Socioeconomic and Environmental Benefits of Expanding Urban Green Areas: A Joint Application of i-Tree and LCA Approaches

Green infrastructures deliver countless functions for counteracting climate change, air pollution, floods, and heat islands, contributing at the same time to water and carbon recycling as well as to renewable energies and feedstock provisioning. Properly addressing such environmental problems would require huge investments that could be decreased thanks to the further implementation of urban forests. Local administrations are designing participative projects to improve territories and their living conditions. The i-Tree Canopy modelling tool and the life cycle assessment method are jointly applied to evaluate the potential benefits of increasing tree coverage within the boundaries of the Metropolitan City of Naples, Southern Italy. Results highlighted that tree coverage could increase by about 2.4 million trees, thus generating 51% more benefits in pollutants removal, carbon sequestration and stormwater management. The benefits are also explored and confirmed by means of the life cycle assessment method. The potential tree cover is expected to provide a total annual economic benefit of USD 55 million, purchasing power parity value adjusted, representing USD 18 per citizen and USD 99,117 per square kilometre of implemented urban forest. These results can support a potential replication elsewhere and provide a reference for the sustainable improvement of cities by expanding urban green areas.

Automated summary

Green infrastructures provide multiple benefits in mitigating climate change, air pollution, floods, and heat islands, while also contributing to water and carbon recycling, renewable energies, and feedstock provisioning. The implementation of urban forests can decrease the required investment for addressing environmental problems. In the Metropolitan City of Naples, i-Tree Canopy and life cycle assessment methods were used to evaluate the potential benefits of increasing tree coverage. The results showed that an increase in tree coverage can significantly enhance pollutants removal, carbon sequestration, and stormwater management. The potential economic benefit of the increased tree cover is estimated to be USD 55 million per year.