promotes reef growth. Without the access to nutrients brought by rough coral surfaces, even the most effective recycling would not suffice.[105]
Deep nutrient-rich water entering coral reefs through isolated events may have significant effects on temperature and nutrient systems.[106][107] This water movement disrupts the relatively stable thermocline that usually exists between warm shallow water and deeper colder water. Temperature regimes on coral reefs in the Bahamas and Florida are highly variable with temporal scales of minutes to seasons and spatial scales across depths.[108]
Water can pass through coral reefs in various ways, including current rings, surface waves, internal waves and tidal changes.[106][109][110][111] Movement is generally created by tides and wind. As tides interact with varying bathymetry and wind mixes with surface water, internal waves are created. An internal wave is a gravity wave that moves along density stratification within the ocean. When a water parcel encounters a different density it oscillates and creates internal waves.[112] While internal waves generally have a lower frequency than surface waves, they often form as a single wave that breaks into multiple waves as it hits a slope and moves upward.[113] This vertical breakup of internal waves causes significant diapycnal mixing and turbulence.[114][115] Internal waves can act as nutrient pumps, bringing plankton and cool nutrient-rich water to the surface.[106][111][116][117][118][119][120][121][122][123][124]
The irregular structure characteristic of coral reef bathymetry may enhance mixing and produce pockets of cooler water and variable nutrient content.[125] Arrival of cool, nutrient-rich water from depths due to internal waves and tidal bores has been linked to growth rates of suspension feeders and benthic algae[111][124][126] as well as plankton and larval organisms.[111][127] The seaweed Codium isthmocladum reacts to deep water nutrient sources because their tissues have different concentrations of nutrients dependent upon depth.[124] Aggregations of eggs, larval organisms and plankton on reefs respond to deep water intrusions.[118] Similarly, as internal waves and bores move vertically, surface-dwelling larval organisms are carried toward the shore.[127] This has significant biological importance to cascading effects of food chains in coral reef ecosystems and may provide yet another key to unlocking the paradox.
Cyanobacteria provide soluble nitrates via nitrogen fixation.[128]
Coral reefs often depend on surrounding habitats, such as seagrass meadows and mangrove forests, for nutrients. Seagrass and mangroves supply dead plants and animals that are rich in nitrogen and serve to feed fish and animals from the reef by supplying wood and vegetation. Reefs, in turn, protect mangroves and seagrass from waves and produce sediment in which the mangroves and seagrass can root.[63]
Biodiversity
Coral reefs form some of the world's most productive ecosystems, providing complex and varied
Reefs are home to a variety of animals, including fish,
The same hideouts in a reef may be regularly inhabited by different species at different times of day. Nighttime predators such as
: 49The great number and diversity of hiding places in coral reefs, i.e. refuges, are the most important factor causing the great diversity and high biomass of the organisms in coral reefs.[133][134]
Coral reefs also have a very high degree of microorganism diversity compared to other environments.[135]
Algae
Reefs are chronically at risk of algal encroachment. Overfishing and excess nutrient supply from onshore can enable algae to outcompete and kill the coral.
Sponges
Sponges are essential for the functioning of the coral reef that system. Algae and corals in coral reefs produce organic material. This is filtered through sponges which convert this organic material into small particles which in turn are absorbed by algae and corals. Sponges are essential to the coral reef system however, they are quite different from corals. While corals are complex and many celled while sponges are very simple organisms with no tissue. They are alike in that they are both immobile aquatic invertebrates but otherwise are completely different.
Types of sponges-
There are several different species of sea sponge. They come in multiple shapes and sizes and all have unique characteristics. Some types of sea sponges include; the tube sponge, vase sponge, yellow sponge, bright red tree sponge, painted tunicate sponge, and the sea squirt sponge.
Medicinal Qualities of Sea Sponges-
Sea sponges have provided the base for many life saving medications. Scientists began to study them in the 1940s and after a few years, discovered that sea sponges contain properties that can stop viral infections. The first drug developed from sea sponges was released in 1969.
