Since the effects of eutrophication are the result of nutrient transports and transformations in a number of different systems, management without understanding the links between the systems is likely to result in more costly mitigation programmes than necessary. Currently, our understanding of this is fragmented. There is a need to utilise and synthesise scientific information pertinent to the relevant problem and management scale. A common language for communication between scientists and managers, and a consensus about scales, problems and causes, needs to be established.

The overall goal of the MARE research programme is to develop a user-friendly, computer-based decision support system and to introduce it to managers as a tool for identifiying cost-effective strategies to counteract eutrophication of the Baltic Sea. That is the whole idea of Nest, the decision support system. It is still a prototype, but one that is continuously being further developed in collaboration between researchers and users.

Interlinked models that synthesize knowledge in ecology, physical oceanography, biogeochemistry, and economics, are used to develop this system. The objective of the MARE programme is to make it possible for decision-makers and managers working on Baltic Sea environmental issues to use the results of the calculations made in the Nest system as a basis for decisions on measures. Main target groups in this respect are decision-makers within the Helsinki Commission (HELCOM), as well as those in the Baltic Sea States working on the implementation of the EU Water Framework Directive.

Thus, the aim is to assist scientists and decision-makers in their effort to identify cost-effective measures or combinations of such measures to reduce nutrient loads and, consequently, counteract eutrophication to the Baltic Sea for the purpose of reaching the environmental targets that have been set. To be able to fulfil this goal, a decision support system needs to describe the relationship between the state of the environment and the costs for achieving a certain desired state (an environmental target). The state of the environment at different concentration levels of nitrogen and phosphrous needs to be coupled to the relationship between nutrient inputs (loads) and concentrations in the water, and finally to the costs for nutrient reductions from the most important sources of waterborne or airborne nutrients.

How to work in the decision support system, Nest? Read our user's manual.

Try yourself to use the prototype of the Nest system! Go to the system launch page.

Read more about the development of Nest (WP 1 of the MARE programme) in the programme plan.

Read more in the MARE programme annual reports about the development of the decision support system Nest.

Has scientific information been used before by decision-makers in the Baltic Sea region as a basis for environmental decisions? Read our report.