Australia – A new study performed by marine ecologists from the University of Adelaide discovered that expected ocean acidification and climate change are increasing the risk of causing a reduction in the diversity and numbers of different species.

The research was published in the journal Proceedings of the National Academy of Sciences (PNAS), and it is the first global evaluation of marine replies to climbing human CO2 emissions which seems to have painted a grim picture of future fisheries and ocean ecosystems, according to Eurekalert.

“This ‘simplification’ of our oceans will have profound consequences for our current way of life, particularly for coastal populations and those that rely on oceans for food and trade,” says Associate Professor Ivan Nagelkerken, Australian Research Council (ARC) at the University’s Environment Institute, as Eurekalert reported.

Credit: Huffington Post

The analysis

Marine ecologists performed what is called a ‘meta-analysis’, which is a statistical technique for combining the findings from independent studies. Associate Professor Nagelkerken and marine ecologist Sean Connell, collected data from 632 extend published experiments covering tropical to arctic waters, and a range of ecosystems from coral reefs, through kelp forest to open oceans.

They found that there would be a range limit for acclimation to warmer waters and acidification. Not many species will survive from the negative effects of rising CO2. Scientists said that it is expected that various species will be reduced massively across the world, with the exception of microorganism, which are expected to expand in number and diversity.

“We know relatively little about how climate change will affect the marine environment,” says Professor Connell. “Until now, there has been almost total reliance on qualitative reviews and perspectives of potential global change. Where quantitative assessments exist, they typically focus on single stressors, single ecosystems or single species” Eurekalert reported.

The analysis presented by the University of Adelaide combines the findings of all these experiments to study the combined effects of multiple stressors on whole communities, such as species interactions and different measures of replies to climate change.

Food web point of view

Researchers claimed that the primary production from the smallest plankton is expected to rise in the warmer water but this mostly does not means secondary production, which are the zooplankton and smaller fish, which show a reduction in productivity under ocean acidification.

“With higher metabolic rates in the warmer water, and therefore a greater demand for food, there is a mismatch with less food available for carnivores — the bigger fish that fisheries industries are based around,” says Associate Professor Nagelkerken. “There will be a species collapse from the top of the food chain down.” NWR informed.

In addition, the findings demonstrated that with warmer water or raised acidification or both, there would be adverse impacts on the formation of the habitat like coral, oysters, and mussels. Any small change in the health of habitats would have a massive impact on a wide range of species these reefs harbour.

Source: Eurekalert