Marine organisms are facing a dim future in a world full of carbon dioxide

Overfishing and diseases are gradually killing marine life in many temperate estuarine regions in the world and coastal ecosystems. Scientists at the Smithsonian Institute, led by ecologist Whitman Miller of the Smithsonian Environmental Research Center in Edgewater, Md, have discovered another serious threat to these predators - The increasing level of carbon dioxide contributes to acidification of water in the seas, coastal areas and estuaries.

Their conclusions are posted on PLoS One
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For marine organisms and other organisms that have shells and calcium carbon structure, the problem arises when carbon dioxide decomposes in seawater and produces carbonic acid, which then quickly changes into carbonate ions. and bicarbonate ions in water. Increasing acidity leads to a balance of bicarbonate formation and gradually escapes carbonation. The decreasing amount of carbonate in the water means that marine organisms will have few basic blocks to produce their shells. If the water is acidic, the shells may even begin to disintegrate.

Millar said: 'Coastal and estuarine ecosystems are particularly vulnerable to domestic changes caused by elevated CO2 levels due to the shallow level of water and salt levels. reduced and low alkalinity makes them less elastic for changes in pH in the waters'.

For calcified marine organisms, CO2 acidification poses a serious challenge because these organisms may face diminishing growth rates and calcification when combined. with other environmental pressures can signal a disaster '

Egg-shaped mussels are considered particularly vulnerable to calcification because eggs produce shells made of aragonite, a crystal form of calcium carbonate that tends to erode at pH levels. low. Large mussels continue to build their shells but produce calcite, a more sustainable form of calcium carbonate. In the Miller study, the eggs of the eastern mussel (Crassostrea virginica) and the Suminoe mussel (Crassostrea ariakensis) were bred in estuarine waters, which contained four distinct CO2 collections, reflecting the Air bales from the pre-industrial era, now, are also expected to happen in the next 50 to 100 years. To test the effects of acidification, Miller monitored their development and measured the amount of calcium carbonate deposited in eggshells for more than a month.

Scientists have found a serious threat to marine organisms - an increasing level of carbon dioxide contributes to acidification of water in the seas, coastal areas and estuaries. (Photo: iStockphoto / Stephen Orsillo)

Miller and colleagues in his team also discovered that the mussels in the east experienced a 16% reduction in the shell area and a 42% reduction in calcium when the samples studied during the CO2 treatment phase at pre-industrial times were compared with those placed in the predicted level of 2100. Unexpectedly, Suminoe mussels in Asia have not changed at all in the development process. calcification.

Published results show that the effects of acidification may be associated with the evolutionary history of organisms and environmental circumstances, which suggest that predictions may be more complex than thoughts. before. 'In the Chesapeake Bay, barren clam species, overproduction and overfishing fisheries almost wipe out marine life here.' ' Ecologist Miller said: ' Whether acidification forces forces the mussel species in the east and many other species depend on them, the key clues are still clearly visible. '

"Whether acidification drives the West oyster species and many other organisms related to disappearance - this is still an open question so far," Miller said.

With an ever-decreasing number - the chesapeake mussel today is only 2% of its colonial population - future losses will have devastating consequences, both environmental and economic aspects. Indeed, the recently published Federal Oceanic Acid Study and the 2009 Surveillance Act have recognized the need to begin to determine the effects of acidification on estuaries and creatures there.

Along with the relentless outbreak of fossil fuels, the large acidification is inevitable. Miller 's team is very interested in how ecological and biological reactions will take place to better inform future and current environmental recovery efforts. Miller stated, 'In a world full of CO2, lime creatures can easily be defeated in competition with non-calcified creatures, a situation that can dramatically change the birth communities. bottom. "

Miller said: 'The urgency now is to understand how these changes occur in coastal waters or estuaries where many of the calcified organisms live and also the center of the fishing industry. trade and human activities'

The budget for this study was provided by the Seward Johnson Foundation through the Smithsonian Marine Science network as well as grants established for the Smithsonian Institution.

References:
Miller et al.Shellfish Face Uncertain Future in High CO2 World: Influence of Acidification on Oyster Larvae Calcification and Growth in Estates.PLoS ONE, 2009;4 (5): e5661 DOI: 10.1371 / journal.pone.0005661