Study Shows Freshwater Lakes Increasingly Polluted by Salt

Salt pollution in freshwater ecosystems is increasing worldwide, and existing water quality regulations are not doing enough to address the issue, scientists have found.

Montclair State University Assistant Professor of Biology Matthew Schuler is among a group of scientists across North America and Europe to collaborate on a study organized through the Global Lake Ecological Observatory Network (GLEON) and published in the journal Proceedings of the National Academy of Sciences.

The findings show that lake ecosystems are being negatively affected due to significant damage from salt pollution caused by the over application of road de-icing salts, improper agricultural practices and mining operations. They also suggest that ecological damage to lakes can occur “at salt concentrations below ranges government regulators have deemed safe and protective of freshwater organisms.”

Schuler was one of the original contributing designers of this study, based on multiple projects that he and collaborators completed in 2017 showing that zooplankton are being negatively affected by increased road salt pollution in different aquatic environments. To better understand the broad implications of road salt pollution, collaborating labs from around the world worked together to conduct the same experiment using different lake water and different communities of zooplankton.

If the concentration of salt in lakes continues to increase, there could be strong negative effects on freshwater environments that cascade through the entire food web, affecting every organism from phytoplankton to fish

Results from Schuler’s original research showed that zooplankton populations decline when salt concentrations increase, but the exact threshold that caused significant zooplankton decline was difficult to determine from single-site studies.

Read the full article on the University Press Room.