Dr. Feely, a Senior Fellow at the NOAA Pacific Marine Environmental Laboratory in Seattle, delivered his presentation entitled 'Ocean acidification over the next 100 years: implications for marine ecosystems' to a busy Harpa Conference Centre in Reykjavík on the second day of ICES ASC, bringing to light facts about the rate of carbon uptake by bodies of salt water and projected future rates before discussing the crux of the issue for marine biologists – the effects of acidification on marine foodwebs and ecosystems.
The world's oceans have absorbed 28% of man-made carbon dioxide (C02) generated since the Industrial Revolution, acidity is up 30% (though Feely dispelled the notion that the oceans will never actually become acidic, and the term ocean acidification refers to the actual process), and the process is happening a rate almost ten times that of at any point over the last 50 million years. Ocean acidification is expected to increase 100-150% by the year 2100.
But what does this mean for the oceans and their life forms? Dr. Feely described the effects of a decreasing seawater pH on lower-level foodweb components such as bacteria and phytoplankton as well as on the presence of oxygen and rate of photosynthesis. Additionally, he detailed how the shell-building capabilities (calcification) of sea creatures such as molluscs and crustaceans may be impacted upon as the carbonate concentrations required for the process are declining. A drop in carbonate species will significantly impact food sources for humans and fish alike, as well as entire ecosystems. Feely presented several case studies – including oyster larvae in the Pacific Northwest, sea butterfly (pteropods), and pink salmon –which help to illustrate the growth-rate and physiological effects in certain species.
Following an explanation of the risks for commercial fisheries, the professor then acknowledged the scientific difficulty in predicting ecosystem response to acidification and the need for adaptation strategies, outlining three approaches: experimental evolution, breeding experiments, and new technology.
Despite progress already having been made in the development of adaption measures, more knowledge is required, and this is a key in the future conservation of organisms and systems vulnerable to acidification.
