Landfill reclamation

Public spaces in Colombo are disappearing due to rising land prices, causing infrastructure issues that harm citizens' health, especially in low-income areas (3). One proposed solution to address the problems caused by rapid urbanization is the creation of community gardens, which can at least improve low-income residents' diets and immune systems and address malnutrition (3).
Considering the limited urban space for both citizens and other living beings, the organization Eco-friendly Volunteers decided to create a community garden. The Metta Garden in Colombo (1, 2) aims to bring back urban biodiversity through organic home gardening, generating healthy food for people and creating living space for many other animals and plants (2). Following the Buddhist concept of Metta (loving-kindness to all beings), it promotes walking meditation paths and facilities to experience nature using all five sensory organs (1), in addition to being a place for experiencing loving-kindness for both human and non-human living beings, seen and unseen (4, 5).
It has become a training institute for many stakeholders seeking to grow organic food and earn a better income through the high demand for organic products (2). At the same time, it serves as a biodiversity spot, attracting butterflies, bees, and other forms of wildlife to an urban environment (2).
The area is located in the middle of a semi-urbanized area, on the outskirts of Boralesgamuwa (2, 3). Maintained by a group of volunteers, it features a greenhouse and a plot of land of around 5,000 sq feet, populated with vegetable patches, a butterfly garden, flowers and rare medicinal plants (3, 4). The garden was divided into four sections representing the Buddhist elements: water, heat, air, and solid. Each section features specific plants and designs, like a pond for water, a compost pit for heat, tall plants for air, and a rock garden for solid. The layout follows a mandala design based on permaculture principles (4).

In 2022 an afforestation initiative was implemented near a landfill located in the Tutora commune (1 - 6). Organized by the City Hall of Tutora, the event brought together representatives from the regional government of Iasi County, the "Asociația de Dezvoltare Intercomunitară pentru Salubritate" (ADIS), and volunteers from SC Girexim SA, SC Salubris Iasi, and Edil Industri Iasi. Together, they planted 2,000 acacia saplings, donated by the Forestry Directorate of Iasi (6). The afforestation action took place under the umbrella of the regional environmental campaign "Iasi Mai Verde" (Iasi More Green), led by the County Council of Iasi. This campaign promotes a range of eco-friendly activities, including educational programs in schools, waste cleanup events, and afforestation initiatives in partnership with ADIS, while actively encouraging the support and participation of local municipalities from across the region (1, 3, & 7).
"Iasi Mai Verde" aligns with national environmental strategies such as the Ministry of the Environment's "Curățăm România" (Let's Clean Romania) and the annual Planting Forest Month (3 & 6).
On the same day, as part of the Iasi Mai Verde initiative, students from a local school in Tutora were given a practical education workshop on how waste management operates at the regional level. The students were also invited to witness the afforestation action and participate, fostering a deeper understanding of environmental stewardship (1- 5).
The newly planted trees are acting as a natural barrier, and help improve air quality by filtering dust, pollution, and waste particles originating from the nearby Tutora landfill. In turn, this contributes to better living conditions for the residents in close proximity to the landfill, enhancing both their health and overall quality of life (5).

The Kikås dump is a landfill in Mölndal, south of Gothenburg, where an area has been permanently covered with a sealing layer and inert material. This project aimed to utilise the area to increase biodiversity by establishing flowering meadows and an insect hotel, creating a habitat for wild bees, butterflies and birds [Ref. 1-3]. The City of Mölndal initated the project and sowed meadow flowers, established sand beds for burrowing insects, an uneven, rocky terrain and a large insect hotel [Ref. 1, 3]. The area is also meant to be a destination for recreation and learning about biodiversity. The Insect Hotel is marketed as the largest in Sweden, and it includes information signs and an outdoor classroom. The project is meant to raise awareness about biodiversity and ecosystem services such as pollination [Ref. 1, 4-6]. The area borders natural areas such as forests and wetlands and is meant to have positive ecological effects in the border zones. The project will contribute to the environmental goals of the city, in particular, "a rich plant and animal life" [Ref. 3]

The Fairy Garden, also known as the WOW Recreational Park, is a distinctive green space located near Diósgyőr Castle in Miskolc, Hungary. Since its opening in April 2020, the park has quickly gained popularity, earning third place in the 2020 Tourism Attraction of the Year award in the professional category. Once a neglected and polluted site with historical significance, the area was transformed by a local entrepreneur. After removing over sixty containers of waste, including hazardous materials, a park was created that harmonizes with the natural environment, preserving existing willow trees and integrating water features fed by local streams. When creating the park, the creators respected the plants of the area to the maximum, not a single tree was cut down, and the fruit trees were also kept.
The park boasts various decorative elements, including a carousel, a garden cinema, and other amenities. However, in September 2021, it was closed indefinitely for renovations. Gábor Vaszil, the lessee who had rented the land from the Miskolc municipality, intended to purchase the property for further development. Despite initial support from the local government, the transaction was halted due to concerns raised by the regional Water Management and Protection Authority regarding the protection of Miskolc's drinking water resources. Their ongoing investigation has delayed any further decisions about the sale or the future of the park. In the meantime, the garden remains open to the public for leisurely walks, similar to other municipal parks in Miskolc.
(Ref.1-4)

