Effects of dispersal on the response of zooplankton communities to salt contamination

Thumbnail Image
Shi, Shu Hong
dispersal , chloride , salt contamination , zooplankton
The application of road de-icing salts has become associated with elevated chloride concentrations in freshwater environments. The response of ecosystems to road salt may be dependent on the spatial exchange of organisms across landscapes as the dispersal of better adapted individuals, which are functionally redundant, have the potential to buffer environmental change. My research will test the prediction that the dispersal of zooplankton with previous exposure to elevated chloride concentrations will help increase community resilience and ecosystem function of freshwater habitats without previous chloride exposure. To assess the individual and interactive effects of zooplankton dispersal and salt contamination, I conducted a mesocosm experiment with a factorial design for salt and dispersal. Cladoceran, nauplii, copepodids, copepods, and rotifers were assessed to determine exacerbating, neutral or ameliorating effects of the treatment groups. Nauplii, copepodids and copepod abundances experienced an exacerbating effect with salinity treatments, whereas rotifers were found to increase in abundance with salinity treatments and cladoceran abundance did not significantly vary with salinity treatments. Dispersal was not found to have an effect on the abundance of any of the zooplankton groups assessed. An interactive effect of salt and dispersal was found in nauplii, where nauplii in the dispersal treatment were not found to be significantly impacted by elevated chloride but were adversely affected by salt in treatments that did not receive dispersers. A greater understanding of how dispersal may impact zooplankton community responses to salt contamination is critical for understanding the variation in which freshwater communities respond to elevated chloride concentrations.
External DOI