Ocean acidification in the Great Barrier Reef

Last updated

Ocean acidification threatens the Great Barrier Reef by reducing the viability and strength of coral reefs. The Great Barrier Reef, considered one of the seven natural wonders of the world and a biodiversity hotspot, is located in Australia. Similar to other coral reefs, it is experiencing degradation due to ocean acidification. Ocean acidification results from a rise in atmospheric carbon dioxide, which is taken up by the ocean. [1] [2] This process can increase sea surface temperature, decrease aragonite, and lower the pH of the ocean. The more humanity consumes fossil fuels, the more the ocean absorbs released CO₂, furthering ocean acidification.

Contents

This decreased health of coral reefs, particularly the Great Barrier Reef, can result in reduced biodiversity. Organisms can become stressed due to ocean acidification and the disappearance of healthy coral reefs, such as the Great Barrier Reef, is a loss of habitat for several taxa. Ocean acidification makes it harder for organisms to reproduce affecting the ecosystem in the Great Barrier Reef.

Species of fish can be affected immensely from ocean acidification which disrupts the overall ecosystem. There is a possible solution that can reverse the effects of ocean acidification called alkalization injection. Alkalization injection injects a solution into the ocean and increases the pH of the water. Coral reefs are very important to society and the economy.

Map of the Great Barrier Reef Map of Great Barrier Reef Demis.png
Map of the Great Barrier Reef

Background

Atmospheric carbon dioxide has risen from 280 to 409 ppm [3] since the industrial revolution. [4] Around 30% of carbon dioxide released from humans have been absorbed into the ocean during that era. [5] This increase in carbon dioxide has led to a 0.1 decrease in pH, and it could decrease by 0.5 by 2100. [6] [7] When carbon dioxide meets seawater, it forms carbonic acid; the molecules dissociate into hydrogen, bicarbonate, and carbonate, and they lower the pH of the ocean. [8] Sea surface temperature, ocean acidity, and dissolved inorganic carbon are also positively correlated with atmospheric carbon dioxide. [9] Ocean acidification can cause hypercapnia and increase stress in marine organisms, thereby leading to decreased biodiversity. [4] Coral reefs themselves can also be negatively affected by ocean acidification, as calcification rates decrease and acidity increases. [10]

Aragonite is impacted by the process of ocean acidification because it is a form of calcium carbonate. [8] It is essential in coral viability and health because it is found in coral skeletons and is more readily soluble than calcite. [8] Increasing carbon dioxide levels can reduce coral growth rates from 9 to 56% due to the lack of available carbonate ions needed for the calcification process. [10] [11] Other calcifying organisms, such as bivalves and gastropods, experience negative effects due to ocean acidification as well. [10] The excess hydrogen ions in the acidic water dissolve their shells, limiting their shelter and reproduction rates. [12]

As a biodiversity hotspot, the many taxa of the Great Barrier Reef are threatened by ocean acidification. [13] Rare and endemic species are in greater danger due to ocean acidification, because they rely upon the Great Barrier Reef more extensively. Additionally, the risk of coral reefs collapsing due to acidification poses a threat to biodiversity. [14] The stress of ocean acidification could also negatively affect other biological processes, such as reducing photosynthesis or reproduction and allowing organisms to become vulnerable to disease. [15]

The Great Barrier Reef is susceptible to poor water quality and the impacts of ocean acidification. There are thirty five major rivers that discharge nutrient and sediment loads, there is about five to eight times the amount of discharge then prior to European settlement. These discharges lead to elevated seawater nutrients and turbidity which further promotes the impacts Ocean acidification. [16]

Coral health

Calcification and aragonite

Carbon dioxide (CO2) reacts with water to form carbonic acid (H2CO3), which dissociates into bicarbonate (HCO3-) and hydrogen ions (H+), leading to a reduction in carbonate ions (CO32-) and shell dissolution over time. Effect of Ocean Acidification on Calcification.png
Carbon dioxide (CO₂) reacts with water to form carbonic acid (H₂CO₃), which dissociates into bicarbonate (HCO₃⁻) and hydrogen ions (H⁺), leading to a reduction in carbonate ions (CO₃²⁻) and shell dissolution over time.