Fish
Over 4,000 species of fish inhabit coral reefs.[5] The reasons for this diversity remain unclear. Hypotheses include the "lottery", in which the first (lucky winner) recruit to a territory is typically able to defend it against latecomers, "competition", in which adults compete for territory, and less-competitive species must be able to survive in poorer habitat, and "predation", in which population size is a function of postsettlement piscivore mortality.[141] Healthy reefs can produce up to 35 tons of fish per square kilometre each year, but damaged reefs produce much less.[142]
Invertebrates
Sea urchins,
A number of invertebrates, collectively called "cryptofauna", inhabit the coral skeletal substrate itself, either boring into the skeletons (through the process of
Seabirds
Coral reef systems provide important habitats for seabird species, some endangered. For example, Midway Atoll in Hawaii supports nearly three million seabirds, including two-thirds (1.5 million) of the global population of Laysan albatross, and one-third of the global population of black-footed albatross.[146] Each seabird species has specific sites on the atoll where they nest. Altogether, 17 species of seabirds live on Midway. The short-tailed albatross is the rarest, with fewer than 2,200 surviving after excessive feather hunting in the late 19th century.[147]
Other
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reef fish
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Banded coral shrimp
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Green turtle
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Soft coral, cup coral, sponges and ascidians
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Banded sea krait
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The shell ofLatiaxis wormaldi, a coral snail
Ecosystem services
Coral reefs deliver
The economic cost over a 25-year period of destroying one square kilometre of coral reef has been estimated to be somewhere between $137,000 and $1,200,000.[155]
To improve the management of coastal coral reefs, the
Bermuda's coral reefs provide economic benefits to the Island worth on average $722 million per year, based on six key ecosystem services, according to Sarkis et al (2010).[158]
Shoreline protection
Coral reefs protect shorelines by absorbing wave energy, and many small islands would not exist without reefs. Coral reefs can reduce wave energy by 97%, helping to prevent loss of life and property damage. Coastlines protected by coral reefs are also more stable in terms of erosion than those without. Reefs can attenuate waves as well as or better than artificial structures designed for coastal defence such as breakwaters.[159] An estimated 197 million people who live both below 10 m elevation and within 50 km of a reef consequently may receive risk reduction benefits from reefs. Restoring reefs is significantly cheaper than building artificial breakwaters in tropical environments. Expected damages from flooding would double, and costs from frequent storms would triple without the topmost meter of reefs. For 100-year storm events, flood damages would increase by 91% to $US 272 billion without the top meter.[160]
Fisheries
About six million tons of fish are taken each year from coral reefs. Well-managed reefs have an average annual yield of 15 tons of seafood per square kilometre. Southeast Asia's coral reef fisheries alone yield about $2.4 billion annually from seafood.[155]
Threats
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Chasing Coral – inventing the first time-lapse camera to record bleaching events as they happen (Netflix, full episode) |
Since their emergence 485 million years ago, coral reefs have faced many threats, including disease,
Human activities that threaten coral include coral mining, bottom trawling,[166] and the digging of canals and accesses into islands and bays, all of which can damage marine ecosystems if not done sustainably. Other localized threats include blast fishing, overfishing, coral overmining,[167] and marine pollution, including use of the banned anti-fouling biocide tributyltin; although absent in developed countries, these activities continue in places with few environmental protections or poor regulatory enforcement.[168][169][170] Chemicals in sunscreens may awaken latent viral infections in zooxanthellae[10] and impact reproduction.[171] However, concentrating tourism activities via offshore platforms has been shown to limit the spread of coral disease by tourists.[172]
Greenhouse gas emissions present a broader threat through sea temperature rise and sea level rise, resulting in widespread coral bleaching and loss of coral cover.[173] Climate change causes more frequent and more severe storms, also cchanges ocean circulation patterns, which can destroy coral reefs.[174]Ocean acidification also affects corals by decreasing calcification rates and increasing dissolution rates, although corals can adapt their calcifying fluids to changes in seawater pH and carbonate levels to mitigate the impact.[175][176] Volcanic and human-made aerosol pollution can modulate regional sea surface temperatures.[177]
In 2011, two researchers suggested that "extant marine invertebrates face the same synergistic effects of multiple stressors" that occurred during the
Corals respond to stress by "bleaching", or expelling their colorful
Every 4–7 years, an
A large-scale systematic study of the Jarvis Island coral community, which experienced ten El Niño-coincident coral bleaching events from 1960 to 2016, found that the reef recovered from almost complete death after severe events.[183]
Protection
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Benthic life |
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The effectiveness of MPAs is still debated. For example, a study investigating the success of a small number of MPAs in Indonesia, the Philippines and Papua New Guinea found no significant differences between the MPAs and unprotected sites.[189][190] Furthermore, in some cases they can generate local conflict, due to a lack of community participation, clashing views of the government and fisheries, effectiveness of the area and funding.[191] In some situations, as in the Phoenix Islands Protected Area, MPAs provide revenue to locals. The level of income provided is similar to the income they would have generated without controls.[192] Overall, it appears the MPA's can provide protection to local coral reefs, but that clear management and sufficient funds are required.
The Caribbean Coral Reefs - Status Report 1970–2012, states that coral decline may be reduced or even reversed. For this
Protecting networks of diverse and healthy reefs, not only climate refugia, helps ensure the greatest chance of genetic diversity, which is critical for coral to adapt to new climates.[195] A variety of conservation methods applied across marine and terrestrial threatened ecosystems makes coral adaption more likely and effective.[195]
Designating a reef as a
In Australia, the Great Barrier Reef is protected by the
Inhabitants of Ahus Island,
Increased levels of atmospheric CO2 contribute to ocean acidification, which in turn damages coral reefs. To help combat ocean acidification, several countries have put laws in place to reduce greenhouse gases such as carbon dioxide. Many land use laws aim to reduce CO2 emissions by limiting deforestation. Deforestation can release significant amounts of CO2 absent sequestration via active follow-up forestry programs. Deforestation can also cause erosion, which flows into the ocean, contributing to ocean acidification. Incentives are used to reduce miles traveled by vehicles, which reduces carbon emissions into the atmosphere, thereby reducing the amount of dissolved CO2 in the ocean. State and federal governments also regulate land activities that affect coastal erosion.[201] High-end satellite technology can monitor reef conditions.[202]
The United States Clean Water Act puts pressure on state governments to monitor and limit run-off of polluted water.
