A system dynamics model of urban forests to assess ES trade-offs and synergies in biophysical and monetary unit.

Oral Presentation Abstract Enhancing urban ecosystem services through the implementation of nature-based solutions (NBS) in cities can support a further integration of environmental objectives into urban planning. However, how to implement NBS to reduce the distance between urban planning and practical urban sustainable management and development remains an open question. In this study, we use a system dynamics framework to analyse the contribution of NBS, specifically urban forests, to address environmental urban challenges. An initial model of urban forest was developed to study i) regulation of temperature and humidity; ii) regulation of chemical conditions; and iii) provision of materials by respectively modelling changes in physiological equivalent temperature, carbon sequestration, and exploitable above ground biomass. The economic benefits (in terms of these services) and costs were then computed under several management and development scenarios representing alternative management types (i.e. trimming, harvesting) and built densities (i.e. low to high built density). As part of the modelling framework, several other ecosystem services, biophysical indicators, and their main socio-environmental factors and processes are identified and related to key urban challenges. The tested model shows the potential of urban forests’ for supplying ecosystem services and identifies different trade-offs on the regulation of chemical conditions and temperature depending on the intensities of wood harvesting and urban conditions (e.g. urban vs periurban), which together with the consideration of costs inform about economic benefits or loss. The use of a system dynamics approach applied to the modelling of NBS shows to be a valuable decision support solution to allow understanding how the concept of ecosystem services can be valuable for the planning and management of green spaces. Keywords: System Dynamics; MIMES; Nature-based Solutions; Ecosystem Services; Monetary Valuation