Coral is a calcifying organism, putting it at high risk for decay and slow growth rates as ocean acidification increases. [10] Aragonite assists the coral as they build their skeletons because it is another form of calcium carbonate (CaCO3) that is more soluble. When the pH of the water decreases, aragonite decreases as well, leading to the loss of calcium carbonate uptake in corals. [17] Levels of aragonite have decreased by 16% since industrialization and could be lower in some portions of the Great Barrier Reef due to the current, which allows northern corals to take up more aragonite than southern corals. [17] Aragonite is predicted to reduce by 0.1 by 2100 which could greatly hinder coral growth. [17] Since 1990, calcification rates of Porites, a common large reef-building coral in the Great Barrier Reef, have decreased by 14.2% annually. [10] Aragonite levels across the Great Barrier Reef itself are not equal; due to currents and circulation, some portions of the Great Barrier Reef can have half as much aragonite as others. [17] Levels of aragonite are also affected by calcification and production, which can vary from reef to reef. [17] If atmospheric carbon dioxide reaches 560 ppm, most ocean surface waters will be adversely undersaturated with respect to aragonite, and the pH will have reduced by about 0.24 units, from almost 8.2 today to just over 7.9. At this point (sometime in the third quarter of this century, at current rates of carbon dioxide increase), only a few parts of the Pacific will have levels of aragonite saturation adequate for coral growth. Additionally, if atmospheric carbon dioxide reaches 800 ppm, the ocean surface water pH decrease will be 0.4 units, and the total dissolved carbonate ion concentration will have decreased by at least 60%. [15] Recent estimates state that with business-as-usual emission levels, the atmospheric carbon dioxide could reach 800 ppm by the year 2100. [18] At this point, it is almost certain that all the reefs in the world will be in erosional states. Increasing the pH and replicating pre-industrialization ocean chemistry conditions in the Great Barrier Reef, however, led to an increase in coral growth rates of 7%. [19]

Temperature

Ocean acidification can also lead to increased sea surface temperature. An increase of about 1 or 2 °C can cause the collapse of the relationship between coral and zooxanthellae, possibly leading to bleaching. [15] The average sea surface temperature in the Great Barrier Reef is predicted to increase between 1 and 3 °C by 2100. [6] Bleaching occurs when the zooxanthellae and coralline algae leave the coral skeleton behind due to stresses in the water. This causes the coral to lose its colour because the previous organisms sustained on the coral skeleton vacate, leaving a white skeleton. The bleached coral can no longer complete photosynthesis, and so it slowly dies. The acidity of the water will slowly dissolve the leftover coral skeletons, essentially damaging the structural integrity of the coral reef. There are many organisms that also rely on the algae and zooxanthellae for their main source of food. Therefore, organisms in the bleached coral reef are forced to leave in search of new food sources. Since zooxanthellae and algae grow very slowly, restoring the coral reef to its original form will take a very long time. [20] This breakdown of the relationship between the coral and the zooxanthellae occurs when Photosystem II is damaged, either due to a reaction with the D1 protein or a lack of carbon dioxide fixation; these result in a lack of photosynthesis and can lead to bleaching. [8]

Reproduction

Ocean acidification threatens coral reproduction throughout almost all aspects of the process. Gametogenesis may be indirectly affected by coral bleaching. Additionally, the stress that acidification puts on coral can potentially harm the viability of the sperm released. Larvae can also be affected by this process; metabolism and settlement cues could be altered, changing the size of the population or viability of reproduction. [8] [2] Other species of calcifying larvae have shown reduced growth rates under ocean acidification scenarios. [9] Biofilm, a bioindicator for oceanic conditions, underwent a reduced growth rate and altered composition in acidification, possibly affecting larval settlement on the biofilm itself. [21]

Health Reports of The Great Barrier Reef

Throughout the years there have been a few mass bleaching events that have affected the Great Barrier Reef. In particular, the years of 2016 and 2017, saw the reef sustain two years of back to back bleaching periods. This long period accounted for an estimated loss of half of the coral life in the Great Barrier Reef. The parts of the reef that did survive were damaged, leading to an overall period of low coral reproduction. [22] This was later followed by another bleaching event in 2020, making it the third bleaching event in five years. Studies found however that the results of the 2020 bleaching were not too severe, as it only affected a minimal amount of reefs, with most being in the lower to moderate levels of bleaching. [23]

In early 2022 a study showed, 91% of coral in the Great Barrier Reef, have experienced some degree of coral bleaching. [24] The reefs that had higher levels of bleaching, often were accompanied by higher overall air temperature. These temperature levels lasted all through the summer season in Australia, attributing to prolonged coral bleaching periods. Prolonged periods raise concern, as corals would not be able to reproduce and die out, leading to more loss of the reefs. However, recent reports from June 2022, have stated that the Great Barrier Reef, is currently recovering. Reefs affected by bleaching have lowered to 16% along different areas of the Australian Coast. [24] As ocean temperatures continue to drop, we can expect bleaching levels to go down, and coral levels to increase. Though coral bleaching has gone down, predators of the coral reef, Crown-of-thorns starfish, are still impacting coral growth and development. [24]

Biodiversity

Biodiversity refers to the variety of life forms, including species diversity, genetic diversity, and ecosystem diversity. The Great Barrier Reef is a biodiversity hotspot, ranging over 9000 known species. [25] However, since the 1950’s half of the living corals on the Great Barrier Reef have died, and coral reef-associated biodiversity has declined by sixty three percent. [26] Only an estimated twenty five percent of these species have been formally discovered, leaving a substantial proportion yet to be scientifically classified. [26] We are no doubt losing species we have yet to identify in the wake of a shifting climate.

