Acidification of Polar Waters
Monday, 12. October 2009, 07:24:08
Sea butterflies, also known as flapping snails, are small swimming sea snails. Their wing-like foot allows them to swim. Some species of sea butterfly have shells composed of aragonite, a form of calcium carbonate with the same chemical formula as calcite, CaCO3, but with another crystal shape. These snails play a key role in the cycling of carbon and carbonate, and are considered sentinels for environmental change, even though they can survive for a couple of days in water depleted of calcium carbonate, their shells already begin to show dissolution marks.
Since they have an aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of man made carbon dioxide (CO2) emissions. (The oceans have absorbed about one third of total man made CO2 emissions since 1800. Although this uptake of greenhouse gases limits global warming, it also causes profound changes in the chemistry of sea-water such as a decrease of pH referred to as “ocean acidification”.) The only shelled sea butterfly in Arctic waters is Limacina helicina, a species that can occur in high densities in both the Arctic and the Southern Ocean. Comeau et al. have collected Limacina helicina from Kongsfjorden, Svalbard, to study their response to the acidification of polar waters that has been predicted will occur as atmospheric CO2 increases, carbonate declines, and ice melt.
Kongsfjorden
The impact of changes in the carbonate chemistry was investigated on Limacina helicina. The snails were kept in culture under controlled pH conditions corresponding to pCO2 levels of 350 and 760 μatm. Calcification was estimated using a fluorochrome (a fluorescent substances used in fluorescence microscopy to stain specimens) and the radioisotope 45Ca. It exhibits a 28% decrease at the pH value expected for 2100 compared to the present pH value. This result supports the concern for the future of sea butterflies in a high-CO2 world, as well as of those species dependent upon them as a food resource. A decline of their populations would likely cause dramatic changes to the structure, function and services of polar ecosystems.
The results of this study support the concern for the future of sea butterflies in a high-CO2 world, as well as of those species dependent upon them as a food resource. A decline of their populations would likely cause dramatic changes to the structure, function and services of polar ecosystems. In fact it has been said that sea butterflies might be at risk to climate change and their demise would be “catastrophic” to the ocean food chain.
The study was published in Biogeosciences. Biogeosciences is an Open Access Journal (with Peer-Review) under a Creative Commons License. This means that you can download the full article as pdf-file for free. Thank you!.
Reference:
Comeau et al.
Impact of ocean acidification on a key Arctic pelagic mollusc (Limacina helicina),
Biogeosciences, 6, 1877-1882, 2009.
Since they have an aragonitic shell, they could be very sensitive to ocean acidification driven by the increase of man made carbon dioxide (CO2) emissions. (The oceans have absorbed about one third of total man made CO2 emissions since 1800. Although this uptake of greenhouse gases limits global warming, it also causes profound changes in the chemistry of sea-water such as a decrease of pH referred to as “ocean acidification”.) The only shelled sea butterfly in Arctic waters is Limacina helicina, a species that can occur in high densities in both the Arctic and the Southern Ocean. Comeau et al. have collected Limacina helicina from Kongsfjorden, Svalbard, to study their response to the acidification of polar waters that has been predicted will occur as atmospheric CO2 increases, carbonate declines, and ice melt.Kongsfjorden
The impact of changes in the carbonate chemistry was investigated on Limacina helicina. The snails were kept in culture under controlled pH conditions corresponding to pCO2 levels of 350 and 760 μatm. Calcification was estimated using a fluorochrome (a fluorescent substances used in fluorescence microscopy to stain specimens) and the radioisotope 45Ca. It exhibits a 28% decrease at the pH value expected for 2100 compared to the present pH value. This result supports the concern for the future of sea butterflies in a high-CO2 world, as well as of those species dependent upon them as a food resource. A decline of their populations would likely cause dramatic changes to the structure, function and services of polar ecosystems.The results of this study support the concern for the future of sea butterflies in a high-CO2 world, as well as of those species dependent upon them as a food resource. A decline of their populations would likely cause dramatic changes to the structure, function and services of polar ecosystems. In fact it has been said that sea butterflies might be at risk to climate change and their demise would be “catastrophic” to the ocean food chain.
The study was published in Biogeosciences. Biogeosciences is an Open Access Journal (with Peer-Review) under a Creative Commons License. This means that you can download the full article as pdf-file for free. Thank you!.
Reference:
Comeau et al.
Impact of ocean acidification on a key Arctic pelagic mollusc (Limacina helicina),
Biogeosciences, 6, 1877-1882, 2009.
-
http://www.biogeosciences.net/6/1877/2009/bg-6-1877-2009.html
-
http://oceanacidification.wordpress.com/2008/02/20/loss-of-pteropods-might-be-catastrophic/
WIDGETIZE