Restoration
Coral reef restoration has grown in prominence over the past several decades because of the unprecedented reef die-offs around the planet. Coral stressors can include pollution, warming ocean temperatures, extreme weather events, and overfishing. With the deterioration of global reefs, fish nurseries, biodiversity, coastal development and livelihood, and natural beauty are under threat. Fortunately, researchers have taken it upon themselves to develop a new field, coral restoration, in the 1970s-1980s[203]
Coral farming
Coral gardens take advantage of a coral's natural ability to fragment and continuing to grow if the fragments are able to anchor themselves onto new substrates. This method was first tested by Baruch Rinkevich[209] in 1995 which found success at the time. By today's standards, coral farming has grown into a variety of different forms, but still has the same goals of cultivating corals. Consequently, coral farming quickly replaced previously used transplantation methods or the act of physically moving sections or whole colonies of corals into a new area.[208] Transplantation has seen success in the past and decades of experiments have led to a high success and survival rate. However, this method still requires the removal of corals from existing reefs. With the current state of reefs, this kind of method should generally be avoided if possible. Saving healthy corals from eroding substrates or reefs that are doomed to collapse could be a major advantage of utilizing transplantation.
Coral gardens generally take on the safe forms no matter where you go. It begins with the establishment of a nursery where operators can observe and care for coral fragments.[208] It goes without saying that nurseries should be established in areas that are going to maximize growth and minimize mortality. Floating offshore coral trees or even aquariums are possible locations where corals can grow. After a location has been determined, collection and cultivation can occur.
The major benefit of using coral farms is it lowers polyp and juvenile mortality rates. By removing predators and recruitment obstacles, corals are able to mature without much hindrance. However, nurseries cannot stop climate stressors. Warming temperatures or hurricanes can still disrupt or even kill nursery corals.
Technology is becoming more popular in the coral farming process. Teams from the Reef Restoration and Adaptation Program (RRAP) have trialled coral counting technology utilizing a prototype robotic camera. The camera uses computer vision and learning algorithms to detect and count individual coral babies and track their growth and health in real time. This technology, with research led by QUT, is intended to be used during annual coral spawning events and will provide researchers with control that is not currently possible when mass producing corals.[210]
Creating substrates
Efforts to expand the size and number of coral reefs generally involve supplying substrate to allow more corals to find a home. Substrate materials include discarded vehicle tires, scuttled ships, subway cars and formed concrete, such as
Simply having many structures on the ocean floor is not enough to form coral reefs. Restoration projects must consider the complexity of the substrates they are creating for future reefs. Researchers conducted an experiment near Ticao Island in the Philippines in 2013[211] where several substrates in varying complexities were laid in the nearby degraded reefs. Large complexity consisted of plots that had both a human-made substrates of both smooth and rough rocks with a surrounding fence, medium consisted of only the human-made substrates, and small had neither the fence or substrates. After one month, researchers found that there was a positive correlation between structure complexity and recruitment rates of larvae.[211] The medium complexity performed the best with larvae favoring rough rocks over smooth rocks. Following one year of their study, researchers visited the site and found that many of the sites were able to support local fisheries. They came to the conclusion that reef restoration could be done cost-effectively and will yield long term benefits given they are protected and maintained.[211]
Relocation
One case study with coral reef restoration was conducted on the island of
Dredging covers corals with sand. Coral larvae cannot settle on sand; they can only build on existing reefs or compatible hard surfaces, such as rock or concrete. Because of this, the university decided to relocate some of the coral. They transplanted them with the help of United States Army divers, to a site relatively close to the channel. They observed little if any damage to any of the colonies during transport and no mortality of coral reefs was observed on the transplant site. While attaching the coral to the transplant site, they found that coral placed on hard rock grew well, including on the wires that attached the corals to the site.
No environmental effects were seen from the transplantation process, recreational activities were not decreased, and no scenic areas were affected.
As an alternative to transplanting coral themselves, juvenile fish can also be encouraged to relocate to existing coral reefs by auditory simulation. In damaged sections of the Great Barrier Reef, loudspeakers playing recordings of healthy reef environments were found to attract fish twice as often as equivalent patches where no sound was played, and also increased species biodiversity by 50%.
Heat-tolerant symbionts
Another possibility for coral restoration is gene therapy: inoculating coral with
The first method is to induce acclimatization of the first generation of corals.[213] The idea is that when adult and offspring corals are exposed to stressors, the zooxanthellae will gain a mutation. This method is based mostly on the chance that the zooxanthellae will acquire the specific trait that will allow it to better survive in warmer waters. The second method focuses on identifying what different kinds of zooxanthellae are within the coral and configuring how much of each zooxanthella lives within the coral at a given age.[213] Use of zooxanthellae from the previous method would only boost success rates for this method. However, this method would only be applicable to younger corals, for now, because previous experiments of manipulation zooxanthellae communities at later life stages have all failed. The third method focuses on selective breeding tactics.[213] Once selected, corals would be reared and exposed to simulated stressors in a laboratory. The last method is to genetically modify the zooxanthellae itself.[213] When preferred mutations are acquired, the genetically modified zooxanthellae will be introduced to an aposymbiotic poly and a new coral will be produced. This method is the most laborious of the fourth, but researchers believe this method should be utilized more and holds the most promise in genetic engineering for coral restoration.