Reduced levels of aragonite, as a result of ocean acidification, continues to be one of the Great Barrier Reef's biggest threats. [11] Healthy reefs support thousands of different corals, fish and marine mammals, but bleached reefs lose their ability to support and sustain life. [27] Coral structural formations create complex habitats critical for providing shelter, breeding grounds, and food sources for numerous marine organisms, including fish, invertebrates, and microorganisms. [28] In turn, corals depend on reef fish and other organisms to clean and regulate algae levels, provide nutrients for coral growth, and keep pests in check. [28] Coral reefs and the species they host have dynamic symbiotic relationships.

Ocean acidification can also indirectly affect any organism, having reduced growth rates, decreased reproductive capacity, increased susceptibility to disease, and elevated mortality rates. [29] Bleaching events trigger homogenization of coral composition and losses of structural complexity which can be detrimental to reef fish and other organisms that depend on branching coral for breeding and shelter. [29] This decrease in ecosystem diversity has direct effects on species diversity.

Vulnerable Species

As coral reefs decay, their residents will have to adapt or find new habitats on which to rely. [15] Ocean acidification threatens the fundamental chemical balance of our oceans, creating conditions that eat away at essential minerals like calcium carbonate. A lack of aragonite and decreasing pH levels in ocean water makes it harder for calcifying organisms such as oysters, clams, lobsters, shrimp and coral reefs to build their shells and exoskeletons. [30] Organisms have been found to be more sensitive to the effects of ocean acidification in early, larval or planktonic stages. Larval health and settlement of both calcifying and non-calcifying organisms can be harmed by ocean acidification.

A study published in the journal Global Change Biology developed a model for predicting the vulnerability of sharks and sting rays to climate change in the Great Barrier Reef. It was found that 30 of the 133 species were identified as moderately or highly vulnerable to climate change with the most vulnerable species being the freshwater whipray, porcupine ray, speartooth shark, and sawfish. Increasing temperature is also affecting the behavior and fitness of may reef species such as the common coral trout, a very important fish in sustaining the health of coral reefs. [31] Not only can ocean acidification affect habitat and development, but it can also affect how organisms view predators and conspecifics. Studies on the effects of ocean acidification have not been performed on long enough time scales to see if organisms can adapt to these conditions. However, ocean acidification is predicted to occur at a rate that evolution cannot match. [12]

Some fish can compensate for disturbances under high CO2 conditions but they show unexpected sensitivity to current and future growing CO2 levels. The sensitivity affects many physiological and behavioral processes, including the growth to otoliths which are calcium carbonate structures in fish ears that aid in balance. Also, it affects functions in the brains, the amount of energy the fish uses, and the amount of nutrients a fish can absorb. The consequences of disrupted neurotransmitters like GABA are still being studied, but it can affect fish in the near future. Sensitivity of fish from ocean acidification varies between species with sensory perception being affected the most between all species. [32]

Crown of Thorns Sea Star

A naturally occurring predator to coral reefs in the Great Barrier Reef is the Crown of Thorns sea star (Acanthaster planci). Population outbreaks of the Crown of Thorns sea star are one of the major causes of coral decline across the Great Barrier Reef, as an adult crown-of-thorns starfish is capable of consuming up to 10 m2 of reef building coral a year. [9] However, each species of coral is not equally impacted, as the sea star has been observed to favor branching species of coral, Acropora, followed by a sub branching species. This results in a sequential and ordered eradication of coral reef species.

Crown of Thorns Sea Star outbreaks on the Great Barrier Reef have become more frequent in recent years, which scientists predict could be linked to human activities. [33] Any increase in nutrients, possibly from river run-off, can positively affect starfish populations, leading to detrimental outbreaks. [33] As pressures from climate change increase, the time between reef disturbances is becoming shorter, leaving less time for reef recovery.

Possible Solution

A simulation from 2015 has shown a potential solution that involves artificial ocean alkalization. This method contains a solution that increases the alkalinity of water by about 4 moles. Ships will inject artificial ocean alkalization throughout the coast of the ocean and it would decrease the pH of the ocean, causing ocean acidification to go away temporarily. Through the simulation, the results stated a significant increase in aragonite saturation state across the Great Barrier Reef. The use of alkalization would offset around 4 years of ocean acidification. Also, the results showed that there was an increase in aragonite saturation state in about 25% of the reefs which means that alkalization is helpful in reducing OA. [34]

Importance of Coral Reefs

Being a major hotspots of biodiversity, coral reefs are very important to the ecosystem and livelihood of marine and human life. Countries around the world depend on reefs as a source of food and income, especially for civilizations that inhabit small islands. [35] With over a 60% decrease in available fishing around coral reefs, many countries, will be forced to adapt. [25] Coral Reefs are also important for a countries economy, as reefs provide various forms of tourist activities, that can generate a lot of revenue for the economy. [36] These can also contribute to individual levels of wellness, as the owners of these business, profit off of increased visitation and usage. Coral Reefs also provide, a form of coastal infrastructure, that acts as a barrier protecting coastal communities from major ocean catastrophes, such as tsunamis and coastal storms. [35]

See also

Related Research Articles

<span class="mw-page-title-main">Coral</span> Marine invertebrates of the subphylum Anthozoa

Corals are colonial marine invertebrates within the subphylum Anthozoa of the phylum Cnidaria. They typically form compact colonies of many identical individual polyps. Coral species include the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.

