This time Nova goes Coral picking, selecting one species of coral and ignoring the rest of the ecosystem.
Insensitive to the recent news that Australia’s Great Barrier Reef has lost 50% of its coral (not from global warming but other stresses), Nova would like you to believe that our oceans will be safe from the threat of Ocean Acidification because one species of cold water coral shows signs of Acclimation.
Nova once again confuses short term fluctuations with long term trends by mentioning that ph levels in some ecosystems can change greatly on a daily basis. She doesn’t understand that we’re not concerned by daily changes in ph levels (or temperatures) but in the long term trends that are occurring in a form that will greatly affect the ecological balance. Either that, or is she simply wants to confuse the reader.
In this study one species of coral might (the study acknowledges that “… further ecophysiological studies are necessary which should also encompass the role of food availability and rising temperatures”) adapt and actually have higher growth in a lower ph environment. But as previously discussed during the analysis of CO2Science’s Ocean Acidification studies, the growth and success of one species can be at the detriment to other species around it that are struggling with the acidified ocean.
This is a lesson repeated many times, topically demonstrated by the success of the crown of thorns starfish that has contributed greatly to the decimation of the Great Barrier Reef.
But I do agree that studies should be longer-term in order to study the effect of changing ph levels and preferably in real life, rather than in isolated aquarium tanks. In May 2011 the paper Losers and winners in coral reefs acclimatized to elevated carbon dioxide concentrations was published and amongst its findings …
Here we show that as pH declines from 8.1 to 7.8 (the change expected if atmospheric carbon dioxide concentrations increase from 390 to 750 ppm, consistent with some scenarios for the end of this century) some organisms benefit, but many more lose out. We investigated coral reefs, seagrasses and sediments that are acclimatized to low pH at three cool and shallow volcanic carbon dioxide seeps in Papua New Guinea. At reduced pH, we observed reductions in coral diversity, recruitment and abundances of structurally complex framework builders, and shifts in competitive interactions between taxa. However, coral cover remained constant between pH 8.1 and ~7.8, because massive Porites corals established dominance over structural corals, despite low rates of calcification. Reef development ceased below pH 7.7. Our empirical data from this unique field setting confirm model predictions that ocean acidification, together with temperature stress, will probably lead to severely reduced diversity, structural complexity and resilience of Indo-Pacific coral reefs within this century.