Local government/municipality

The Establecimiento Público Ambiental (EPA) Cartagena has led multiple tree-planting initiatives in the Mamonal Sector as part of its ongoing efforts to promote environmental sustainability in Cartagena. The main goals of this initiative are to recover and enhance urban green spaces by planting trees, improve air quality and build a strong environmental culture within the community. In April 2024, EPA Cartagena led a tree-planting and public space recovery initiative in Nuevo Oriente, in collaboration with local authorities, community representatives, and the private sector, such as Veolia, as part of its ongoing efforts to strengthen environmental education and promote urban sustainability (ref 1). In a related tree-planting campaign, 210 new trees in Mamonal and Membrillal to help mitigate climate change, reduce air pollution, and protect local biodiversity. The effort received support from local industries such as Etex and AM SAS Mamonal. This campaign also aimed to enhance the natural environment in industrial areas and to encourage other companies and community members to join in environmental restoration efforts (ref 3).

In 2001, the local municipality of La Paz, in collaboration with the International Union of Architects (UIA), launched a design contest to create a central park within a protected natural area (3). The park's aim was to develop urban infrastructure while connecting nature with the city (3). The winning architectural design envisioned an infrastructure that would harmonize with the existing natural surroundings and minimize interference with the environment (4).
The park's implementation included pedestrian and bike pathways, numerous panoramic viewpoints, facilities for exercise and cultural events, buildings dedicated to science, historically significant monuments, playgrounds, and the rehabilitation and creation of multiple green spaces (1 & 4 to 6).
While most of the project was completed by 2009, the area's exposure to recurrent landslides, droughts, and illegal waste disposal, combined with ongoing degradation, has necessitated afforestation efforts and maintenance actions from the municipality to ensure the protection of the natural area and enhance its benefits (7 & 8). Recently, the park has been part of a national citizen monitoring program for species, which has improved the categorization of wildlife in the area (11 & 12). Additionally, 2,000 trees were planted in the park in 2023 as part of a reforestation campaign, and cleaning and watering maintenance work has been carried out to support their growth (7 & 13). This initiative is part of a larger project to revitalize the park (10 & 13).
Overall, the park aims to protect local wildlife and plant species while acting as a "green lung" for the city, regulating the climate, providing recreational spaces, and improving livability (14).

Ballymun is a suburban area on the north side of Dublin, Ireland. Originally developed in the 1960s, Ballymun was built to address Dublin’s post-war housing shortages, with iconic high-rise towers and flat complexes. However, over the years, the area faced social and economic challenges, leading to a reputation for issues such as poverty, unemployment, and lack of services.
In response, the Irish government launched the Ballymun Regeneration Project in the late 1990s. As part of the Ballymun Regeneration, Poppintree Park has been transformed into a 45-acre public space at the heart of Ireland’s celebrated urban renewal project in Ballymun Town Centre. This redevelopment followed an extensive public consultation process, incorporating input from local residents, sports clubs, community groups, and youth organizations.
Poppintree Park now offers a range of upgraded amenities, including a Tree Trail featuring 15 native tree species, enhanced biodiversity, extensive wetlands, sustainable drainage systems, and spaces for passive and active recreation. The park also features a 1.25-acre playground for children aged 0-12, an amphitheater with a permanent pond, and a fully accessible pathway network with abundant seating and viewing areas. Over 50,000 plants have been added to enhance the park’s natural beauty.
The park’s transformation, led by Ballymun Regeneration Ltd., involved significant engineering and landscaping efforts. Mitchell + Associates provided the detailed landscape design, construction drawings, and supervised the landscape works.
Completed in 2010, Phase 1 of Poppintree Park’s redevelopment represents an investment exceeding €6 million. The project includes substantial earthworks, drainage systems, gabion walls, three limestone-paved entrance plazas, structural retaining walls, a cantilevered pond walkway, diverse path surfaces, and high-quality playground construction. (1-7, 10)

This initiative was launched by the local government of La Paz, focusing on afforestation of the Mallasa landfill, which was closed in 2004 (1-4 & 6-10). While some plantations were established in the area when the landfill was closed, the overall plan aimed to manage the waste until the site was sufficiently clean for new projects—a process expected to take at least a decade (6). By 2021, signs of biodiversity, including flora and fauna, had begun to return to the former landfill. In response, the municipality of La Paz implemented a project to plant 6,000 native tree species, along with other shrub species, to further enhance biodiversity regeneration and establish a second urban forest in the city (3 & 4 & 7 & 8).