<span class="mw-page-title-main">Coral reef</span> Outcrop of rock in the sea formed by the growth and deposit of stony coral skeletons

A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups.

<span class="mw-page-title-main">Coral bleaching</span> Phenomenon where coral expel algae tissue

Coral bleaching is the process when corals become white due to loss of symbiotic algae and photosynthetic pigments. This loss of pigment can be caused by various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae that live inside their tissue, causing the coral to turn white. The zooxanthellae are photosynthetic, and as the water temperature rises, they begin to produce reactive oxygen species. This is toxic to the coral, so the coral expels the zooxanthellae. Since the zooxanthellae produce the majority of coral colouration, the coral tissue becomes transparent, revealing the coral skeleton made of calcium carbonate. Most bleached corals appear bright white, but some are blue, yellow, or pink due to pigment proteins in the coral.

<span class="mw-page-title-main">Southeast Asian coral reefs</span> Marine ecosystem

Southeast Asian coral reefs have the highest levels of biodiversity for the world's marine ecosystems. They serve many functions, such as forming the livelihood for subsistence fishermen and even function as jewelry and construction materials. Corals inhabit coastal waters off of every continent except Antarctica, with an abundance of reefs residing along Southeast Asian coastline in several countries including Indonesia, the Philippines, and Thailand. Coral reefs are developed by the carbonate-based skeletons of a variety of animals and algae. Slowly and over time, the reefs build up to the surface in oceans. Coral reefs are found in shallow, warm salt water. The sunlight filters through clear water and allows microscopic organisms to live and reproduce. Coral reefs are actually composed of tiny, fragile animals known as coral polyps. Coral reefs are significantly important because of the biodiversity. Although the number of fish are decreasing, the remaining coral reefs contain more unique sea creatures. The variety of species living on a coral reef is greater than anywhere else in the world. An estimation of 70-90% of fish caught are dependent on coral reefs in Southeast Asia and reefs support over 25% of all known marine species.

<span class="mw-page-title-main">Ocean acidification</span> Decrease of pH levels in the ocean

Ocean acidification is the ongoing decrease in the pH of the Earth's ocean. Between 1950 and 2020, the average pH of the ocean surface fell from approximately 8.15 to 8.05. Carbon dioxide emissions from human activities are the primary cause of ocean acidification, with atmospheric carbon dioxide levels exceeding 422 ppm. CO2 from the atmosphere is absorbed by the oceans. This chemical reaction produces carbonic acid which dissociates into a bicarbonate ion and a hydrogen ion. The presence of free hydrogen ions lowers the pH of the ocean, increasing acidity. Marine calcifying organisms, such as mollusks and corals, are especially vulnerable because they rely on calcium carbonate to build shells and skeletons.

<span class="mw-page-title-main">Coral island</span> Island formed from coral and associated material

A coral island is a type of island formed from coral detritus and associated organic material. It occurs in tropical and sub-tropical areas, typically as part of a coral reef which has grown to cover a far larger area under the sea. The term low island can be used to distinguish such islands from high islands, which are formed through volcanic action. Low islands are formed as a result of sedimentation upon a coral reef or of the uplifting of such islands.

<span class="mw-page-title-main">Elkhorn coral</span> Species of coral

Elkhorn coral is an important reef-building coral in the Caribbean. The species has a complex structure with many branches which resemble that of elk antlers; hence, the common name. The branching structure creates habitat and shelter for many other reef species. Elkhorn coral is known to grow quickly with an average growth rate of 5 to 10 cm per year. They can reproduce both sexually and asexually, though asexual reproduction is much more common and occurs through a process called fragmentation.

