If you grew up drinking milk because you thought it was good for your bones, you know about the importance of calcium, the human body’s most plentiful mineral. But it turns out that calcium is important for the health of aquatic environment, as well.

 

A new study by Canadian researchers, published in Proceedings of the Royal Academy B, reports that calcium concentrations are decreasing in softwater lakes across North America and Western Europe, causing what the researchers call “aquatic osteoporosis.” But instead of bones, it’s the balance of nature that becomes brittle.

 

The scientists from Queen’s University found that declining calcium levels, which are caused by acid rain from air pollution and timber-harvesting that disturb forest soils and cause excessive runoff, are making it difficult for many lake-dwelling microorganisms that need the mineral to survive. Their place, in turn, is being taken by organisms that are coated with a capsule of protective jelly.