Scientists and policymakers are working to reduce the water footprint of food production and ensure a safe ocean habitat for future supplies of fish and seafood. This month’s FutureFood 2050 series highlights thought leaders working to develop innovative solutions to help maximize use of water resources in our food chain. FutureFood 2050 is an initiative supported by the Institute of Food Technologists (IFT) that addresses how to feed the world’s expected population of more than nine billion by 2050.
One of this month’s articles showcases the work of Ulf Riebesell, a German marine biologist investigating how the unchecked pace of ocean acidification threatens to deplete future supplies of seafood and fish. He is studying how ocean acidification impacts the marine ecosystem—benefiting some and damaging others.
According to Riebesell, roughly one-third of manmade carbon dioxide (CO₂) released into the atmosphere ends up in the ocean. When dissolved in seawater, CO₂ forms carbonic acid, which in turn causes the pH levels in oceans to decline, making them more acidic. Ocean acidification has occurred before in the Earth’s history, but the current process is happening 10 times as fast as during any other period over the past 55 million years. Ocean acidity levels have jumped 26% since 1850, although such changes can’t be seen with the naked eye because CO₂ doesn’t change the color of the seawater or the fish.
Mollusks, such as oysters and mussels, are expected to be among the biggest losers from ocean acidification, according to a recent symposium summary for policymakers that Riebesell helped write. Increased acid levels in seawater reduce the concentration of carbonate ions, dissolving the shells of mollusks, which are made up of calcite and aragonite. While fish in general appear to be less sensitive to ocean acidification than other organisms, the growth rates of their larvae and their food sources may be impacted, the summary suggests, which could affect the abundance of fish in the future.