Invasive algae
Hawaiian coral reefs smothered by the spread of invasive algae were managed with a two-prong approach: divers manually removed invasive algae, with the support of super-sucker barges. Grazing pressure on invasive algae needed to be increased to prevent the regrowth of the algae. Researchers found that native collector urchins were reasonable candidate grazers for algae biocontrol, to extirpate the remaining invasive algae from the reef.[144]
Invasive algae in Caribbean reefs
Macroalgae, or better known as seaweed, has to potential to cause reef collapse because they can outcompete many coral species. Macroalgae can overgrow on corals, shade, block recruitment, release biochemicals that can hinder spawning, and potentially form bacteria harmful to corals.[214][215] Historically, algae growth was controlled by herbivorous fish and sea urchins. Parrotfish are a prime example of reef caretakers. Consequently, these two species can be considered as keystone species for reef environments because of their role in protecting reefs.
Before the 1980s, Jamaica's reefs were thriving and well cared for, however, this all changed after Hurricane Allen occurred in 1980 and an unknown disease spread across the Caribbean. In the wake of these events, massive damage was caused to both the reefs and sea urchin population across Jamaican's reefs and into the Caribbean Sea. As little as 2% of the original sea urchin population survived the disease.[215] Primary macroalgae succeeded the destroyed reefs and eventually larger, more resilient macroalgae soon took its place as the dominant organism.[215][216] Parrotfish and other herbivorous fish were few in numbers because of decades of overfishing and bycatch at the time.[216] Historically, the Jamaican coast had 90% coral cover and was reduced to 5% in the 1990s.[216] Eventually, corals were able to recover in areas where sea urchin populations were increasing. Sea urchins were able to feed and multiply and clear off substrates, leaving areas for coral polyps to anchor and mature. However, sea urchin populations are still not recovering as fast as researchers predicted, despite being highly fecundate.[215] It is unknown whether or not the mysterious disease is still present and preventing sea urchin populations from rebounding. Regardless, these areas are slowly recovering with the aid of sea urchin grazing. This event supports an early restoration idea of cultivating and releasing sea urchins into reefs to prevent algal overgrowth.[217][218]
Microfragmentation and f
014, Christopher Page, Erinn Muller, and David Vaughan from the International Center for Coral Reef Research & Restoration at Mote Marine Laboratory in Summerland Key, Florida developed a new technology called "microfragmentation", in which they use a specialized diamond band saw to cut corals into 1 cm2 fragments instead of 6 cm2 to advance the growth of brain, boulder, and star corals.[219] Corals Orbicella faveolata and Montastraea cavernosa were outplanted off the Florida's shores in several microfragment arrays. After two years, O. faveolata had grown 6.5x its original size while M. cavernosa had grown nearly twice its size.[219] Under conventional means, both corals would have required decades to reach the same size. It is suspected that if predation events had not occurred near the beginning of the experiment O. faveolata would have grown at least ten times its original size.[219] By using this method, Mote Marine Laboratory successfully generated 25,000 corals within a single year, subsequently transplanting 10,000 of them into the Florida Keys. Shortly after, they discovered that these microfragments fused with other microfragments from the same parent coral. Typically, corals that are not from the same parent fight and kill nearby corals in an attempt to survive and expand. This new technology is known as "fusion" and has been shown to grow coral heads in just two years instead of the typical 25–75 years. After fusion occurs, the reef will act as a single organism rather than several independent reefs. Currently, there has been no published research into this method.[219]
See also
- Deep-water coral — Corals living in the cold waters of deeper, darker parts of the oceans
- Mesophotic coral reef — Corals living in the mesopelagic or twilight zone
- Fossil Coral Reef – National Natural Landmark in Le Roy, New York
- Census of Coral Reefs – Field project of the Census of Marine Life
- Catlin Seaview Survey
- Coral reef organizations – U.S. Coral Reef Task Force
- Sponge reef
- Pseudo-atoll – Island that encircles a lagoon
References
- ^ "How Reefs Are Made". Coral Reef Alliance. 2021. Archived from the original on 30 October 2021. Retrieved 19 April 2022.
- ISSN 0012-8252.
- ^ Coral reefs NOAA National Ocean Service. Accessed: 10 January 2020.
- S2CID 46114284.
- ^ ISBN 0520232550.
- ^ Mulhall, M. (Spring 2009). "Saving rainforests of the sea: An analysis of international efforts to conserve coral reefs". Duke Environmental Law and Policy Forum. 19: 321–351. Archived from the original on 6 January 2010.
- NOAA. 13 May 2011. Archived from the originalon 4 March 2016. Retrieved 24 March 2015.
- ISBN 978-1-56647-220-3.
- ^ Greenfield, Patrick (17 September 2021). "Global coral cover has fallen by half since 1950s, analysis finds". The Guardian. Retrieved 18 September 2021.
- ^ PMID 18414624.
- ^ "Corals reveal impact of land use". ARC Centre of Excellence for Coral Reef Studies. Retrieved 21 September 2013.
- ^ Minato, Charissa (1 July 2002). "Urban runoff and coastal water quality being researched for effects on coral reefs" (PDF). Archived from the original (PDF) on 10 June 2010.
- ^ "Coastal Watershed Factsheets – Coral Reefs and Your Coastal Watershed". Environmental Protection Agency Office of Water. July 1998. Archived from the original on 30 August 2010.