<span class="mw-page-title-main">Coral Triangle</span> Ecoregion of Asia–Pacific

The Coral Triangle (CT) is a roughly triangular area in the tropical waters around Indonesia, Malaysia, Papua New Guinea, the Philippines, Solomon Islands, and Timor-Leste. This area contains at least 500 species of reef-building corals in each ecoregion. The Coral Triangle is located between the Pacific and Indian oceans and encompasses portions of two biogeographic regions: the Indonesian-Philippines Region, and the Far Southwestern Pacific Region. As one of eight major coral reef zones in the world, the Coral Triangle is recognized as a global centre of marine biodiversity and a global priority for conservation. Its biological resources make it a global hotspot of marine biodiversity. Known as the "Amazon of the seas", it covers 5.7 million square kilometres (2,200,000 sq mi) of ocean waters. It contains more than 76% of the world's shallow-water reef-building coral species, 37% of its reef fish species, 50% of its razor clam species, six out of seven of the world's sea turtle species, and the world's largest mangrove forest. The epicenter of that coral diversity is found in the Bird’s Head Seascape of Indonesian Papua, which hosts 574 species. In 2014, the Asian Development Bank (ADB) reported that the gross domestic product of the marine ecosystem in the Coral Triangle is roughly $1.2 trillion per year and provides food to over 120 million people. According to the Coral Triangle Knowledge Network, the region annually brings in about $3 billion in foreign exchange income from fisheries exports, and another $3 billion from coastal tourism revenues.

<span class="mw-page-title-main">Environmental issues with coral reefs</span> Factors which adversely affect tropical coral reefs

Human activities have substantial impact on coral reefs, contributing to their worldwide decline. Damaging activities encompass coral mining, pollution, overfishing, blast fishing, as well as the excavation of canals and access points to islands and bays. Additional threats comprise disease, destructive fishing practices, and the warming of oceans. Furthermore, the ocean's function as a carbon dioxide sink, alterations in the atmosphere, ultraviolet light, ocean acidification, viral infections, the repercussions of dust storms transporting agents to distant reefs, pollutants, and algal blooms represent some of the factors exerting influence on coral reefs. Importantly, the jeopardy faced by coral reefs extends far beyond coastal regions. The ramifications of climate change, notably global warming, induce an elevation in ocean temperatures that triggers coral bleaching—a potentially lethal phenomenon for coral ecosystems.

The resilience of coral reefs is the biological ability of coral reefs to recover from natural and anthropogenic disturbances such as storms and bleaching episodes. Resilience refers to the ability of biological or social systems to overcome pressures and stresses by maintaining key functions through resisting or adapting to change. Reef resistance measures how well coral reefs tolerate changes in ocean chemistry, sea level, and sea surface temperature. Reef resistance and resilience are important factors in coral reef recovery from the effects of ocean acidification. Natural reef resilience can be used as a recovery model for coral reefs and an opportunity for management in marine protected areas (MPAs).

<span class="mw-page-title-main">Effects of climate change on oceans</span>

There are many effects of climate change on oceans. One of the most important is an increase in ocean temperatures. More frequent marine heatwaves are linked to this. The rising temperature contributes to a rise in sea levels due to the expansion of water as it warms and the melting of ice sheets on land. Other effects on oceans include sea ice decline, reducing pH values and oxygen levels, as well as increased ocean stratification. All this can lead to changes of ocean currents, for example a weakening of the Atlantic meridional overturning circulation (AMOC). The main cause of these changes are the emissions of greenhouse gases from human activities, mainly burning of fossil fuels and deforestation. Carbon dioxide and methane are examples of greenhouse gases. The additional greenhouse effect leads to ocean warming because the ocean takes up most of the additional heat in the climate system. The ocean also absorbs some of the extra carbon dioxide that is in the atmosphere. This causes the pH value of the seawater to drop. Scientists estimate that the ocean absorbs about 25% of all human-caused CO2 emissions.

<span class="mw-page-title-main">Shell growth in estuaries</span>

Shell growth in estuaries is an aspect of marine biology that has attracted a number of scientific research studies. Many groups of marine organisms produce calcified exoskeletons, commonly known as shells, hard calcium carbonate structures which the organisms rely on for various specialized structural and defensive purposes. The rate at which these shells form is greatly influenced by physical and chemical characteristics of the water in which these organisms live. Estuaries are dynamic habitats which expose their inhabitants to a wide array of rapidly changing physical conditions, exaggerating the differences in physical and chemical properties of the water.

Estuarine acidification happens when the pH balance of water in coastal marine ecosystems, specifically those of estuaries, decreases. Water, generally considered neutral on the pH scale, normally perfectly balanced between alkalinity and acidity. While ocean acidification occurs due to the ongoing decrease in the pH of the Earth's oceans, caused by the absorption of carbon dioxide (CO2) from the atmosphere, pH change in estuaries is more complicated than in the open ocean due to direct impacts from land run-off, human impact, and coastal current dynamics. In the ocean, wave and wind movement allows carbon dioxide (CO2) to mixes with water (H2O) forming carbonic acid (H2CO3). Through wave motion this chemical bond is mixed up, allowing for the further break of the bond, eventually becoming carbonate (CO3) which is basic and helps form shells for ocean creatures, and two hydron molecules. This creates the potential for acidic threat since hydron ions readily bond with any Lewis Structure to form an acidic bond. This is referred to as an oxidation-reduction reaction.

