Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions
Coral reef ecosystems develop best in high-flow environments but their fragile frameworks are also vulnerable to high wave energy. Wave-resistant algal rims, predominantly made up of the crustose coralline algae (CCA) Porolithon onkodes and P. pachydermum1,2, are therefore critical structural elemen...
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ftanucanberra:oai:digitalcollections.anu.edu.au:1885/71120 2023-05-15T17:50:33+02:00 Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions Nash, Merinda Opdyke, Bradley Troitzsch, Ulrike Russell, B.D. Adey, W.H. Kato, A. Diaz-Pulido, G. Brent, Camilla Gardner, Madelene Prichard, Jennifer Kline, David 2015-12-13T22:17:25Z http://hdl.handle.net/1885/71120 unknown Nature Publishing Group 1758-678X http://hdl.handle.net/1885/71120 Nature Climate Change Journal article 2015 ftanucanberra 2015-12-28T23:35:09Z Coral reef ecosystems develop best in high-flow environments but their fragile frameworks are also vulnerable to high wave energy. Wave-resistant algal rims, predominantly made up of the crustose coralline algae (CCA) Porolithon onkodes and P. pachydermum1,2, are therefore critical structural elements for the survival of many shallow coral reefs. Concerns are growing about the susceptibility of CCA to ocean acidification because CCA Mg-calcite skeletons are more susceptible to dissolution under low pH conditions than coral aragonite skeletons3. However, the recent discovery4 of dolomite (Mg0.5 Ca0.5 (CO3)), a stable carbonate5, in P. onkodes cells necessitates a reappraisal of the impacts of ocean acidification on these CCA. Here we show, using a dissolution experiment, that dried dolomite-rich CCA have 6-10 times lower rates of dissolution than predominantly Mg-calcite CCA in both high-CO2 (∼ 700 ppm) and control (∼ 380 ppm) environments, respectively. We reveal this stabilizing mechanism to be a combination of reduced porosity due to dolomite infilling and selective dissolution of other carbonate minerals. Physical break-up proceeds by dissolution of Mg-calcite walls until the dolomitized cell eventually drops out intact. Dolomite-rich CCA frameworks are common in shallow coral reefs globally and our results suggest that it is likely that they will continue to provide protection and stability for coral reef frameworks as CO2 rises. Article in Journal/Newspaper Ocean acidification Australian National University: ANU Digital Collections |
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Australian National University: ANU Digital Collections |
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Coral reef ecosystems develop best in high-flow environments but their fragile frameworks are also vulnerable to high wave energy. Wave-resistant algal rims, predominantly made up of the crustose coralline algae (CCA) Porolithon onkodes and P. pachydermum1,2, are therefore critical structural elements for the survival of many shallow coral reefs. Concerns are growing about the susceptibility of CCA to ocean acidification because CCA Mg-calcite skeletons are more susceptible to dissolution under low pH conditions than coral aragonite skeletons3. However, the recent discovery4 of dolomite (Mg0.5 Ca0.5 (CO3)), a stable carbonate5, in P. onkodes cells necessitates a reappraisal of the impacts of ocean acidification on these CCA. Here we show, using a dissolution experiment, that dried dolomite-rich CCA have 6-10 times lower rates of dissolution than predominantly Mg-calcite CCA in both high-CO2 (∼ 700 ppm) and control (∼ 380 ppm) environments, respectively. We reveal this stabilizing mechanism to be a combination of reduced porosity due to dolomite infilling and selective dissolution of other carbonate minerals. Physical break-up proceeds by dissolution of Mg-calcite walls until the dolomitized cell eventually drops out intact. Dolomite-rich CCA frameworks are common in shallow coral reefs globally and our results suggest that it is likely that they will continue to provide protection and stability for coral reef frameworks as CO2 rises. |
format |
Article in Journal/Newspaper |
author |
Nash, Merinda Opdyke, Bradley Troitzsch, Ulrike Russell, B.D. Adey, W.H. Kato, A. Diaz-Pulido, G. Brent, Camilla Gardner, Madelene Prichard, Jennifer Kline, David |
spellingShingle |
Nash, Merinda Opdyke, Bradley Troitzsch, Ulrike Russell, B.D. Adey, W.H. Kato, A. Diaz-Pulido, G. Brent, Camilla Gardner, Madelene Prichard, Jennifer Kline, David Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
author_facet |
Nash, Merinda Opdyke, Bradley Troitzsch, Ulrike Russell, B.D. Adey, W.H. Kato, A. Diaz-Pulido, G. Brent, Camilla Gardner, Madelene Prichard, Jennifer Kline, David |
author_sort |
Nash, Merinda |
title |
Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
title_short |
Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
title_full |
Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
title_fullStr |
Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
title_full_unstemmed |
Dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
title_sort |
dolomite-rich coralline algae in reefs resist dissolution in acidified conditions |
publisher |
Nature Publishing Group |
publishDate |
2015 |
url |
http://hdl.handle.net/1885/71120 |
genre |
Ocean acidification |
genre_facet |
Ocean acidification |
op_source |
Nature Climate Change |
op_relation |
1758-678X http://hdl.handle.net/1885/71120 |
_version_ |
1766157350456000512 |