CREAF's research on urban trees takes centre stage at Smart City Expo 2026

The discussion on climate-resilient cities, part of the Smart City Expo 2026 held in Barcelona this week, incorporated a scientific perspective. CREAF contributed to the discourse on urban nature through the participation of its director, Joan Pino Vilalta, and researcher Mariona Ferrandiz Rovira. Joan Pino spoke during the session "Cooling, Greening and Financing Mediterranean Cities for Climate Adaptation"—organized by MedWaves—while Mariona Ferrandiz presented the ARSEC urban tree project and several of its initiatives at the South Korea pavilion.

The fragility and significance of urban green infrastructure served as the central theme for Joan Pino's remarks, in which he highlighted the constant coexistence between nature and people. The CREAF director also emphasized the fragmentation of urban green spaces, which are often confined to flowerbeds, median strips, tree pits, urban gardens, and the occasional green roof. This context "restricts root development and the connectivity between ecosystems", notes Joan Pino, adding that "as an artificial environment, it requires specific ecological design and management—one that can support native fauna, such as birds and pollinators, while also withstanding pests and droughts".

For this reason, Joan Pino noted, it is necessary to plan for the water and ecosystem services required to sustain urban greenery. Despite its limited scale, this nature helps mitigate the urban heat island effect and connects people with the environment. In light of rising temperatures, the director of CREAF highlighted the opportunity to look toward North Africa and the Near East to share experiences and best practices for designing resilient cities.

The round table in which Joan Pino participated is part of the Interreg Euro-MED "Green Living Areas" mission. Other participants included Carolina López, a researcher at MedCities; Sergi Cot, Councilor for Climate Action for the Girona City Council; Karim El Arnaouty, head of the AViTeM project; and Daniel Martínez Aller, coordinator of the Fundació Espigoladors.

The figures 252,908 trees planted in the city of Barcelona, ​​with 7,500 lost during the recent drought served as the starting point for researcher Mariona Ferrandiz Rovira as she explained the monitoring work conducted by CREAF in the city. Ferrandiz also highlighted Sant Cugat del Vallès and Granollers as municipalities that have experienced significant losses. In her presentation, "From Urban Ecology to AI-Enabled Regenerative Cities: Insights from Barcelona," she noted that the causes of urban tree mortality—and how to prevent it—remain poorly understood, largely because urban nature has been relatively understudied to date.
 

To address these questions and propose alternatives, two scientific initiatives have been launched to monitor the city's trees, involving CREAF, the Autonomous University of Barcelona (UAB), Barcelona Regional, and the municipal Parks and Gardens department. The first initiative, funded by Almo Nature and Fondazione Capellino, evaluates the actual adaptability of two species relatively new to the cityb —Zelkova serrata and Pistacia chinensis— which were planted in March 2026. The second, funded by the Barcelona City Council and the 'la Caixa' Foundation, analyzes the status of the city's three most abundant tree species, which were planted decades ago.

CREAF has installed dendrometers to measure changes in trunk diameter, along with sensors for soil and air temperature and humidity, to track how the trees grow and determine whether they require more water. The next step is to connect this data to the so-called 'Internet of Plants' enabling the management of urban trees in a manner similar to practices already used in agriculture. "This technological leap will bring about a profound shift in the profession of urban gardening", notes Mariona Ferrandiz.