GCC Team Awarded NSF Grant to Assess How Salt in Freshwater Streams Impacts Aquatic Ecosystems
September 29, 2022
September 29, 2022
Headwater streams, which comprise 70% of all watersheds, are becoming more and more contaminated by salt. The seemingly innocuous compound is making its way into the streams and groundwater as a result of agriculture, mining, urbanization and wastewater discharge, leading to headwaters becoming more and more salty. This phenomenon, known as salinization, has been slowly changing the composition of the freshwater streams, and is having a detrimental effect on the resident microbes and animals which inhabit those waters. Changes to these ecosystems can alter the entire freshwater food web, which can have devastating effects on many species and less known large-scale environmental impacts.
The Appalachian region of the United States is home to extremely high biodiversity and many vulnerable headwater streams making it an urgent need to understand how increased freshwater salinization affects food webs in these environments. Sally Entrekin, associate professor in the Department of Entomology, professor Stephen Schoenholtz and associate professor Daniel McLaughlin from the Department of Forest Resources and Environmental Conservation, associate professor Erin Hotchkiss from the Department of Biological Sciences, and Carl Zipper, professor emeritus from the School of Plant and Environmental Sciences, have recently been awarded a $700,000 National Science Foundation (NSF) grant to investigate how changes in salinity from mining could impact aquatic food webs. As affiliates of the Global Change Center and the GCC Freshwater Salinization Working Group, the team was initially funded by a GCC seed grant that supported the development of this three-year study where they will expand their collaboration with local educators and scientists in the mining region.
“Our team is excited to have the opportunity to figure out how salinized headwaters could result in change to carbon cycling through altered food web energetics”, said Entrekin.
The team’s research will focus on streams in the Appalachian Mountains, where surface coal mining covers about 2,200 square miles of the region, and has resulted in accelerated leaching of salts into the headwater streams leading to changes in organisms and likely their functions. These man-made environmental changes threaten the region’s aquatic ecosystems, which are home to more than 10,000 species of microbes and animals. Many of the animals living in these habitats exist only in this region, and collectively these environments feature some of the most diverse aquatic insect communities in the world. The water-borne organisms make up a complex food web that transform and transfer carbon and other nutrients from the surrounding forest, and are crucial to the breakdown of plant materials. Increases in the salt concentration threatens to make these ecosystems uninhabitable for many of the native microorganisms, insects, and other animals that could destabilize the food web, and indirectly affect the survival of other species. This vital research will help to assess the damage that an increase in freshwater salt concentration may cause, and could be a first step in preventing cascading failures of crucial aquatic habitats.
- Written by James Mason