Read the full story at The Conversation.
Every winter, local governments across the United States apply millions of tons of road saltto keep streets navigable during snow and ice storms. Runoff from melting snow carries road salt into streams and lakes, and causes many bodies of water to have extraordinarily high salinity.
At Rensselaer Polytechnic Institute, my colleague Rick Relyea and his lab are working to quantify how increases in salinity affect ecosystems. Not surprisingly, they have found that high salinity has negative impacts on many species. They have also discovered that some species have the ability to cope with these increases in salinity.
But this ability comes at a price. In a recent study, Rick and I analyzed how a common species of zooplankton, Daphnia pulex, adapts to increasing levels of road salt. We found that this exposure affected an important biological rhythm: The circadian clock, which may govern Daphnia‘s feeding and predation avoidance behaviors. Since many fish prey on Daphnia, this effect could have ripples throughout entire ecosystems. Our work also raises questions about whether salt, or other environmental pollutants, could have similar impacts on the human circadian clock.