Ocean acidification results from the dissolution of CO2 emitted by human activities. The impact on marine biodiversity has already been studied at least in the laboratory but there has been little experimentation to date on the adaptive capacity of species. Now, two projects managed by the Foundation for Research on Biodiversity (FRB) are testing species’ adaptability in the basins where lots of oysters and fish reside.
Acidity affects oysters’ resistance to diseases, according to preliminary results
In the basins of the Ifremer site in Argentina and Tahiti (French Polynesia), the broodstock and their descendants are exposed to acidification and temperature conditions corresponding to current conditions and IPCC projections for 2100 (with a pH decreased by 0.3 units and increased temperature by 3 degrees C).
The objective is to study the entire life cycle of the oyster, namely, the parents, the gametes, the larvae, and the young spat.
Negative effects related to the increase in acidity have already been observed on oysters’ ability to resist diseases.
Fish are also affected by ocean acidification
Regarding fish, basin tests at the Ifremer Brittany center were initiated in 2013 with different pH levels corresponding to the IPCC forecasts for 2050 and for 2100.
The first results show an impact particularly in the earlier level of fish maturation for lower pH, especially for females.
Acidification could thus influence the endocrine system that controls sexual maturation. Trials are continuing in 2018 on the second generation, with a laying in early March.
The project, called AiAiAi project, is carried out by Ifremer, a French organization for researching and exploring the oceans.
The predictions, therefore, are gloomy as the preliminary results of the tests revealed that ocean acidification, on which the humans’ activity contributes largely, affects directly the oysters and fish populations which showed no adaptability to the harmful conditions. All this could have a great negative impact on a larger scale and on many other marine life representatives.
Erin Vandyke, Canadian HOMESTEADING, 4 April 2018. Article.
