Ecological restoration of ecosystems

The "Jardim do Eucaliptal" (Eucalyptus Garden) in Benfica is undergoing extensive renovations to improve its facilities and usability. Over time, the intensive urbanization of this neighbourhood has not left many traces of the historic eucalyptus forest typical of this area, but this urban park actively protects and maintains these old and heavy-trunk eucalyptus trees, growing amidst the park's more recent vegetation (Ref. 3). In the last few years, several trees have fallen, causing considerable damages to buildings and vehicles in the nearby area (July 2023), and leading to residents demanding financial compensations for damages and for the Lisbon City Council (CML) to take action for mitigating future problems (Ref. 5).
The renovation project implementation, expected to last six months, includes refurbishing the children's playground, sports field, toilets, and amphitheatre, along with introducing a dog park and outdoor exercise equipment (Ref 1). The park, originally part of the Quinta das Palmeiras de Guerreiro Galla forest, remains a crucial green space in the area despite extensive urbanization (Ref 2). These renovations, with a budget of 180,000 euros, also address the maintenance of public street furniture, the pavement, and lighting infrastructure, ensuring that the park meets the growing needs of the local community (Ref 3). These activities aim to meet the growing needs of the local population and improve these urban green spaces so that the community can enjoy them to the fullest. (Ref. 4).

The Cinturón Verde de Independencia initiative is a pilot intervention that seeks to plant an urban forest in the lower middle-class district of Independencia (1) in the northern part of the urban territory (3). Here, 19% of the population lives in high-risk conditions, settled on steep slopes, and threatened by landslides (3).
It is part of a broader planning strategy that involves proposals engaging different levels of government (4). This project seeks to afforest the district's hillsides to improve the environment, reduce air pollution, improve the quality of life of its inhabitants, manage waste, regulate shade, control erosion, increase wild biodiversity, and provide spaces for environmental education (2). The Independence Green Belt is linked to a wide range of plans, projects, and decrees that have been developed by actors at different levels of government since 2016 (4). It works hand in hand with the EBA Lomas programme and seeks to create a green belt along the Lomas-city interface, which acts as a buffer zone for this sensitive ecosystem and creates a protective boundary against the expansion of irregular human settlements while providing a space for environmental awareness (2).
This program was developed by a consortium of multiple private, public, national, and international parties with strong community support (3). In two phases, an urban forest park of 4,800 of native trees irrigated with treated wastewater has been planted. During the first phase, PREDES planted 3,300 trees with USAID support in 2015, and another 1,500 were recently planted by PERIFERIA (consultants) (3).
The Independencia Green Belt occupies the hill areas of the district of the same name and relates to a possible metropolitan-scale buffer belt.
Its boundaries take advantage of the seven Sustainable Ecotourism Forest Parks (PFES) in the District Municipality of Independencia (MDI), as well as 115 hectares of the Amancaes Lomas (4). It aims to conserve 400 hectares (4).

Giulia's Farm is the first project launched by the Italian NGO Terre Colte in Sardinia, focused on transforming unused agricultural plots into a productive community garden. Initiated in 2014, the project covers approximately 3,000 square meters (out of 18,000 sqm owned by the NGO). The garden leases 50-square-meter plots to local residents, known as "ortisti," who cultivate the land using organic and natural farming methods. This approach not only revitalizes neglected land but also strengthens community bonds and promotes sustainable agriculture (Refs. 1 & 2).
The project operates on a cooperative model, ensuring that the land remains accessible and productive while fostering a connection between people and the environment. Participants share resources and knowledge, creating a network of mutual support that enhances both social and environmental resilience.
Beyond its agricultural impact, Giulia's Farm aims to preserve Sardinia's agricultural heritage and combat land speculation. By involving the community in farming, the initiative helps protect these plots from being sold for non-agricultural purposes, ensuring they remain dedicated to food production. The project also demonstrates the potential for reclaiming abandoned land, fostering local food production, and building a more sustainable and resilient food system.
Giulia's Farm has gained attention as a replicable model for other regions facing similar challenges of land abandonment and environmental degradation (Refs. 2, 3 & 4).

