Private for-profit actor (e.g. firm, insurer)

Biotope City Wienerberg is located in the southern part of Vienna on a 5.4-hectare site that once housed a Coca-Cola factory. It lies at the edge of the Wienerberg recreational area, surrounded by business parks and tower blocks to the west and predominantly detached houses to the east (Ref. 1).
The project embodies the concept of an "urban biotope" (Ref. 2), grounded in the principle that nature's mechanisms of self-regeneration are essential for mitigating the challenges of urban living and climate change. By integrating urban and natural spaces, Biotope City fosters both human-nature connections and social interactions through activities like community gardening. The project’s centerpiece is its extensive green infrastructure, including trees and green roofs, which serve to cool the microclimate, purify the air, enhance water retention, and create carbon sinks while providing habitats for local wildlife. These green spaces aim to improve physical health through cooling effects on hot days and support mental well-being with their calming influence (Ref. 1; Ref. 2).
Biotope City encompasses:
Around 980 flats, including 400 subsidized flats and 200 SMART flats
A school, a kindergarten, and 2,000 square meters of children's and youth playgrounds
600 square meters of community gardens and 3,850 square meters of ground-floor gardens
250 trees, 8,900 square meters of meadows, and 13,600 square meters of green roofs
2,200 square meters of façade greening
The inner courtyards and roof areas are designed for gardening, while façades are greened, and balconies are equipped with integrated plant troughs. Even the spaces between buildings are climate-effective, featuring unsealed catchment and seepage areas to manage water sustainably (Ref. 1).
The project’s implementation took 18 years and involved collaboration among various stakeholders. The concept was initiated by the Biotope City Foundation and funded by eight different investors (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 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).

The Hellenic Park by Farka Lake stands as a symbol of the growing relationship between Albania and Greece (Ref. 1,2,3). The project was designed and implemented by the Municipality of Tirana in partnership with the Greek Embassy and supported by Greek companies operating in Albania. Its inaugurated was attended by the mayors of both capitals and the Greek Ambassador to Albania (Ref. 3,4). The opening ceremony marked three significant milestones: the 200th anniversary of the Greek Revolution, the 50th anniversary of the restoration of diplomatic relations between Greece and Albania, and the 40th anniversary of Greece's membership in the European Union (Ref. 4). The park reflects bilateral unity through emblematic vegetation, such as olive trees, which hold cultural significance in both countries. Beyond enhancing diplomatic ties, Hellenic Park fosters inclusive sports and cultural activities and provides a space for recreation (Ref. 1,3,4).

The greening of the Luceafarul theater esplanade is an initiative that is part of a corporate social responsibility strategy by the real estate company IULIUS (3, p. 86 & 89). The initiative aimed to expand and complement the green spaces and landscape design of the company's urban ensemble, Palas, located in the center of Iași (1 & 2). The space was previously occupied by a building owned by the company (5). Initially, the plan was to transform the building into a business center after donating it to the municipality (8). However, IULIUS and the Municipality of Iași agreed to demolish the structure and design a public space for the citizens instead (5 to 8). This decision was also influenced by the public’s desire to keep the area open, maintaining a clear view of the historical landscape, which was later incorporated into the municipality’s urban planning (8 & 9).
The design features a green field of 2,100 square meters, including 35 trees of various species (chestnuts, plane trees, and Ginkgo Biloba imported from nurseries in Italy) and 3,000 shrubs and bushes (1 & 2). The vegetation is maintained through an automated irrigation system (1 & 2).
The initiative aims to improve access to green spaces in Iași (3, p. 86) and to provide a space for recreation, relaxation, and leisure, with benches installed throughout the area (1 & 2). IULIUS intentionally places green space projects in central urban areas to ensure they are accessible to all residents (3, p. 86). Additionally, the municipality requested that the green space enhance the area's microclimate and improve the aesthetic appeal of the surrounding cultural landmarks (9, p. 6).

Planting Oxygen in the Community is an initiative initiated by the medical company Antibiotice S.A., one of the largest drug producing company in Romania, with headquarters in Iasi. The initiative involves an annual tree plantation campaign that has been carried out over the past four years. Originally implemented in cooperation with the municipality of Iași, the campaign is now independently managed by the medical company Antibiotice S.A. The selected planting area is located adjacent to the company headquarters in Iași and consists of undeveloped grassland.
Throughout the campaign, a total of 1,175 trees and 6,000 shrubs have been planted, including species such as oaks, lindens, and maples. The initiative has engaged 310 volunteers from the company to assist with the planting efforts.
The campaign aims to achieve several goals: rehabilitating green spaces, protecting the environment, reducing carbon emissions, mitigating the effects of climate change, and providing cleaner air for future generations. Additionally, it seeks to enhance the company’s environmental impact and foster social interaction among employees by reconnecting them with nature.
(1-8)

