Establishing the links between marine ecosystem components, functions and services: An ecosystem service assessment tool

Although the concept of ecosystem services has been in use for many decades, its application for policy support is limited, particularly with respect to marine ecosystems. Gaps in the assessments of ecosystem services supply prevent its empirical application. We advance these assessments by providing an assessment tool, which links marine ecosystem components, functions and services, and graphically represents the assessment process and its results. The tool consists of two parts: (i) a matrix following the ecosystem services cascade structure for quantifying the contribution of ecosystem components in the provision of ecosystem services; (ii) and a linkage diagram for visualising the interactions between the elements. With the aid of the Common International Classification of Ecosystem Services (CICES), the tool was used to assess the relative contribution of a wide range of marine ecosystem components in the supply of ecosystem services in the Latvian marine waters. Results indicate that the tool can be used to assess the impacts of environmental degradation in terms of ecosystem service supply. These impacts could further be valued in socioeconomic terms, as change in the socioeconomic values derived from the use of ecosystem services. The tool provides an opportunity for conducting a holistic assessment of the ecosystem service supply and communicating the results to marine spatial planning practitioners, and increasing their understanding and use of the ecosystem service concept.