- ^ a b Cesar, H.J.S.; Burke, L.; Pet-Soede, L. (2003). The Economics of Worldwide Coral Reef Degradation. The Netherlands: Cesar Environmental Economics Consulting. p. 4. Retrieved 21 September 2013. (pdf: link)
- ^ S2CID 672256.
- ^ "The Sixth Status of Corals of the World: 2020 Report". GCRMN. Retrieved 5 October 2021.
- S2CID 15215236.
- ^ Kleypas, Joanie (2010). "Coral reef". The Encyclopedia of Earth. Archived from the original on 15 August 2010. Retrieved 4 April 2011.
- ^ a b Darwin, Charles R. (1842). The Structure and Distribution of Coral Reefs. Being the first part of the geology of the voyage of the Beagle, under the command of Capt. Fitzroy, R.N. during the years 1832 to 1836. London: Smith Elder and Co. Via Internet Archive
- ^ Chancellor, Gordon (2008). "Introduction to Coral reefs". Darwin Online. Retrieved 20 January 2009.
- ^ "4 Main Theories of Coral Reefs and Atolls/Oceans/Geography". Geography Notes. 11 March 2017. Retrieved 1 August 2020.
- ^ Animation of coral atoll formation Archived July 14, 2012, at the Wayback Machine NOAA Ocean Education Service. Retrieved January 9, 2010.
- .
- doi:10.1130/G20170.1.
- ^ Reef Facts for Tour Guides: A "big picture" view of the Great Barrier Reef (PDF) (Report). Great Barrier Reef Marine Park Authority. 2006. Archived from the original (PDF) on 20 June 2007. Retrieved 18 June 2007.
- ^ a b Tobin, Barry (2003) [1998]. "How the Great Barrier Reef was formed". Australian Institute of Marine Science. Archived from the original on 5 October 2006. Retrieved 22 November 2006.
- ^ CRC Reef Research Centre Ltd. "What is the Great Barrier Reef?". Archived from the original on 22 August 2006. Retrieved 28 May 2006.
- ^ Four Types of Coral Reef Archived 24 October 2012 at the Wayback Machine Microdocs, Stanford Education. Retrieved January 10, 2010.
- ^ MSN Encarta (2006). Great Barrier Reef. Archived from the original on 28 October 2009. Retrieved 11 December 2006.
- ^ ISBN 978-0-87850-138-0.
- ISBN 978-0-412-03541-8, retrieved 15 February 2024)
{{citation}}
: CS1 maint: DOI inactive as of March 2024 (link - ^ S2CID 121693025.
- S2CID 6088699. Archived from the original(PDF) on 11 January 2012.
- ^ Hopley, David (ed.) Encyclopedia of Modern Coral Reefs Dordrecht: Springer, 2011. p. 40.
- ^ e.g. Unit 10: Reef Types in the Coral Reef Ecology Curriculum. Retrieved 1 Feb 2018.
- ISBN 0-14-051094-X.
- ISBN 9781118782347.
- S2CID 85873056.
- ISBN 0-520-23255-0.
- ^ a b c National Oceanic and Atmospheric Administration. Coral Reef Information System Glossary, 2014.
- ^ Fringing Reefs (Shore Reefs) at www.pmfias.com. Retrieved 2 Feb 2018.
- ^ a b c d e f Types of Coral Reef Formations at coral.org. Retrieved 2 Feb 2018.
- ^ McClanahan, C.R.C. Sheppard and D.O. Obura. Coral Reefs of the Indian Ocean: Their Ecology and Conservation. Oxford: OUP, 2000, p. 136.
- ^ Goudie, Andrew. Encyclopedia of Geomorphology, London: Routledge, 2004, p. 411.
- ^ Ghiselin, Michael T. The Triumph of the Darwinian Method. Berkeley, University of California, 1969, p. 22.
- ^ Hanauer, Eric. The Egyptian Red Sea: A Diver's Guide. San Diego: Watersport, 1988, p. 74.
- ^ a b c d e f g Types of Coral Reefs Archived September 13, 2017, at the Wayback Machine at www.coral-reef-info.com. Retrieved 2 Feb 2018.
- ^ ISBN 978-3-423-03422-7.)
{{cite encyclopedia}}
: CS1 maint: location missing publisher (link - .
- ^ Jell JS, Flood PG (April 1978). "Guide to the geology of reefs of the Capricorn and Bunker groups, Great Barrier Reef province". Papers, Department of Geology. 8 (3). pp. 1–85, pls. 1-17. Retrieved 28 June 2018.
- ^ Hopley, David. Encyclopedia of Modern Coral Reefs: Structure, Form and Process. Dordrecht: Springer, 2011, p. 51.
- ^ Maldives Atolls at www.mymaldives.com. Retrieved 2 Feb 2018.
- (PDF) from the original on 9 October 2022, retrieved 24 April 2019
- ISSN 0268-0106.
- .
- ^ "Coral Reefs". marinebio.org. 17 June 2018. Retrieved 28 October 2022.
- ^ ISBN 978-0-13-100847-2.
- PMID 17840770.
- Coral Reef Unit
- ^ Achituv, Y. and Dubinsky, Z. 1990. Evolution and Zoogeography of Coral Reefs Ecosystems of the World. Vol. 25:1–8.