The Ciénaga de la Virgen is a coastal wetland (cienaga) located on the north side of the border of the city of Cartagena, separated from the sea by La Boquilla's sandy beach. It has a maximum width of 4.5 km, a length of approximately 7 km, a water body area of about 22.5 km², and depths of up to 1.6 m. It is connected to the city's canal system (ref 1). The recovery project of la Cienaga de la Virgen, led by EPA Cartagena, is proposed as a strategy to address the issues affecting the water body, local communities, the economic activities that depend on it, and the ecosystems that regulate the water cycle and provide multiple services, many of them essential, with an integrated and global management approach based on the basin as the unit for planning and resource management (ref 14). Some of the main problems of the wetland are related to illegal settlements on its shore, as well as illicit dumping of waste, pollution by wastewater from the illegal settlements and deforestation of mangroves (ref 4). Key activities include stopping illegal occupation by relocating established families, improving roads, promoting reforestation, encouraging social participation, managing wastewater, and enhancing tidal systems (ref. 1 and 15).
Alonside the EPA, other stakeholders involved include the regional authority "Regional Autonomous Corporation of the Canal del Dique" (Cardique), with jurisdiction in the rural area, and Cartagena Mayor's Office, and the local community, involved in all the stages of the plan thanks to the “mesas de governance” or "governance tables", discussion spaces where different actors participate in the decision-making (ref 2).

The Mziuri Park in the center of Tbilisi and adjacent to the city's zoo was heavily impacted by floods and landslides that occured in June 2015 in Georgia. As a result, many of its facilities were destroyed, necessating the redevelopment of the site (Ref. 1,2). In 2017, the Georgian government initiated the Urban Reconstruction and Development (GURAD) Project with funding from the European Investment Bank (EIB) under the 100 million € framework loan. The park's reconstuction is one of multiple projects under the natural disaster recovery component of the GUARD Fund (Ref. 1,2). As of 2020, the park has been fully redeveloped catering to the needs of diverse groups, but especially youth and children with a number of different sports, cultural and recreational areas (Ref. 3,4). Importantly, construction was carried out under consideration of spatial adaptation measures for people with disabilities and with a renewed drainage system to mitigate the effects of future floods (Ref. 1). The park is now again one of the most important recreational areas in Tbilisi (Ref. 3).

“The Orchards of the School” is a project led by Antibiotice S.A. through its foundation, "Știință și Suflet" (Science and Soul), which focuses on corporate social responsibility programs. Implemented between 2017 and 2019, employees volunteered to participate in planting orchards in the yards of several schools around the metropolitan area of Iași, including a special education school . The students assisted in planting the orchards and took responsibility for their management afterward.
The primary goal of the project was to instill respect for environmental protection, promote a healthy lifestyle, and cultivate civic spirit within the community among the younger generation. The local authorities prepared the yards for planting, while the Research and Development Station for Fruit Culture in Iași provided standardized methods for proper orchard cultivation.
By 2021 and 2022, the orchards were reported to be thriving and yielding their first fruits for the students (Ref. 1-9).

Lima is grappling with significant challenges driven by climate change, and one of the pressing issues is the shortage of green spaces. According to the PLAM 2035 report, Lima offers only 3.1 square meters of green area per inhabitant, well below the World Health Organization's recommendations (2). Moreover, food insecurity is on the rise, with Peru leading the region in this crisis (4). Compounding these issues is the lack of coordination among state actors tasked with addressing the country's food crisis (2).
In response to these challenges, the Energy Network of Peru (ISA REP) has been running the "Huertos en Línea" project since 2004 in the districts of Villa María del Triunfo and San Juan de Miraflores as part of its corporate social responsibility initiatives (2, 3, 6). This project aims to establish community gardens that promote environmental awareness, reduce pollution in these affected areas (1, 2), provide food for vulnerable populations, and create income-generating opportunities through the sale of surplus produce (1, 6). The gardens are strategically located in power grid easement strips, which are often plagued by encroachment, burning, and waste accumulation—issues exacerbated by poverty, extreme poverty, and weak social organization in these areas (5, 6).
Originally planned with an annual development and growth strategy up to 2011, the project has been extended year by year and has now been active for nearly two decades. Beneficiaries continue to receive technical and material support, and the number of community gardens has grown. In 2019, the initiative expanded to include two bio-gardens in the Trujillo districts of La Esperanza and El Porvenir (7, 9). The project has contributed to improving soil quality, recycling and transforming waste, enhancing landscape aesthetics, reducing burning and waste accumulation, and implementing drip irrigation systems.

