Trees, forests and public health – evidence-based Nature-Based Solutions
2024–2025 · Regione Lombardia – Directorate General for Welfare · University of Milan · The project Effects of trees and forests on public health: an evidence-based synthesis supports Regione Lombardia in the structured use of scientific evidence to plan, implement and assess Nature-Based Solutions (NBS), with particular attention to trees, urban forests and other green spaces. · The research conducted a systematic review of 143 scientific studies on the effects of NBS on human health in urban and peri-urban settings. Outcomes included mental health and psychological well-being, cardiovascular and respiratory health, physical activity, mortality and morbidity, pregnancy outcomes and other indicators of health and quality of life. · Results indicate that benefits depend not only on the amount of green space but also on its quality, structure, accessibility, spatial distribution and use. Main mechanisms include mitigation of urban heat, improvements in air and acoustic quality, promotion of physical activity, stress reduction and stronger social cohesion. The review also considers null or adverse findings, including possible effects associated with allergens, vegetation characteristics and intervention location. · Final report – Effects of trees and forests on public health: an evidence-based synthesis (31 January 2025) · Annex 1 – Synthesis of reviewed studies · Annex 2 – Monitoring protocol · Annex 3 – Case-study sheets · Annex 4 – Policy brief
Alongside the evidence synthesis, the project developed an operational monitoring protocol. Existing NBS can be assessed through single-phase baseline monitoring, while new NBS are evaluated through a pre/post-intervention design with measurements at 12 and 36 months and longer-term follow-up. The protocol combines environmental and spatial data with questionnaires addressing exposure, use, perceived quality, physical and mental health and well-being. The project also analysed international case studies selected for their transferability to Lombardy and produced a policy brief for public decision-makers.
The overall aim is to connect green-space design, climate adaptation and public-health prevention and to provide tools for evaluating not simply the presence of NBS but their actual capacity to deliver measurable health benefits. UniMi Authors: Alberica Orsa Maria Mion and Giorgio Vacchiano
Related research lines: Urban forests and nature-based solutions · Monitoring, remote sensing and forest modelling