The implementation of marine spatial plans as required by the Directive on Maritime Spatial Planning (MSP) of the European Union (EU) poses novel demands for the development of decision support tools (DST). One fundamental aspect is the need for tools to guide decisions about the allocation of human activities at sea in ways that are ecosystem-based and lead to sustainable use of resources. The MSP Directive was the main driver behind the development of spatial and non-spatial DSTs for the analysis of marine and coastal areas across European seas. In this research we develop an analytical framework designed by DST software developers and managers for the analysis of six DSTs supporting MSP in the Baltic Sea, the North Sea, and the Mediterranean Sea. The framework compares the main conceptual, technical and practical aspects, by which these DSTs contribute to advancing the MSP knowledge base and identified future needs for the development of the tools. Results show that all of the studied DSTs include elements to support ecosystem-based management at different geographical scales (from national to macro-regional), relying on cumulative effects assessment and functionalities to facilitate communication at the science-policy interface. Based on our synthesis we propose a set of recommendations for knowledge exchange in relation to further DST developments, mechanisms for sharing experience among the user-developer community, and actions to increase the effectiveness of the DSTs in MSP processes.
The space occupied by traditional and new human-based marine uses at sea is expanding, creating a need for developing methods to assess interactions between co-located uses in maritime spatial planning (MSP). However, no clear terminology for use-use interactions exists. Thus, an analytical framework for spatial decision support tools (DSTs) to assess use-use interactions is deduced from literature. Four spatial-temporal links are found to either alone or together constitute use-use interactions: location links, environmental links, technical links, and user attraction links. It is found to be important for DSTs to support co-location management in MSP by iteratively through the MSP process 1) spatially-temporally locate spatial-temporal links constituting use-use interactions, 2) list conflicts and synergies of the located use-use interactions, and 3) weight the conflicts and synergies. With this analytical framework, two types of DSTs are analysed for their ability to include co-location; matrix- and ranking-based DSTs to detect conflicts and synergies and space allocating DSTs to avoid/minimise conflicts and optimise synergies. Whereas the first group of tools categorise or rank use-use combinations, the latter group use information about which multi-use combinations are possible as pre-existing knowledge, and thus the two groups of DSTs can advantageously be used together. A discrepancy is found between the co-location framework and the DSTs. It is argued that future tools could work on removing this discrepancy by considering the spatial-temporal links of use-use interactions, strengthen the focus on synergies, as well as prioritize ranking of synergies and conflicts over binary approaches that only evaluate spatial compatibility.