By Georgina Brennan, Dong Xu and Naihao Ye
Australia.- Evidence is rapidly accumulating that ocean acidification and elevated temperatures will have catastrophic consequences for marine organisms and ecosystems. In fact, it is something we are already witnessing. Coral reefs are bleaching, while snails and other calcifying marine organisms struggle to build their shells, scales and skeletons and juvenile marine animals even struggle to navigate to suitable habitats.
Yet many primary producers, including seaweeds, are predicted to thrive in the acidic oceans of the future – as they use CO2 from the seawater to produce energy by photosynthesis.
Humans have eaten seaweeds for tens of thousands of years and today the diets of billions of people, especially in Asia, are based on cultivated seaweeds. However, while future ocean conditions may improve the yield of farmed seaweeds, we do not know how the nutritional content of seaweeds will be affected by climate change. To investigate this, we recently looked into how the iodine content of seaweeds will be affected by future climate change scenarios.
Seaweeds are one of the best natural sources of iodine, and this essential mineral is used by the body to make thyroid hormones. But both too much and too little iodine can change the way the body’s thyroid gland works. If climate change were to affect the amount of iodine in seaweed, humans – and other animals – who rely on it as a staple part of their diet may suffer serious health problems.
Creating acid oceans
For this recently published study, we simulated current and future ocean acidification conditions in laboratory and outdoors settings. To conduct the outdoor experiments, we enclosed seawater in cages made of very small mesh polythene nets so that environmental conditions such as CO2 and temperature could be manipulated and responses monitored, while all other environmental conditions remained the same as the natural environment.
More information at: https://theconversation.com/ocean-acidification-will-increase-the-iodine-content-of-seaweeds-and-the-billions-of-people-who-eat-them-106568
