This week EEB welcomes Adam Jeziorski from the Department of Biology, Queens University:
From “Aquatic Osteoporosis” to the “Jellification of Lakes”: Ecological impacts of lakewater calcium decline on softwater boreal ecosystems
Over the past forty years, marked declines in Ca concentration have been observed in many softwater boreal lakes, and these trends are understood to be a long-term effect of acid deposition. To date, study of the direct ecological impacts of lower lakewater Ca has focused on Ca-rich members of the Cladocera, and a growing body of work suggests that reduced Ca availability can act as a potent stressor with profound consequences for aquatic ecosystems. Recent laboratory analyses and field surveys using varied approaches have provided insight into these consequences, while paleolimnological approaches have provided long-term perspective on the phenomenon. However, many questions remain regarding: (1) ‘baseline’ or ‘pre-impact’ conditions, due to the accelerated leaching of Ca from watershed soils during the acidification period, and (2) the eventual endpoints of the declines due to catchment-specific differences in both leaching rates and the initial size of the Ca pool in watershed soils. Despite these uncertainties, persistent low Ca concentrations are anticipated to impede biological recovery from lake acidification, and ongoing declines will have cascading impacts throughout aquatic ecosystems due to the loss of vulnerable taxa. To better understand how reduced Ca availability will continue to change affected surface waters and how these changes will interact with other environmental stressors will require continued multi-disciplinary investigation.
The EEB Seminars run weekly, on Thursdays, in the EEB Lounge of the BioSciences Complex, Room 4338, from 12:30-1:30pm. Light refreshments are served starting at 12:15.