Design

This step includes the identification and selection of appropriate methods for the quantification, mapping and accounting (if applicable) of ecosystem condition. Methods should be chosen based on their ability to capture the structural, functional, and compositional aspects of ecosystem condition that are relevant to the assessment objective. Depending on data availability (cf. "Collect data") , methods can include field monitoring, modelling, remote sensing, or the use of existing datasets and proxies. Approaches should align with national or European-level frameworks where relevant (e.g. MAES condition indicators, EU Nature Directives, SEEA EA). Where relevant, this step may also include the selection of methods for setting reference levels and/ or conditions (RLs/RCs), which serve as normative baselines or benchmarks for assessing the quality or degradation of ecosystems. This involves defining the type of reference condition (natural, seminatural, or derived), and choosing among several RL quantification methods—such as using data from reference sites, statistical modelling, special value approaches (e.g. policy thresholds), or expert input. These considerations support the transformation of raw variables into interpretable condition indicators, in line with SEEA EA. In addition to individual condition indicators, approaches can be selected to compile composite or aggregated indicators that might provide integrated or summarised views of ecosystem condition. Such indicators can support communication, comparison, and aggregation across ecosystem types or regions. The step should involve designing relevant uncertainty assessments and could (if applicable) include the development of scenario assessments.