Impact of melting permafrost and rock glaciers on water qualitiy and aquatic organisms in alpine lakes
Recent warming has strongly affected the melting of permafrost in high alpine regions. The melt water of permafrost and rock glaciers caused unexpected changes in aquatic ecosystems, ranging from rapid increases in conductivity to toxic levels in metal concentrations that can exceed drinking water standards by more than an order of magnitude. The processes controlling the meltwater composition, and especially metal concentrations, are not yet understood. It is, however, well known that high metal concentrations affect aquatic organisms, often causing deformations and changes in species composition. The project team investigates aquatic organisms of different trophic levels, ranging from algae (diatoms) to worms (oligochaetes), insects (chironomids, trichoptera) and fish (char and minnows), in three lakes with permafrost in the catchment. Furthermore, we will obtain short sediment cores in order to capture the historic trends of metal increase and resulting changes in species composition and toxic effects. These sediment analyses will be compared with temperature records spanning the past 220 years and with trends of atmospheric deposition based on measurements, and data from peat bogs and ice cores.
Major research questions:
· To what extent does melting permafrost affect water quality and aquatic organisms in alpine lakes? Do metals, especially nickel, released from permafrost accumulate in the food web and, if so, with what consequence?
· Is the current release of melt water from permafrost unprecedented, or do we see comparable and repeated increases in metal concentrations during warmer periods in the past?
· With ongoing warming, which hazards are to be expected for downstream ecosystems and drinking water supply when compared to the historic trends?
Co-workers: Karin A. Koinig (project leader), Elena Ilyashuk, Reinhard Lackner, Roland Psenner (all University of Innsbruck)
Investigation of mercury toxicity in landlocked char in High Arctic lakes
Objectives of this project funded by Northern Contaminants Program are
· Study the toxic effects of Hg in landlocked char in „NCP focal ecosystem“ High Arctic lakes on Cornwallis Island
· Estimate a treshold concentration of Hg associated with toxic effects in landlocked char
· Provide this information to the Hamlet of Resolute Bay (Qausuittuq) and to the Niqiit Avatittinni Committee (Nunavut) on a timely basis.
Co-workers: Paul Drevnick (project leader; University of Michigan), Benjamin Barst (Université de Montréal), Gretchen Lescord (University of New Brunswick), Karista Hudelson (INRS-ETE Université du Québec), Derek Muir (Environment Canada), Karen Kidd (University of New Brunswick), Peter Campbell and Claude Fortin (INRS-ETE, Université de Québec), Debbie Iqaluk (Resolute Bay)
Günter Köck´s Research Page