Agenda

Katrine Borgå, Aquatic Biology and Toxicology, Department of Biosciences, University of Oslo, Norway

Abstract:
Climate change and environmental pollutants are two threats of a healthy environment that both are imposed by human activity. In the Arctic, the two meets and affect the ecosystems there in various degrees. The presentation will give examples of pollutants movement to the Arctic, within and between food webs, and how this is affected by climate change.

In particular, the driving factors of seasonality in Arctic marine food web contaminant concentrations will be explored combining empirical and modeling approaches. The results indicate that lipid is not the only important ecological driver of seasonal contaminant accumulation (as previously hypothesised for the Barents Sea), but also food web relations and diet composition (as previously hypothesised for the Arctic). In the future Arctic climate a century ahead, simulated bioaccumulation metrics were only marginally higher than at present. Thus, results show that seasonal variation in bioaccumulation is greater than alteration as a response to predicted climate change. As the best fit seasonal scenario included the annual cycle in lipid content and trophic relations, these physiological and ecological factors are crucial for making sound predictions of contaminant food web bioaccumulation for the future. Changes in abiotic drivers alone are not sufficient to explain food web bioaccumulation on a temporal scale.

In addition, examples will be given on our projects of contaminant food web bioaccumulation in light of migration, flux of energy, dissolved organic carbon, maternal transfer.