<span class="mw-page-title-main">Mesophotic coral reef</span> Marine ecosystem

A mesophotic coral reef or mesophotic coral ecosystem (MCE), originally from the Latin word meso (meaning middle) and photic (meaning light), is characterized by the presence of both light-dependent coral and algae, and organisms that can be found in water with low light penetration. Mesophotic coral ecosystems occur at depths beyond those typically associated with coral reefs as the mesophotic ranges from brightly lit to some areas where light does not reach. Mesophotic coral ecosystem (MCEs) is a new, widely adopted term used to refer to mesophotic coral reefs, as opposed to other similar terms like "deep coral reef communities" and "twilight zone", since those terms sometimes are confused due to their unclear, interchangeable nature. Many species of fish and corals are endemic to the MCEs making these ecosystems a crucial component in maintaining global diversity. Recently, there has been increased focus on the MCEs as these reefs are a crucial part of the coral reef systems serving as a potential refuge area for shallow coral reef taxa such as coral and sponges. Advances in recent technologies such as remotely operated underwater vehicles (ROVs) and autonomous underwater vehicles (AUVs) have enabled humans to conduct further research on these ecosystems and monitor these marine environments.

<span class="mw-page-title-main">Marine biogenic calcification</span> Shell formation mechanism

Marine biogenic calcification is the production of calcium carbonate by organisms in the global ocean.

<span class="mw-page-title-main">Justin B. Ries</span> American marine scientist

Justin Baker Ries is an American marine scientist, best known for his contributions to ocean acidification, carbon sequestration, and biomineralization research.

<span class="mw-page-title-main">Ocean acidification in the Arctic Ocean</span> Aspect of climate change

The Arctic Ocean covers an area of 14,056,000 square kilometers, and supports a diverse and important socioeconomic food web of organisms, despite its average water temperature being 32 degrees Fahrenheit. Over the last three decades, the Arctic Ocean has experienced drastic changes due to climate change. One of the changes is in the acidity levels of the ocean, which have been consistently increasing at twice the rate of the Pacific and Atlantic oceans. Arctic Ocean acidification is a result of feedback from climate system mechanisms, and is having negative impacts on Arctic Ocean ecosystems and the organisms that live within them.

The poleward migration of coral species refers to the phenomenon brought on by rising sea temperatures, wherein corals are colonising cooler climates in an attempt to circumvent coral bleaching, rising sea levels and ocean acidification. In the age of Anthropocene, the changing global climate has disrupted fundamental natural processes and brought about observable changes in the submarine sphere. Whilst coral reefs are bleaching in tropical areas like the Great Barrier Reef, even more striking, and perhaps more alarming; is the growth of tropical coral species in temperate regions, which has taken place over the past decade. Coral reefs are frequently compared to the "canaries in the coal mine," who were used by miners as an indicator of air quality. In much the same way, "coral reefs are sensitive to environmental changes that could damage other habitats in the future," meaning they will be the first to visually exhibit the true implications of global warming on the natural world.

<span class="mw-page-title-main">Human impact on marine life</span>

Human activities affect marine life and marine habitats through overfishing, habitat loss, the introduction of invasive species, ocean pollution, ocean acidification and ocean warming. These impact marine ecosystems and food webs and may result in consequences as yet unrecognised for the biodiversity and continuation of marine life forms.

<span class="mw-page-title-main">Particulate inorganic carbon</span>

Particulate inorganic carbon (PIC) can be contrasted with dissolved inorganic carbon (DIC), the other form of inorganic carbon found in the ocean. These distinctions are important in chemical oceanography. Particulate inorganic carbon is sometimes called suspended inorganic carbon. In operational terms, it is defined as the inorganic carbon in particulate form that is too large to pass through the filter used to separate dissolved inorganic carbon.

