Green space and habitat

Minimizing heat stress is a top priority for Phoenix, the hottest major city in the U.S. In 2023, extreme heat contributed to at least 359 deaths across Maricopa County. Phoenix is particularly vulnerable to climate change, with extensive concrete and asphalt, increased pollution, higher population densities, and concentrated infrastructure that exacerbate the urban heat island effect, drought, and extreme weather. Moreover, the heat disproportionately impacts lower-income and Hispanic neighborhoods, which tend to have less tree canopy and fewer resources to cope with rising temperatures.
To address these challenges and promote tree equity in underserved neighborhoods, the City of Phoenix, along with the Office of Heat Response and Mitigation, launched the Community Canopy Grant Program in 2023. The concept of tree equity refers to identifying areas with low tree coverage and high social need, then prioritizing investments in these areas. By improving tree equity, the program aims to assist neighborhood associations and community members in areas that need it most.
The Community Canopy Grant Program targets neighborhoods within Qualifying Census Tracts across Phoenix, and one of the first neighborhoods to benefit was Westwood. In early 2024, community members gathered to plant 200 box trees for residents who received grants, marking the largest City-sponsored neighborhood tree planting event of the season. These tree plantings aim to provide much-needed shade for homes while fostering community engagement, helping to mitigate heat stress and build stronger, more resilient neighborhoods. (1-5)

The 28th of October Street (28ης Οκτωβρίου) was one of the most neglected streets on the eastern side of Thessaloniki, completely devoid of trees despite its central importance. Additionally, the street suffered from severe flooding during heavy rainfall. In 2011, the Municipality of Thessaloniki, in collaboration with Konstantinos Zervas, the Deputy Mayor for the Environment, Quality of Life, and Free Space, proposed a redevelopment project aimed at transforming the street through the planting of trees and the installation of flower beds that would function as rain gardens (Refs 3, 5). This initiative was part of the "Integrated Green Cities" action, which falls under the European territorial cooperation program Greece-Bulgaria 2007-2013 (Refs 1, 2, 3, 6).

To achieve the dual goals of sustainable rainwater management and urban beautification, decorative trees were planted in specially constructed bioretention tree stands. These stands, along with the flower beds, were designed to collect rainwater, which would then be used to irrigate the trees along the road and the plants forming the rain gardens. Rainwater was gathered from the road surface, pavements, and the gutters of apartment buildings through these bioretention systems (Refs 1, 2). This sustainable water management solution significantly reduced rainwater runoff, improved water quality, and enhanced the area’s aesthetic appeal (Refs 2, 6, 7).

The Leopold-Rister park, named after a former district officer, is located in the Margareten district in Vienna and was renovated in 2023 based on the community's wishes for recreational opportunities. The park is surrounded by residential buildings and featured a playground for children, some greens and a football pitch. (Ref. 1) On the initiative of the city government, local residents and people using the park were surveyed on their preferences and needs for a potential redesign of the park. (Ref. 8) Within a year, the park was remodelled, featuring the wished for elements by locals, and was opened in 2024.
Spaces for recreation like playgrounds, benches, and gaming tables were increased or installed. To reduce the heat stress of the urban environment, trees were planted that provide shadow and water play for children to cool down were implemented. Already existing lawns and greens were restored, and new shrubs were added to provide habitats for different local insect and bird species. (Ref. 1; Ref. 6)
The project was initiated and financed by the City of Vienna and presents one of many greening activities that the city pursues to adapt to climate change. (Ref. 1; Ref. 2)

The project aims to restore green spaces in the neighbourhoods of San Francisco and 7 de Agosto. Led by Aguas de Cartagena, in partnership with other organizations, the initiative focused on environmental recovery, social integration, and reducing inequality through the revitalization of community spaces. Activities included planting native species, maintaining community infrastructure, and promoting environmental education, contributing to climate change mitigation and fostering a healthier, more sustainable environment​ (ref 4). As part of a collaborative effort between Aguas de Cartagena and SACSA, a synthetic grass sports field named El Wio was constructed with an investment of around 60 million pesos. The project aimed to foster community integration and provide safe spaces for sports and recreation, and it also included improving drainage systems, installing solar-powered lighting, and creating green spaces around the field (ref 5). Additionally, the Biblioparque, a community library and park in San Francisco, was rehabilitated to restore the library infrastructure, including terraces, reading rooms, and green spaces. The initiative provides a vital cultural and educational space for the community, especially for children, youth, and the elderly, fostering a culture of reading and community engagement. It also addresses previous safety concerns after a fire incident and aims to promote arts and cultural activities​( ref 3). In parallel, a long-term initiative, in collaboration with the local government, provided educational tools and resources to over 1,000 children and youth in San Francisco (ref 2).

The Garden Under the Walls, also known as the Garden of the Brothers Giuseppe and Vittorino Fiori, is a green space located in the historic Villanova district of Cagliari, along Viale Regina Elena. Inaugurated on 28 March 2014, the project transformed a long-neglected area beneath the Castello walls into a garden promenade. Closed to the public for many years due to ongoing construction, this green space has been reopened and returned to the city.
The garden spans 500 meters in length and covers an area of 6,500 square meters. The total renovation cost was 1.8 million euros.
The project focused on preserving the historical significance of the area while ensuring the safety of the Castello walls. The accessible pathway, designed to accommodate people with disabilities, features seven sculptures by renowned Sardinian artist Pinuccio Sciola, adding an artistic dimension to the space. This project successfully blends green spaces, accessibility, and culture (Refs. 1, 2, 3 & 4).

