The framework is made up of three sub-models: assessment, forecast and management. Figure 3.2a shows the assessment sub-model, which is used to construct the ecosystem structure and to assess risks. First, species in an ecosystem are identified and then grouped by the self-organising mapping (SOM) analysis based on nine ecological characteristics (Chon et al., The ecosystem structure is constructed using the Ecopath model, which has been widely used to describe the trophic relationships in aquatic ecosystems on quantitative bases (Pauly et al.,