Nutrient cocktail in coastal zones of the Baltic Sea – improving understanding of the transformation and retention of nutrients and organic matter in the coastal zone

Jacob Carstensen
Project coordinator: Jacob Carstensen, Aarhus University, Denmark

Total budget: EUR 4.0 million

Duration: 4 years, 1.1.2014-31.12.2017 

BONUS COCOA will analyse the pathways of nutrients in the coastal zones of the Baltic Sea by 1) quantifying the role of bacteria, phytoplankton, benthic microalgae, seagrasses, macroalgae and fauna in transforming and accumulating nutrients using novel measurement techniques employed in four different types of coastal ecosystems (learning sites: lagoons, river-dominated estuaries, embayments, and archipelagos), 2) developing dynamic state-of-the-art coastal models for these learning sites with a strong focus on quantifying benthic-pelagic coupling and integrating the improved process understanding to the ecosystem level, 3) developing empirical models to estimate the nutrient retention across coastal ecosystems, 4) improving the model formulations for coastal nutrient retention in the decision support system NEST, used for the revision of the Baltic Sea Action Plan. Through model experiments, BONUS COCOA will investigate feedback processes, associated with hypoxia and loss of key biological functions, and examine the potential existence of alternative stable states leading to hysteresis responses and identify critical thresholds associated with such responses. BONUS COCOA will use models and statistical analyses to examine changes in nutrient retention over the past and in the future given scenarios for climate change and management responses. Consequences of altered nutrient pathways on coastal ecosystem services will be assessed and used for identifying optimal management strategies.  

Key words
: Coastal biogeochemical models, ecosystem recovery, ecosystem services, habitat diversity, nutrient retention and transformation processes

Partners: Denmark, Finland, Germany, Lithuania, Netherlands, Poland, Russia, Sweden

Summaries of annual reports:
BONUS COCOA year 1 report

Introductory article: see BONUS in Brief December 2013

For more information visit BONUS COCOA's website and the BONUS projects' website.