In 2024, Ozanam (a housing private company) and the French Development Agency (AFD) formalized a partnership to modernize an ecological wastewater treatment plant in Saint-Joseph, a neighborhood in Fort de France. The project focuses on replacing an outdated 30-year-old installation that no longer meets current standards with a plant-based water filtration system based on the ‘Rhizosph’air’ patent. This innovative treatment process utilizes "filter gardens," which combine mechanical systems, a gravity network, and a phytoremediation approach. The system employs filters made of gravel and the roots of local plants, specifically Strelitzia reginae and Cyperus alternifolius, to naturally and effectively filter wastewater without odor (Refs 2, 3, 4).
The nature-based system purifies wastewater over an area of 2,000 square meters, with a capacity equivalent to serving 900 residents. This approach offers several advantages, including reduced maintenance costs due to its simplicity, decreased energy consumption compared to traditional treatment methods, and improved water quality released back into the environment (Ref 2). Beyond its technical efficiency, the filter gardens enhance biodiversity (Ref 2) by improving the quality of water discharged into the environment and providing habitats for various species. The solution also integrates seamlessly into the landscape, showcasing vibrant flowers native to the area (Ref 1).
Additionally, the project implementers plan to construct a walking path, provide recreational equipment, and install benches to encourage residents to utilize the area as a public green space (Refs 2, 5).

The Praderas de Vida garden is an initiative to transform a former rubbish dump into a source of employment and empowerment for the residents of the Praderas de San Juan de Miraflores Human Settlement (1). This agroecological community garden was developed as part of ISA REP's Sustainable Easements programme (13), located in the easement area of Peru's energy network, and it has collaboration efforts with KUNAN, Misha Rastrera, and La Muyita, brings together twelve female heads of households who cultivate, harvest, and process a variety of medicinal plants that have aromatic, antiseptic, and relaxing properties (2, 3).
Beyond agricultural production, the garden has become a hub for emotional and economic support, fostering a connection with nature through plant care and interaction with the local ecosystem (3). It has also led to the establishment of a social enterprise, "Praderas de Vida," allowing women to participate in agroecological fairs to market the products derived from the medicinal plants grown in the garden (3).
The garden has evolved into a space for learning and community collaboration, promoting the importance of sustainability and biodiversity conservation (6).

The reforestation project at Bela Vista Park in Lisbon is a collaborative effort by the MEO Kalorama music festival, the Lisbon City Council, and Quercus (local NGO). The intervention began with a community planting event in February 2024 with the planting of 80 native trees, and the goal to plant a total of a total of 1,000 trees. The project aimed to improve the park's biodiversity, enhance carbon absorption, and support local wildlife. The tree species were chosen for their suitability to the local climate and their ability to integrate with existing vegetation. Local schoolchildren and residents participated in the planting, serving as a community engagement activity. This initiative is part of broader efforts to make Lisbon greener and to positively contribute to the local environment, given the disturbance caused by the MEO Kalorama festival (Ref 1, 2, 3).

Urban areas are particularly vulnerable to climate change due to the extensive use of concrete and asphalt, higher levels of pollution, increased population densities, and the concentration of infrastructure, all of which amplify the effects of extreme heat, drought, and severe weather. Urban tree cover play a vital role in helping cities mitigate the impacts of climate change by reducing greenhouse gases and alleviating the effects of extreme heat and other climate alterations that negatively impact human health. In 2023, dozens of volunteers from Bethune Elementary School planted 33 trees on the school grounds to provide future shade and help cool the environment. The project was funded by Arizona’s Public Service (APS) Community Tree Program, which aims to reduce the urban heat island effect by increasing tree canopy coverage in vulnerable communities.
The initiative was driven by Trees Matter, a local nonprofit organization focused on enhancing tree infrastructure in schools while educating students and staff on the importance of trees and tree care. Involving children in the tree planting process allows them to take what they’ve learned in textbooks and apply it in real-life situations, while also fostering a sense of community and belonging. This hands-on involvement not only educates but also creates lasting memories. The project’s goal is to combat the urban heat island effect by expanding tree canopy coverage, thus creating cooler, healthier shaded spaces for students in areas of Phoenix most affected by high temperatures.
With support from APS and Trees Matter, the volunteers worked together to plant trees that will provide much-needed shade on the school campus. APS’s Community Tree Program aims to provide shade and cooler spaces in neighborhoods that need it most, helping to reduce temperatures by 20 to 45 degrees. This effort is part of a broader initiative to improve the quality of life and mitigate the impacts of extreme heat in Phoenix (1-5).