The initiative consists of an afforestation campaign promoted by the local government of La Paz, with the objective of planting 10,000 trees and shrubs (1 & 2). Carried out between 2023 and 2024, the campaign included plantations across all the macrodistricts of La Paz (1). To ensure the campaign's success, the municipality encouraged the participation of volunteers from various institutions, such as public services, environmental groups, schools and universities, neighborhood associations, church groups, and even Army and Navy units (1 & 2). The trees play specific roles in mitigating climate change, improving air quality, reducing odors from nearby landfills, and decreasing the risk of landslides and soil erosion (3 & 4). Furthermore, the campaign aims to foster environmental awareness among citizens and replace trees lost due to illegal deforestation (1).

The species selected for planting were provided by EMAVERDE, the public company responsible for managing green spaces in the city. The selection included primarily native species, along with a few introduced ones, all chosen for their resilience to La Paz's varying climate conditions (1, 2 & 4). Given the challenging climate and difficult soil conditions, the municipality informed volunteers about the importance of maintaining the saplings, particularly during drought periods, to ensure their proper growth (1 & 2). The campaign also supported the municipality’s urban development plan (Plan Territorial de Desarrollo Integral "Para Vivir Bien") and the "Plan Integral de Recuperación de la Tormenta a la Esperanza," the latter developed in response to extreme rain events and floods that occurred during the campaign months (5).

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 Oxygen Alley project, developed by the NGO Arboretum Detroit, is a green space located in the Poletown East neighborhood of Detroit. Spanning four formerly abandoned lots, the project, completed in 2023, serves as a significant environmental and community initiative aimed at improving local resilience and promoting environmental justice. Named in recognition of the closure of the Detroit waste incinerator—a major source of pollution for over 30 years—the project replaces a long-abused landscape with a thriving greenway that enhances both the ecological health and social well-being of the area.
Key features of Oxygen Alley include the planting of air-filtering trees and the creation of a shaded greenway lined with wildflowers, benches, and walking paths. This new green space not only provides a recreational area for residents but also functions as a natural air conditioner, stormwater sponge, and wildlife habitat. It addresses the neighborhood’s lack of tree cover, offering shade and cleaner air while helping mitigate the effects of climate change.
The project also underscores the neighborhood's longstanding struggle for environmental justice. The removal of 400 feet of asphalt and the remediation of a polluted landscape highlight the community’s efforts to reclaim and revitalize their environment. Oxygen Alley serves as both a functional green space and a monument to the residents’ victories over the waste industry, symbolizing their continued fight for clean air and livable spaces.
Supported by grants from the City of Detroit, Michigan Department of Natural Resources, and DTE Energy Foundation, among others, the project was brought to life through over 300 hours of volunteer labor. The creation of this greenway not only improves the neighborhood’s walkability but also offers a vision for a more sustainable and equitable future, serving as a model for urban revitalization projects across Detroit and beyond.
(Ref.1,2,3)

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).

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.

Trénelle-Citron, located north of downtown Fort-de-France and separated by the city bypass, La Rocade, was originally established in the 1940s by Black Martinicans migrating from rural areas. Today, the neighborhood faces significant economic and social challenges. In 2016, young residents from the neighborhood alongside a local NGO launched a grassroots initiative to improve their community. They transformed a former municipal quarry, which had deteriorated into an informal dump, into a thriving shared urban garden, benefiting the local population. This project, based on traditional ecological gardening techniques and the cultivation of native crops, aimed to revitalize Trénelle-Citron—a densely populated area grappling with social exclusion, a shortage of green spaces, and limited economic opportunities for its youth (Ref 2).

The garden, developed on municipal land with guidance from the Ypiranga Martinique NGO, support from the local school, and collaboration from various stakeholders, now plays a vital role in the area. It raises awareness about agroecology, offers socioeconomic opportunities, promotes healthier lifestyles, and fosters social connections among residents. Spanning approximately 1,000 m², the site includes an office, a covered area, tool storage containers, market garden plots, a composting area, and a chicken coop managed by a local resident (Ref 7). In Martinique, such shared urban gardens are increasingly seen as important tools for sustainable development (Ref 5).