Identifying and assessing the main categories of key performance indicators for nature-based solutions project monitoring

As the number of people living in urban areas is firmly increasing, more innovative solutions are needed to tackle the accompanying effects of climate change there, such as heatwaves, stormwater concerns or pollution. As these projects are continually developed and their effects are yet to be fully tapped, there is a lack of a coherent monitoring system. This study presents a systematic and comprehensive overview of three of the most recent studies of Sari et al. (2021), Connop (2020) and Elagiry et al. (2019), which list key-performance indicators (KPIs) for nature-based solutions. These indicators are grouped into six major categories, which are further divided into sub-categories. The results of the paper highlight the importance of a general and widely implementable monitoring tool system which is scalable and localizable for different urban settings, making it possible for individual nature-based projects as well as complex urban ecological systems to be well-monitored.