- ^ Grigg, R.W. (2011). Darwin Point. In: Hopley, D. (eds) Encyclopedia of Modern Coral Reefs. Encyclopedia of Earth Sciences Series. Springer, Dordrecht. https://doi.org/10.1007/978-90-481-2639-2_66
- ^ G. Flood, The ‘Darwin Point’ of Pacific Ocean atolls and guyots: a reappraisal, Palaeogeography, Palaeoclimatology, Palaeoecology, Volume 175, Issues 1–4, 2001, Pages 147-152, ISSN 0031-0182, https://doi.org/10.1016/S0031-0182(01)00390-X.
- ^ ISBN 978-0-8069-8795-8.
- PMID 26042286.
- ^ Gunnerus, Johan Ernst (1768). Om Nogle Norske Coraller.
- ^ "Coral reef in Eilat, the northernmost reef in the world, is growing". The Jerusalem Post | JPost.com. 5 August 2018. Retrieved 4 March 2024.
- ^ a b Nybakken, James. 1997. Marine Biology: An Ecological Approach. 4th ed. Menlo Park, CA: Addison Wesley.
- ^ NOAA CoRIS – Regional Portal – Florida. Coris.noaa.gov (August 16, 2012). Retrieved on March 3, 2013.
- .
- ^ NGM.nationalgeographic.com, Ultra Marine: In far eastern Indonesia, the Raja Ampat islands embrace a phenomenal coral wilderness, by David Doubilet, National Geographic, September 2007
- ^ Living Reefs Foundation. Retrieved on May 28, 2015.
- ^ LiveScience. Retrieved on April 14, 2016.
- ^ Sherman, C.D.H. (2006). The Importance of Fine-scale Environmental Heterogeneity in Determining Levels of Genotypic Diversity and Local Adaption (PDF) (Ph.D. thesis). University of Wollongong. Archived from the original (PDF) on 24 July 2008. Retrieved 7 June 2009.
- ^ "What are Coral Reefs". Coral Reef Information System (CoRIS). National Oceanic and Atmospheric Administration. Retrieved 9 November 2022.
- ^ Zooxanthellae… What's That?. Oceanservice.noaa.gov (March 25, 2008). Retrieved on November 1, 2011.
- ^ ISBN 978-1-876945-40-4.
- ^ PMID 18757737.
- ^ Stacy J, Marion G, McCulloch M, Hoegh-Guldberg O (May 2007). "Long-term changes to Mackay Whitsunday water quality and connectivity between terrestrial, mangrove and coral reef ecosystems: Clues from coral proxies and remote sensing records" (PDF). Centre for Marine Studies. Synthesis of research from an ARC Linkage Grant (2004–2007). University of Queensland. Archived from the original (PDF) on 30 August 2007. Retrieved 7 June 2009.
- ^ Nothdurft, Luke D. (2007). Microstructure and early diagenesis of recent reef building scleractinian corals, Heron reef, Great Barrier Reef: implications for paleoclimate analysis (PDF) (Ph.D. thesis). Queensland University of Technology (published 2008). Archived (PDF) from the original on 9 March 2011. Retrieved 10 November 2022. Via QUT ePrints Archived 11 November 2022 at the Wayback Machine
- ^ Wilson RA (9 August 2007). "The Biological Notion of Individual". Stanford Encyclopedia of Philosophy. Retrieved 7 June 2009.
- S2CID 4347930.
- JSTOR 1311805.
- ^ Are corals animals or plants? NOAA: National Ocean Service. Accessed 11 February 2020. Updated: 7 January 2020.
- . Retrieved 6 March 2023.
- ^ S2CID 251865474.
- PMID 34373318.
- PMID 20498831.
- S2CID 39726375.
- ^ "Fluorescent coral". photography. Coral kingdoms. National Geographic Society. Archived from the original on 29 June 2010.
- ISBN 978-0-632-05098-7.
- S2CID 127193540.
- overharvestingthe American oyster, Crassostrea virginica? In: M. Lynch and E.C. Krome (eds.) Understanding the estuary: advances in Chesapeake Bay research, Chesapeake Research Consortium, Solomons MD pp.536-546.
- Department for Environment and Water. 10 May 2019. Retrieved 28 February 2021.
- ISBN 978-1-876542-02-3. (pdf: link).
- ISBN 9780642895851.
- ^ Odum, E.P. (1971). Fundamentals of Ecology (3rd ed.). Saunders.
- .
- S2CID 27590358.
- ^ De Goeij, Jasper M (2009) "Element cycling on tropical coral reefs: the cryptic carbon shunt revealed" PhD thesis, page 13. University of Groningen.
- ISBN 978-0-387-56427-2.
- PMID 21227159.
- ISSN 0171-8630.
- ^ a b c Castro, Peter and Huber, Michael (2000) Marine Biology. 3rd ed. Boston: McGraw-Hill.
- National Geographic News. Archived from the originalon 8 November 2001. Retrieved 5 April 2011.
- ^ Nowak, Rachel (21 September 2002). "Corals play rough over Darwin's paradox". New Scientist (2361).
- ^ .
- .
- .
- S2CID 55252988.
- (PDF) from the original on 9 October 2022.
- ^ .
- ISBN 978-0750645522.
- S2CID 122915102.
- .
- S2CID 121973787.
