NBS Design and Implementation in Urban Systems: Dimensions, Challenges and Issues to Construct a Comprehensive Evaluation Framework

The paper explores the recent challenge of implementing Nature-Based Solutions (NBS) in urban systems, as they represent an opportunity to address social, economic, and environmental issues. Furthermore, the design and implementation of NBS in the urban context are also supported by international and national policies, such as the European Green Deal, the Sustainable Development Goals (SDGs) and the Italian Recovery and Resilience Plan (PNRR). However, despite the growing attention on this topic, there are some critical aspects still unexplored. The European Commission discuss in-depth about these aspects, declaring them as the key points to set future research. Specifically, it has been pointed out that one of the main critical issues to be investigated concerns the development and test of Decision Support Systems (DSS), evaluation tools and models to comprehensively assess NBS interventions to support their design and implementation in urban systems. According to this scenario, this paper is inserted into this research topic. More in detail, the present dissertation is a position paper that underlines the main criticalities concerning the NBS evaluation and identifies a methodological framework and some evaluation techniques that could be used to structure an evaluation framework to overcome the highlighted gaps to answer real operative requirements.