This mega-project is part of the Agenda for the Commemoration of the Bicentenary of the Independence of Peru (3). It is the new ecological lung of Ventanilla where families have free access to a meeting point where they can carry out sports, recreational, leisure and cultural activities (1, 2, 3). This park is the largest emblematic work carried out in Callao and one of the largest in extension at the national level, built in commemoration of the 200 years of independence (1, 2, 3). It was built on vacant land, where there was no possibility of meeting or recreation for the neighbours (1).
In addition to offering recreational spaces, it is a cultural work that seeks to teach the population about the history of independence, making the public space a commitment to a citizen-centred public policy with an intercultural approach (3). In addition, its financing was part of the second phase of the economic reactivation plan for public investment, encouraging local economic development and generating more than 1,300 direct and indirect jobs (3). This work is an investment of the Executive together with the Regional Government of Callao and the labour force of the municipality of Ventanilla (1, 2). Its facilities are freely accessible and will contribute to the social development and well-being of the citizens (3).
Inaugurated in 2022, it has cultural components, such as squares and amphitheatres, playgrounds, campsites and more than 30,000 m2 of green and blue areas (1).

Masthuggsparken is a planned park in the Masthuggskajen district, which is undergoing development and construction. The park will measure about 2000 m2, and serve as a green oasis and meeting place for locals. It will have ameneties such as benches and areas for play, and a noise barrier against a large nearby road. The park will connect to the adjacent square and street, making it accessible to visit. The street will be renovated to have more trees and plants, increasing green connectivity in the district. The park will be surrounded by trees and other plants, which are planted to promote biodiversity and be adapted to a changing climate [Ref. 1-5, 7]. The park is at a low point, where up to 800 m3 of stormwater will flow during heavy rainfall, reducing flood risk in the surroundings [Ref. 1, 2, 6]. The Masthuggskajen district has a sustainability program, establishing goals for green environments which the park will contribute to. Green areas should be accessible to the entire district and provide ecosystem services such as rainwater management, climate adaptation, biodiversity and recreation. The program was created by the City of Gothenburg in collaboration with construction companies active in the area and was supported by Citylab Action, a national competence program in sustainable urban development [Ref. 7]. The City of Gothenburg is the primary responsible for the park, which will be constructed between 2025 and 2026 [Ref. 1, 2, 4].

The Vale da Ameixoeira Urban Park is a key part of Lisbon's Peripheral Green Corridor, covering 20 hectares and aiming to enhance the city's ecological and social resilience. It includes pedestrian and cycling paths, rest areas, picnic spots, skate parks, and playgrounds, enabling recreational activities while providing scenic views (Ref 1). The park has undergone several requalification initiatives, including the tree planting project in 2018, which saw the community and municipal bodies plant over 130 native trees and shrubs, promoting biodiversity and environmental sustainability (Ref 3). Additionally, the park supports community-based vegetable gardens, integrating horticultural practices to promote local engagement and foster social inclusion (Ref 3). More recently, as part of the Life Lungs project, another 600 drought-resistant trees were planted to mitigate climate change impacts, such as urban heating and water scarcity (Ref 5). The Lisbon Participatory Budget funds the project and reflects the community’s demand for sustainable urban development (Ref 2).

The intervention in the Sant'Elia neighborhood, which opened in 2018, created a new green area of approximately 2,600 square meters designed to enhance the urban environment and improve the quality of life for residents. This space includes an olive grove and an orchard, featuring pathways and landscaping that integrate local plant species.
Along the side facing Via Utzeri, olive trees and a small grassy area have been planted, complemented by stabilized gravel paths for walking. The orchard contains 28 fruit trees, including citrus, pomegranate, quince, and fig trees, along with Mediterranean shrubs, allowing residents to freely enjoy the fruits for their own consumption.
The entire area is equipped with an automated drip irrigation system, while the grassy sections utilize sub-irrigation. Additionally, a central roundabout in Piazza Giovanni da Verrazzano has been adorned with a lawn, palms, and vibrant rose beds.
Commemorative plaques honor tenor Piero Schiavazzi and local resident Samuele Utzeri, who tragically passed away in Kosovo. The area also features signs encouraging respectful harvesting of fruits and permits dogs, provided they are kept on a leash (Refs. 1, 2, 3, 4 & 5).

The Tirana Vertical Forest is part of the city's 2030 Master Plan and aims to enhance urban biodiversity and create green spaces through innovative urban design (Ref. 1,2). The project was developed by Stefano Boeri Architetti, the same studio that has designed similar, well-known structures in cities like Milan, Utrecht and Nanjing (Ref. 6). The completion of the 21-floor building is expected in late 2024 and will feature 105 apartments and a commercial ground floor as well as 145 trees and over 3,200 shrubs and bushes which are integrated into the balconies and façade of the project (Ref. 1,2,3). Various Mediterranean plants have been incorporated, including colourful, scented and aromatic types, which harmonize with the local ecosystem. To maximise the space available for green features, a dynamic structure with alternating balconies and full-height windows has been built (Ref. 1,2). Ultimately, the project anticipates improving air quality, reducing noise, and providing insulation. The greenery is expected to capture fine particulate matter and up to 8 tones of Co2 per year while also creating a healthier microclimate for those inside the building (Ref. 1,6).