References

  1. ↑ Barnard, Nicola (2014). Scientific synthesis of the impacts of ocean acidification on marine biodiversity. Montreal: Secretariat of the Convention on Biological Diversity. ISBN   9789292251680.
  2. 1 2 Hall-Spencer, Jason M.; Thorndyke, Mike; Dupont, Sam (2015). "Impact of Ocean Acidification on Marine Organisms—Unifying Principles and New Paradigms". Water. 7 (10): 5592–5598. doi: 10.3390/w7105592 . hdl: 10026.1/3897 . ISSN   2073-4441.
  3. ↑ Mauna Loa Observatory, Hawaii (NOAA)
  4. 1 2 Widdecombe, S; Spicer, J. I. (2008). "Predicting the impact of ocean acidification on benthic biodiversity: what can animal physiology tell us?". Journal of Experimental Marine Biology and Ecology. 366 (1): 187–197. Bibcode:2008JEMBE.366..187W. doi:10.1016/j.jembe.2008.07.024 . Retrieved 7 July 2016.
  5. ↑ Iida, Yosuke; Takatani, Yusuke; Kojima, Atsushi; Ishii, Masao (1 April 2021). "Global trends of ocean CO2 sink and ocean acidification: an observation-based reconstruction of surface ocean inorganic carbon variables". Journal of Oceanography. 77 (2): 323–358. doi:10.1007/s10872-020-00571-5. ISSN   1573-868X.
  6. 1 2 Lough, Janice (2007). Climate and climate change on the Great Barrier Reef.
  7. ↑ Dodd, L. F.; Grabowski, J. H.; Piehler, M. F.; Westfield, I.; Ries, Justin B. (2020). "Juvenile Eastern Oysters More Resilient to Extreme Ocean Acidification than Their Mud Crab Predators". Geochemistry, Geophysics, Geosystems. 22 (2). doi:10.1029/2020gc009180. ISSN   1525-2027.
  8. 1 2 3 4 5 Lloyd, Alicia Jane (2013). "Assessing the risk of ocean acidification for scleractinian corals on the Great Barrier Reef". Doctoral Dissertation: The University of Technology Sydney. Bibcode:2013PhDT.......419L.
  9. 1 2 3 Uthicke, S; Pecorino, D (2013). "Impacts of ocean acidification on early life-history stages and settlement of the coral-eating sea star Acanthaster planci". PLOS ONE. 8 (12): e82938. Bibcode:2013PLoSO...882938U. doi: 10.1371/journal.pone.0082938 . PMC   3865153 . PMID   24358240.
  10. 1 2 3 4 5 De'ath, G; Lough, J. M. (2009). "Declining coral calcification on the Great Barrier Reef" (PDF). Science. 323 (5910): 116–9. Bibcode:2009Sci...323..116D. doi:10.1126/science.1165283. PMID   19119230. S2CID   206515977.
  11. 1 2 Kroeker, Kristy J.; Kordas, Rebecca L.; Crim, Ryan; Hendriks, Iris E.; Ramajo, Laura; Singh, Gerald S.; Duarte, Carlos M.; Gattuso, Jean-Pierre (June 2013). "Impacts of ocean acidification on marine organisms: quantifying sensitivities and interaction with warming". Global Change Biology. 19 (6): 1884–1896. Bibcode:2013GCBio..19.1884K. doi:10.1111/gcb.12179. ISSN   1354-1013. PMC   3664023 . PMID   23505245.
  12. 1 2 Gattuso, Jean-Pierre (2011). Ocean acidification: Background and history.
  13. ↑ Fabricius, K. E.; De'ath, G (2001). Oceanographic Processes of Coral Reefs, Physical and Biological Links in the Great Barrier Reef (PDF). pp. 127–144.
  14. ↑ Chin, A; Kyne, P. M. (2010). "An integrated risk assessment for climate change: analyzing the vulnerability of sharks and rays on Australia's Great Barrier Reef". Global Change Biology. 16 (7): 1936–1953. Bibcode:2010GCBio..16.1936C. doi:10.1111/j.1365-2486.2009.02128.x. S2CID   86718267.
  15. 1 2 3 4 Veron, J. E. N.; Hoegh-Guldberg, O (2009). "The coral reef crisis: The critical importance of <350ppm CO2". Marine Pollution Bulletin. 58 (10): 1428–1436. Bibcode:2009MarPB..58.1428V. doi: 10.1016/j.marpolbul.2009.09.009 . PMID   19782832.
  16. ↑ Smith, Joy N.; Mongin, Mathieu; Thompson, Angus; Jonker, Michelle J.; De'ath, Glenn; Fabricius, Katharina E. (April 2020). "Shifts in coralline algae, macroalgae, and coral juveniles in the Great Barrier Reef associated with present-day ocean acidification". Global Change Biology. 26 (4): 2149–2160. doi:10.1111/gcb.14985. ISSN   1354-1013.
  17. 1 2 3 4 5 Mongin, M; Baird, M. E. (2016). "The exposure of the Great Barrier Reef to ocean acidification". Nature Communications. 7: 10732. Bibcode:2016NatCo...710732M. doi:10.1038/ncomms10732. PMC   4766391 . PMID   26907171.
  18. ↑ FEELY, RICHARD A.; DONEY, SCOTT C.; COOLEY, SARAH R. (2009). "Ocean Acidification: Present Conditions and Future Changes in a High-CO₂ World". Oceanography. 22 (4): 36–47. doi: 10.5670/oceanog.2009.95 . hdl: 1912/3180 . ISSN   1042-8275. JSTOR   24861022.