- .
- .
- ^ S2CID 19757639.
- (PDF) from the original on 9 October 2022.
- .
- S2CID 42822848.
- .
- .
- ^ S2CID 15125174.
- (PDF) from the original on 9 October 2022.
- .
- ^ .
- .
- ISBN 978-0-632-02983-9.
- ^ Fuchs. T (2013). "Effects of Coral Reef Complexity on Invertebrate Biodiversity". Immediate Science Ecology Publishing: 1–10. Archived from the original on 2 April 2015.
- ISBN 978-0-08-037718-6.
- ^ "World's Reef Fishes Tussling With Human Overpopulation". ScienceDaily. 5 April 2011.
- ISSN 0022-1112.
- PMID 23457533.
- PMID 37264002.
- NOAA. Archived from the originalon 27 September 2011. Retrieved 6 April 2011.
- ISBN 978-0-444-87392-7.
- PMID 27114888.
- ^ "THE EFFECTS OF TERRESTRIAL RUNOFF OF SEDIMENTS, NUTRIENTS AND OTHER POLLUTANTS ON CORAL REEFS" (PDF). Archived from the original (PDF) on 4 March 2016. Retrieved 5 December 2015.
- .
- ^ Buchheim, Jason. "Coral Reef Fish Ecology". marinebiology.org. Retrieved 5 April 2011.
- ^ McClellan, Kate; Bruno, John (2008). "Coral degradation through destructive fishing practices". Encyclopedia of Earth. Retrieved 25 October 2008.
- ISBN 978-0-521-64523-2.
- ^ PMID 26401450.
- S2CID 33874352.
- ^ Midway's albatross population stable Archived 27 December 2016 at the Wayback Machine. The.honoluluadvertiser.com (January 17, 2005). Retrieved on November 1, 2011.
- ^ "U.S. Fish & Wildlife Service – Birds of Midway Atoll". Archived from the original on 22 May 2013. Retrieved 19 August 2009.
- ISBN 978-1-57524-116-6.
- S2CID 17572816.
- JSTOR 1935755.
- .
- ISBN 978-0849384226.
- S2CID 22971831.
- .
- ^ World Wildlife Fund. Archived from the originalon 10 July 2010. Retrieved 7 April 2011.
- ^ "Coastal Capital: Economic Valuation of Coastal Ecosystems in the Caribbean". World Resources Institute. 19 February 2014.
- ^ Cooper, Emily; Burke, Lauretta; Bood, Nadia (2008). "Coastal Capital: Belize: The Economic Contribution of Belize's Coral Reefs and Mangroves" (PDF). Archived (PDF) from the original on 9 October 2022. Retrieved 6 April 2011.
- ^ Sarkis, Samia; van Beukering, Pieter J.H.; McKenzie, Emily (2010). "Total Economic Value of Bermuda's Coral Reefs. Valuation of ecosystem Services" (PDF). Archived (PDF) from the original on 9 October 2022. Retrieved 29 May 2015.
- PMID 24825660.
- PMID 29895942.
- Guardian.co.uk. 2 September 2009.
- ISBN 978-94-017-7248-8.
- ISSN 0022-5193.
- S2CID 34046524.
- ^ Visser, Nick (5 October 2021). "Planet Lost Startling Amount Of Coral Reefs In 10 Years, Report Finds". HuffPost. Archived from the original on 5 October 2021. Retrieved 5 October 2021.
- ISSN 1439-0485.
- ISSN 0964-5691.
- ^ "Blast fishing". Stop Illegal Fishing. Retrieved 15 November 2019.
- ^ "Magnuson-Stevens Act: A unique charge for sustainable seafood | National Oceanic and Atmospheric Administration". www.noaa.gov. Retrieved 15 November 2019.
- ^ "Coral". US Fish and Wildlife Service. Archived from the original on 29 May 2020. Retrieved 15 November 2019.
- ^ Stierwalt, Everyday Einstein Sabrina. "Why Is Hawaii Banning Sunscreen?". Scientific American. Retrieved 19 August 2018.
- S2CID 12979332.
- ^ "Caribbean coral reefs may disappear within 20 years: Report". IANS. news.biharprabha.com. Retrieved 3 July 2014.
- ^ How does climate change affect coral reefs?
- PMID 28555644.
- ^ Cooley, S., D. Schoeman, L. Bopp, P. Boyd, S. Donner, D.Y. Ghebrehiwet, S.-I. Ito, W. Kiessling, P. Martinetto, E. Ojea, M.-F. Racault, B. Rost, and M. Skern-Mauritzen, 2022: Chapter 3: Oceans and Coastal Ecosystems and Their Services. In: Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 379–550, doi:10.1017/9781009325844.005.
- ISSN 1752-0908.
- doi:10.1130/G32230.1.
- .
- ^ Life in the Sea Found Its Fate in a Paroxysm of Extinction New York Times, April 30, 2012.
- PMID 18577506.
- ^ PMID 22428027.
- ^ PMID 30417118.
- ^ Ritter, Karl (8 December 2010). −goal-coral-reefs.html "Climate goal may spell end for some coral reefs". Associated Press.[permanent dead link]
- ^ Markey, Sean (16 May 2006). "Global Warming Has Devastating Effect on Coral Reefs, Study Shows". National Geographic News. Archived from the original on 14 June 2006.