The afforestation efforts took place between 2021 and 2022, coordinated through "forestry brigades" made up of diverse volunteer groups. These groups included members from public institutions, private company representatives, NGOs (both environmental and non-environmental), universities, religious organizations, and local citizen groups (8-10). A total of 12 hectares were reforested out of the 33-hectare area (1 & 7). Following this, the area was closed to the public and is expected to become a biodiversity sanctuary within ten years, with ongoing monitoring by the municipal environmental agency (7). Among the trees planted, some were chosen to attract birds with their fruit, others to support the pollination of hummingbirds and bees, while others were intended to enrich the soil with nutrients—all species being native to the region (3 & 7).

Additional goals of the initiative include raising awareness about climate change, fostering a sense of environmental stewardship through community engagement, and advancing the municipality's decarbonization plans (3 & 9). Some of the seedlings and saplings were purchased by the municipality at a cost of 6,160 euros, with private companies also contributing financial support to the initiative (1 & 7).

The Loma del Marión recovery project in Cartagena, Colombia, is a community-driven initiative supported by EPA Cartagena that focuses on restoring and conserving the remaining 1.2 hectares of tropical dry forest. Initially covering 33 hectares, the area has suffered degradation due to illegal encroachments, deforestation, and waste burning. The project has included planting over 3,000 plants and fostering community involvement in environmental conservation (ref 1). The main goals are to restore the ecosystem by reforesting native species, preventing landslide risks, and developing an ecopark that will serve as an educational and recreational space. Planned facilities include a library for learning about local flora and fauna, hiking trails, and a community garden to enhance local food security (ref 1,4). A notable educational initiative in the project is the formation of "Vigías del Ambiente" (Environmental Watchers), a group of 40 youths from the Red Nacional Jóvenes de Ambiente, supported by EPA Cartagena and CDKN. This initiative educates young people on climate change, conservation, and waste management through workshops and activities (ref 2, 3). In addition, the EPA is leading detailed studies of the tropical dry forest to identify and protect endemic species (ref 5). The project has resulted in significant environmental and social benefits, such as planting thousands of trees, boosting community engagement in conservation, and establishing youth groups dedicated to sustainable development and climate action (ref 3, 5).

The Tagus Estuary Linear Riverside Park is a significant environmental and recreational project in Vila Franca de Xira. As part of a broader urban regeneration initiative, the park aimed to enhance the natural and cultural landscape by promoting ecological regeneration while providing public access to the Tagus River (Ref 1). Created in 2013, the park has won several international awards and since then, the park has undergone several extensions. In 2017, another 700-meter walkway was added towards Santa Iria, and the inhabitants of this urban area of Vila Franca de Xira widely use it (Ref. 6). The park covers over 14 hectares and includes pedestrian and cycling paths, environmental education facilities such as the Bird Observatory, and the Environmental and Landscape Interpretation Centre (Ref 2).
Recently announced in 2023, the park's newest expansion is set to extend the riverside trails further, creating a continuous route from Lisbon to Alhandra (Ref 5). With future phases planned, the project is expected to significantly increase public interaction with the riverfront and its biodiversity (Ref 5). In this new project phase, the Vila Franca de Xira Municipal Council begins the requalification and environmental and landscape conservation of another section of the riverfront of the Municipality of Vila Franca de Xira, between Alverca and Sobralinho, covering an extension of approximately 4.9 km and an area of ​​approximately 14.1 hectares (Ref. 7). The extension of the park will be developed similarly to its existing infrastructure. New paths for pedestrians and cyclists will be created using elevated wooden structures (walkways). In total, two new cycle-pedestrian trails will be created – Trilho das Comportas (3.32 kilometres long) and the Trilho dos Salgados (594 metres long) –, and the Trilho do Tejo will be extended by a further 990 metres (Ref. 5).

Kungsgärdet Byaodling is an urban farm set up by local farming association Kungsbacka Tillsammansodling, in Kungsbacka south of Gothenburg. Since 2023, the project has been funded by a 78 000 EUR grant via the non-profit organisation Lokalt ledd utveckling Halland (locally led development) using funds from the EU and the Swedish Board of Agriculture (Jordbruksverket) [Ref. 1, 2, 4]. The goal is to grow food in a sustainable and circular way, building soil health and promoting biodiversity. Using a total area of 4500 m2 on former unused grassland, the urban farm includes: 1100 m2 of effective growing area, 1000 m2 of flowering meadows, fruit and berry trees and bushes, and functional and social areas. The meadows and trees are intended to contribute to biodiversity, while social areas are meant to create a sense of community and benefit the well-being of the people active at the farm [Ref. 1, 3]. The farming association has been around for a few years, but the project funds will allow them to expand and develop the farm over three years, invest in new equipment and arrange free lectures for the public about sustainable farming practices [Ref. 1, 4]. The grant will also allow them to take in more members without anyone having to pay anything, promoting social inclusion.