  19. ↑ Tollefson, J (February 2016). "Landmark experiment confirms ocean acidification's toll on Great Barrier Reef". Nature. doi:10.1038/nature.2016.19410. S2CID   130069543.
  20. ↑ "Coral Bleaching | AIMS". www.aims.gov.au. Retrieved 2 March 2022.
  21. ↑ Witt, V; Wild, C (2011). "Effects of ocean acidification on microbial community composition of, and oxygen fluxes through, biofilms from the Great Barrier Reef". Environmental Microbiology. 13 (11): 2976–2989. Bibcode:2011EnvMi..13.2976W. doi:10.1111/j.1462-2920.2011.02571.x. PMID   21906222.
  22. ↑ Sommer, Lauren (26 March 2022). "Australia's Great Barrier Reef is hit with mass coral bleaching yet again". NPR. Retrieved 23 August 2022.
  23. ↑ Emslie, Mike (2020–2021). "Long-Term Monitoring Program Annual Summary Report of Coral Reef Condition 2020/2021".
  24. 1 2 3 "Reef health". www.gbrmpa.gov.au. Retrieved 23 August 2022.
  25. 1 2 Weisbrod, Katelyn (17 September 2021). "Big Reefs in Big Trouble: New Research Tracks a 50 Percent Decline in Living Coral Since the 1950s". Inside Climate News. Retrieved 23 August 2022.
  26. 1 2 Richards, Zoe T.; Day, Jon C. (8 May 2018). "Biodiversity of the Great Barrier Reef—how adequately is it protected?". PeerJ. 6: e4747. doi: 10.7717/peerj.4747 . ISSN   2167-8359. PMC   5947040 . PMID   29761059.
  27. ↑ Eddy, Tyler D.; Lam, Vicky W.Y.; Reygondeau, Gabriel; Cisneros-Montemayor, Andrés M.; Greer, Krista; Palomares, Maria Lourdes D.; Bruno, John F.; Ota, Yoshitaka; Cheung, William W.L. (September 2021). "Global decline in capacity of coral reefs to provide ecosystem services". One Earth. 4 (9): 1278–1285. Bibcode:2021OEart...4.1278E. doi: 10.1016/j.oneear.2021.08.016 . ISSN   2590-3322.
  28. 1 2 Graham, Nicholas A. J.; Wilson, Shaun K.; Jennings, Simon; Polunin, Nicholas V. C.; Bijoux, Jude P.; Robinson, Jan (30 May 2006). "Dynamic fragility of oceanic coral reef ecosystems". Proceedings of the National Academy of Sciences. 103 (22): 8425–8429. Bibcode:2006PNAS..103.8425G. doi: 10.1073/pnas.0600693103 . ISSN   0027-8424. PMC   1482508 . PMID   16709673.
  29. 1 2 Hill, Tessa S.; Hoogenboom, Mia O. (1 December 2022). "The indirect effects of ocean acidification on corals and coral communities". Coral Reefs. 41 (6): 1557–1583. doi: 10.1007/s00338-022-02286-z . ISSN   1432-0975.
  30. ↑ Cornwall, Christopher; Comeau, Steeve; Harvey, Ben (4 September 2023). "Physiological and ecological tipping points caused by ocean acidification". Earth System Dynamics Discussions. 15 (3): 671–687. doi: 10.5194/esd-2023-24 .
  31. ↑ Johansen, J. L. (2014). "Increasing ocean temperatures reduce activity patterns of a large commercially important coral reef fish". Global Change Biology. 20 (4): 1067–1074. Bibcode:2014GCBio..20.1067J. doi: 10.1111/gcb.12452 . PMID   24277276. S2CID   32063100.
  32. ↑ Doney, Scott C.; Busch, D. Shallin; Cooley, Sarah R.; Kroeker, Kristy J. (17 October 2020). "The Impacts of Ocean Acidification on Marine Ecosystems and Reliant Human Communities". Annual Review of Environment and Resources. 45 (1): 83–112. doi: 10.1146/annurev-environ-012320-083019 . ISSN   1543-5938.
  33. 1 2 Brodie, Jon; Fabricius, Katharina; De’ath, Glenn; Okaji, Ken (1 January 2005). "Are increased nutrient inputs responsible for more outbreaks of crown-of-thorns starfish? An appraisal of the evidence". Marine Pollution Bulletin. Catchment to Reef: Water Quality Issues in the Great Barrier Reef Region. 51 (1): 266–278. Bibcode:2005MarPB..51..266B. doi:10.1016/j.marpolbul.2004.10.035. ISSN   0025-326X. PMID   15757727.
  34. ↑ Mongin, Mathieu; Baird, Mark E; Lenton, Andrew; Neill, Craig; Akl, John (1 June 2021). "Reversing ocean acidification along the Great Barrier Reef using alkalinity injection". Environmental Research Letters. 16 (6): 064068. doi: 10.1088/1748-9326/ac002d . ISSN   1748-9326.
  35. 1 2 "Basic Information about Coral Reefs". www.epa.gov. 30 January 2017. Retrieved 23 August 2022.
  36. ↑ Beltran, Carmenza Duque; Camacho, Edisson Tello (28 March 2018), Beltran, Carmenza Duque; Camacho, Edisson Tello (eds.), "Introductory Chapter: Introduction to Corals in a Changing World", Corals in a Changing World, InTech, doi: 10.5772/intechopen.73868 , ISBN   978-953-51-3909-6 , retrieved 10 February 2024
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.