- S2CID 85935124.
- ^ PMID 19474044.
- PMID 29672529.
- S2CID 17105410.
- ^ Christie, P. (2004). "Marine protected areas as biological successes and social failures in Southeast Asia". American Fisheries Society Symposium. 2004 (42): 155–164. Archived from the original on 16 December 2013.
- S2CID 85105416.
- ^ Stone, Gregory (January 2011). "Phoenix Rising". National Geographic Magazine.
- ^ Ewa Magiera; Sylvie Rockel (2 July 2014). "From despair to repair: Dramatic decline of Caribbean corals can be reversed". Retrieved 8 June 2015.
- ^ "Caribbean Coral Reefs - Status Report 1970-2012" (PDF). IUCN.org. 2013. Archived from the original (PDF) on 11 January 2015.
- ^ a b Walsworth, T.E.; Schindler, D.E.; Colton, M.A.; Webster, M.S.; Palumbi, S.R.; Mumby, P.J.; Essington, T.E.; Pinsky, M.L. (1 July 2019). "Management for network diversity speeds evolutionary adaptation to climate change". Nature Research. 9: 632–636.
- ^ "World Heritage List". UNESCO. Retrieved 18 December 2016.
- ^ "A biodiversity strategy for the Great Barrier Reef". Great Barrier Reef Marine Park Authority. Archived from the original on 17 March 2012. Retrieved 20 September 2013.
- ^ "Great Barrier Reef Climate Change Action Plan 2007–2012" (PDF). Townsville, Australia: Great Barrier Reef Marine Park Authority. 2007. Archived from the original (PDF) on 28 February 2016. Retrieved 16 March 2012.
- S2CID 83619557.
- Earth Observatory. Archived from the originalon 11 October 2006. Retrieved 2 November 2006.
- S2CID 206533178. Archived from the original(PDF) on 9 October 2022. Retrieved 1 November 2013.
- ^ Mallikarjun, Y. (10 December 2014). "Satellites to assess coral reef health". The Hindu. Retrieved 13 December 2014.
- ^ "Coral Restoration". Shark Research & Conservation Program (SRC). University of Miami. Retrieved 3 May 2020.
- .
- .
- PMID 18829052. Archived from the original(PDF) on 23 May 2013.
- S2CID 83723761.
- ^ PMID 27781176.
- ISSN 1526-100X.
- ^ "The game-changing robotics helping to grow new corals". Great Barrier Reef Foundation. 9 January 2023. Retrieved 19 January 2024.
- ^ S2CID 146076500.
- ^ "Gene Therapy Could Help Corals Survive Climate Change". Scientific American. 29 February 2012.
- ^ PMID 25646461.
- .
- ^ PMID 11320228.
- ^ PMID 11274358.
- ISSN 0888-8892.
- ISSN 0022-0981.
- ^ ISSN 0925-8574.
Further references
- Coral Reef Protection: What Are Coral Reefs?. US EPA.
- UNEP. 2004. Coral Reefs in the South China Sea. UNEP/GEF/SCS Technical Publication No. 2.
- UNEP. 2007. Coral Reefs Demonstration Sites in the South China Sea. UNEP/GEF/SCS Technical Publication No. 5.
- UNEP, 2007. National Reports on Coral Reefs in the Coastal Waters of the South China Sea. UNEP/GEF/SCS Technical Publication No. 11.
External links
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Coral Reefs: Rainforests of the Sea ORG Educational films. |
- "Coral Reef Factsheet". Waitt Institute. Archived from the original on 9 June 2015. Retrieved 8 June 2015.
- Corals and Coral Reefs overview at the Smithsonian Ocean Portal
- About Corals Archived 26 December 2013 at the Wayback Machine Australian Institute of Marine Science.
- International Coral Reef Initiative
- Moorea Coral Reef Long Term Ecological Research Site (US NSF)
- ARC Centre of Excellence for Coral Reef Studies
- NOAA's Coral-List Listserver for Coral Reef Information and News
- NOAA's Coral Reef Conservation Program
- NOAA's Coral Reef Information System
- ReefBase: A Global Information System on Coral Reefs Archived 31 August 2012 at the Wayback Machine
- National Coral Reef Institute Archived October 23, 2012, at the Wayback Machine Nova Southeastern University
- Marine Aquarium Council Archived 24 July 2013 at the Wayback Machine
- NCORE National Center for Coral Reef Research University of Miami
- Science and Management of Coral Reefs in the South China Sea and Gulf of Thailand
- Microdocs Archived 27 July 2011 at the Wayback Machine: 4 kinds of Reef Archived 24 October 2012 at the Wayback Machine & Reef structure Archived 24 October 2012 at the Wayback Machine
- Reef Relief Active Florida environmental non-profit focusing on coral reef education and protection
- Global Reef Record – Catlin Seaview Survey of reef, a database of images and other information
- "Corals and Coral Reefs" (archived). Nancy Knowlton, iBioSeminars, 2011.
- Nancy Knowlton's Seminar: "Corals and Coral Reefs". Nancy Knowlton, iBioSeminars, 2011.
- About coral reefs Living Reefs Foundation, Bermuda
- Caribbean Coral Reefs - Status Report 1970-2012 by the YouTube, featuring the report.