In Egypt, knowledge about climate change remains limited, particularly among the younger generation. While all children globally face the challenges of a degrading natural environment and climate change, some are more vulnerable than others. This vulnerability is often influenced by the quality, availability, equity, and sustainability of essential services such as water, sanitation, healthcare, nutrition, and education. In response to these concerns, Egypt has taken steps to empower its youth to engage meaningfully in international efforts to combat climate change.
In 2022, with the support of UNICEF, the United Nations in Egypt, USAID, and the Embassy of Switzerland, Egypt's Ministry of Youth and Sports and Ministry of Environment launched the EGYouth4Climate Caravan. This initiative aims to raise awareness among children and young people about climate issues, encourage climate action, and provide a platform for youth to share their opinions and ideas. The caravan hosts a range of activities, including capacity-building sessions, youth dialogues, competitions, festivals, theatrical performances, bootcamps, and awareness campaigns.
One of the caravan’s stops was at the Nasr Youth Center in Alexandria, where a seed-planting workshop was held as part of the caravan’s reforestation activities. This workshop offered children a hands-on learning experience, teaching them about the importance of trees and providing an opportunity to plant seeds and trees across the center’s grounds. Through such initiatives, the EGYouth4Climate Caravan fosters climate literacy and environmental stewardship among Egypt’s youth, empowering them to take active roles in shaping a sustainable future. (1, 2)

In an architecturally important area of Berlin, situated between the Landwehr Canal, the Kulturforum (the Berliner Philharmonie and the Berlin State Library) and the new construction on Potsdamer Platz, a combination of green and grey infrastructure has been realised to minimise the burden on Berlin’s existing water infrastructure.
Green and non-green roofs harvest annual rain, which flows through the site’s buildings and is used for toilet flushing, irrigation, and fire systems. The roofs retain and then release water to the large on-site buffer pond, which has five underground storage tanks. Next to the roofs, a series of urban ponds and connecting canals have been implemented, with a combined area of approximately 1.2 hectares. They are filled with rainwater, creating an oasis for urban life. Vegetated biotopes are integrated into the overland landscape and serve to filter and circulate the water that runs along streets and walkways. The lake’s water quality is excellent, forming a natural habitat for animals and cooling the surroundings, while fresh water usage in the buildings has been reduced. (Ref. 1; Ref. 2; Ref. 3; Ref. 6)
The project was implemented in the 1990s as part of the development of Potsdamer Platz in the wake of the reunification of Germany. Several architects collaborated on the implementation that was completely privately funded. Beyond its ecological and technical features, the site is a blue natural site in the heavily built city centre of Berlin and allows people to linger and enjoy natural features. The drainage system won several sustainability prices and is considered a successful integration of nature and technology-based mechanisms to foster climate change adaptation. As the rainwater system stores rainwater in underground tanks and ponds, the urban sewage system is relieved during heavy rain, and water can evaporate. Therefore, the small water circle is closed, and the microclimate is cooled. (Ref. 2; Ref. 6)

The Green and Blue Axis (Eixo Verde e Azul, EVA) is an inter-municipal green corridor project connecting the municipalities of Sintra, Oeiras, and Amadora through a 15-kilometre green ecological axis along the Jamor River (Ref 2). It aims to renaturalize the river, improve water quality, and control flooding while promoting sustainable mobility through pedestrian and cycling routes (Ref 5). The project also enhances public access to green spaces and cultural heritage sites, such as the Queluz National Palace (Ref 6). EVA supports the Lisbon Metropolitan Area’s regional strategy for climate change adaptation, risk prevention, and low-carbon economy (Ref 4). Funded by the European Regional Development Fund and municipal budgets, the project has an overall investment of €11 million (Ref 1). EVA exemplifies inter-municipal cooperation, overcoming policy conflicts to achieve shared environmental, social, and economic goals, making it a model for integrated territorial development (Ref 4). The project’s long-term impact includes reduced carbon footprint and increased territorial cohesion.