In January 2024, the municipality of Cagliari inaugurated three new green areas in the city, adding five and a half hectares of green spaces for residents to enjoy. These areas are located between Keplero, Avicenna, and Parigi streets, not far from the city center (Refs. 1 & 2).
The primary goal of this initiative is to mitigate the effects of climate change, particularly rising temperatures. The green areas are designed to reduce the city's heat island effect and contribute to carbon sequestration. The planting of new trees will also help maintain ecosystems and improve environmental conditions in targeted areas . Special attention was given to soil quality, with most projects incorporating walkways equipped with drainage systems (Refs. 1, 2, & 4). Additionally, the new infrastructure aims to foster social engagement and attract more citizens, who will benefit from these improvements. (Refs. 1 & 2).
This initiative is also expected to boost the local economy by encouraging the development of small complementary services (Ref. 3). It is part of a larger municipal project co-funded by the EU.

Trade winds from the east over the Bay of Fort-de-France increase agitation at the "Étang Z’Abricots" marina, reducing user comfort and raising maintenance costs for port equipment and vessels. Climate change worsen these problems, increasing the risks of coastline erosion, extreme weather events, and rising sea levels, which may diminish the protective effect of "Pointe des Sables," leaving the marina more exposed to the winds (Ref 1; 2).

The Z’AB project aims to address these challenges by creating a protective barrier for the port by using mangroves. This involves installing lightweight, reversible devices to elevate the sea floor and accumulate sediments, encouraging the natural colonization of mangroves south of Pointe des Sables. Natural colonization refers to the growth of mangroves through processes like seed dispersal and sediment buildup. Once established, the mangrove will act as a natural buffer, protecting the marina from rough seas and adapting to rising sea levels. The project also includes educational efforts to raise awareness about the importance of mangroves for the region’s environmental issues and biodiversity (Ref 1).

Although the Z’AB project has been in planning since 2018, in 2021, a separate project to extend the marina, costing 7 million euros, was approved by the water park authorities (Ref 5). The extension will add 77 new vessel spaces (Ref 7), but it threatens portions of the mangrove and a strictly protected coral species, Oculina Diffusa, found in the area (Ref 6, p.17). While the marina extension project aims to offset the loss of coral and mangrove with various solutions, "Projet Z'AB" is not explicitly mentioned as a compensation mechanism (Ref 6, p.24). However, stakeholders involved in Projet Z'AB are also participating in the development of the marina extension (Ref 6). It remains unclear to what extent Projet Z'AB will be used to mitigate the environmental impact of the extension.

The Republic Services Garden is a one-acre garden created and located in Hance Park, a large urban park located in downtown Phoenix, Arizona. As part of the larger revitalization of the park, the garden was created to showcase native desert plants, recycled materials, and shaded seating, serving as a model for eco-friendly urban landscaping. Its key goals are to enhance the park's appeal, create a welcoming community space, and demonstrate the potential of sustainable design in cities. By blending nature with urban infrastructure, the garden helps mitigate the urban heat island effect, addresses water scarcity, and supports habitat restoration. The project is a collaboration between the City of Phoenix and the Phoenix Parks and Recreation Department, with financial backing from Republic Services, the second-largest waste disposal company in the U.S. (Refs. 1, 5, 7, 12, 15).