Base cations (Na, K, Ca, Mg) are common elements in terrestrial and aquatic ecosystems. Numerous human activities increase base cations in catchment soils and surface waters, including: irrigation waters, deicing salts, concrete dissolution (Ca), liming and fertilizers (K, Ca & Mg), acid rain depletion and recovery (Ca), surface mining (Ca), wastewater effluent (Ca, Na), and flooding and salt water intrusion (Na). Large increases in total salt concentration (salinity) is a known driver of aquatic biogeochemistry and ecology, as well as microbial population and community structure. The subtle effects of specific base cations at low concentrations are poorly understood. If specific base cations appreciably alter freshwater biogeochemistry and underlying microbial communities at low salinities, then they could be an unrecognized driver of ecosystems.
Base cations as drivers of microbial ecology in freshwater systems: Implications for water quality management and ecosystem resilience
The goal of this project is to determine if base cations directly alter the microbial community structure and persistence of fecal indicator bacteria in aquatic ecosystems. Using laboratory mesocosms , we will quantify the effects of individual base cations on: 1) the total microbial community structure in aquatic systems, and 2) the persistence of different populations of water quality indicator bacteria. This project is done in collaboration with Drs. Brian Badgley, Bryan Brown, and Leigh-Anne Krometis and funded by the Institute for Critical and Technology and Applied Science @ Virginia Tech.