PROJECT DESCRIPTION
BACKGROUND
Air pollution is a major public health issue, causing an estimated 4.2 million premature deaths worldwide every year, including half a million in the EU. With over 80% of the EU population set to be living in cities by 2030, mass urbanisation presents one of the most urgent challenges of this century. Cities must cope with increasingly poor air quality, which impacts human health, quality of life, citizens well-being and the ecosystem services provided by urban forests. The economic cost is estimated at 330-940 billion (3-9% of the EU GDP).
South-eastern France and Italy are the highest risk areas for ozone (O3) in the EU, with the highest hourly maxima and increasing O3 levels in cities. In Florence and Aix-en-Provence, human exposure regularly exceeds EU limits for particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2) and O3, with air pollution 10-15% higher than national levels. The effects on human health locally are significant, including premature deaths and hospital admissions for cardiovascular and respiratory diseases.
OBJECTIVES
LIFE AIRFRESH aimed to estimate the air pollution (PM, NO2, CO2 and O3) removed by urban forests and shrubs in Florence (Italy) and Aix-en-Provence (France), using reforested test areas. The goal was to provide concrete integrated measures and recommendations for reforestation policies (e.g. the number and type of tree species to be planted) to reach legislative standards in both cities.
The project used a combination of in-situ observations, modelling and a geographic information system (GIS) to achieve the following objectives:
- Quantify and map the services provided by the present urban forests in filtering air pollution and storing atmospheric carbon in and around the two polluted cities;
- Rehabilitate urban ecosystem services to create cities for healthy people;
- Estimate and quantify environmental and health benefits provided by new reforested test areas in both cities;
- Evaluate the contribution of urban forests in achieving compliance with policy targets on air quality and climate change mitigation at the city scale;
- Evaluate the socio-economic impacts of cleaning urban air by urban reforestation;
- Propose a selection of suitable tree species, best practices and guidelines for planning and maintaining urban forests for cleaner air in cities;
- Support upscaling and replication of activities;
- Transfer know-how and best practices to policymakers and city managers in Europe; and
- Raise citizens and stakeholders’ awareness of the links between health and green cities.
The project contributed to the implementation, updating and development of local climate and air quality plans, as well as EU environmental policy, the urban agenda for the EU, the EU 2020 strategy and European smart city initiatives by supporting compliance with policy targets and stakeholder involvement. In particular, detailed information was provided to policymakers to assist in decisions related to land and improving green infrastructure, and maximising provision of ecosystem services.
RESULTS
The LIFE AIRFRESH project successfully achieved its primary objective of quantifying and enhancing air pollution (AP) removal through strategic urban forestry in Florence (Italy) and Aix-en-Provence (France). Two reforested urban test areas (totalling 2.2 ha) were planted with 800 trees, exceeding the initial target of 2 ha.
The project effectively measured the service of ecosystems provided by urban forests through advanced methodologies combining in-situ monitoring, satellite remote sensing, GIS mapping and modelling. The related maps were produced for both cities and show the enhanced air quality and carbon storage capabilities of reforestation.
These newly created urban forests demonstrated significant pollutant removal. Each area removed approximately 1.5 tons of ozone (O₃), 170 kg nitrogen dioxide (NO₂), 150 kg particulate matter (PM10) and stored approximately 21 tons of carbon dioxide (CO₂) per annum. They also reduced ambient temperatures by around 1.5°C compared to surrounding open areas. At its conclusion, the project surpassed its initial goals.
The dissemination activities have been effective and reached a variety of audiences, from the general public, students, the scientific community and policy makers. Results exceeded the expectations, with the engagement of over 470,000 citizens, including more than 300 students through guided tours and educational programmes. The project produced practical guidelines for local policymakers and city planners, including detailed lists of recommended tree species, best practices and maintenance approaches to enhance air quality. These guidelines have since been incorporated into urban planning in Aix-en-Provence and Florence, as well as regional plans such as the Regional Action Plan against ozone pollution (Provence-Alpes-Côte d’Azur).
Replication and knowledge transfer was successfully carried out in other European cities including Zagreb, Bucharest, Vilnius and Nice, through the organisation of workshops and stakeholder meetings and dissemination of materials that facilitated the wide adoption of AIRFRESH methodologies and tools across Europe.
From a policy perspective, the project significantly contributed to implementing and updating local Climate and Air Quality Plans and supported European policy frameworks such as the EU biodiversity strategy for 2030, and the Urban Agenda for the EU. The project's scientific outcomes and clear recommendations provided valuable support for policymakers, promoting sustainable urban development and informed decision-making in green infrastructure investment.
Socio-economic analysis has demonstrated significant health and economic benefits. Annually, the reforestation has helped avoid approximately 3 premature deaths, 12 hospital admissions and resulted in savings of €9.1 million in healthcare.
