CENTURION - Cumulative effects of climate change and eutrophication on Swedish lakes

Aquatic ecosystems face tremendous changes due to a multitude of stressors, among which ongoing climate change and cultural eutrophication are major large-scale drivers of ecological change, resulting in degraded ecological states and potential loss of ecological services. Stressors are expected to exert complex interactive effects, but interactions among multiple stressors cannot be easily modelled because they often generate impacts that either exceed (i.e. synergism) or fall below (i.e. antagonism) their expected additive effects. Further, the number and types of combinations of stressors affecting aquatic ecosystems has dramatically increased during the last two centuries, but few studies have empirically tested for their cumulative effects on lakes.

Aims

CENTURION addresses knowledge gaps on the cumulative effects of climate change and eutrophication on freshwater lakes.

Specific objectives

• Evaluate temporal patterns in aquatic biodiversity and ecological status since ca. 1850 and identify ecological hot-spots and extreme events in freshwater lakes across a latitudinal gradient in Sweden.
• Quantify ecological resilience to environmental drivers through paleolimnological reconstructions that help to understand the cumulative effects of nutrient enrichment and climate warming on ecological status of lakes across a latitudinal gradient in Sweden.
• Develop a novel assessment method for the EU´s Water Framework Directive that better quantifies ecological changes in lakes and provides relevant estimates of internal reference conditions for individual lakes and lake types.
• Inform policy makers, NGOs, the public, and scientists about changes in Swedish freshwater ecosystems.