A. All stakeholders benefit fairly from the project

The Surco district of Lima has implemented a vertical bio-garden occupying a 685 square meter area within El Aire Park. The garden comprises a 600-meter linear structure supporting 11,000 planters fabricated from recycled plastic bottles. This system yields a substantial crop production of between 400 and 1,500 varieties on a 20-day cycle (1).
Initiated by the Municipality of Santiago de Surco, the bio-garden is designed to contribute to the district's economic, nutritional, and environmental sustainability (1, 2, 3, 5). By cultivating high-protein, nutrient-rich crops, the municipality provides essential sustenance to 24 local community kitchens (1), a local market (3), parishes, and social aid organizations (1).
To optimize crop yield, the municipality has implemented specialized techniques, including seedling cultivation, harvesting, and organic fertilization, to prevent pest and disease infestations (1). Since its implementation in 2020 with an initial 7,000 planters, the project has expanded by 300% to accommodate 11,000 (1). Cultivated plant varieties include medicinal herbs, leafy greens, root vegetables, and infusion ingredients (2, 5).
Additionally, the initiative serves as an educational platform, demonstrating and spreading sustainable home gardening practices utilising recycled materials such as plastic bottles (3, 5).

A community garden opened in 2023 on the Technological University (TU) Dublin Blanchardstown campus. This environmental education and social inclusion project is a collaborative effort involving Fingal County Council, Global Action Plan Ireland, TU Dublin, and the local community. It provides a space for local groups and schools to grow fresh produce, reconnect with nature, and foster a stronger sense of community.
Rooted in a successful template developed by Global Action Plan in Ballymun, this initiative promotes social and cultural inclusion alongside environmental education. The Green Living & Sustainability Community Garden (GLAS) aims to create an inclusive environment that welcomes individuals of all ages, abilities, and backgrounds. More than a site for cultivating plants, flowers, and vegetables, the garden serves as a hub for fostering social connections, enhancing well-being, and offering valuable educational opportunities.
The garden provides individuals with the chance to engage in social horticulture, exploring the connections between food, health, biodiversity, and global issues such as climate change. It operates on organic and regenerative principles, with all tasks and harvests shared by volunteers. Additionally, the garden will support youth gardening projects and public workshops on topics such as growing food, composting, water harvesting, and waste management. Beyond its environmental benefits, the garden helps people connect with one another, positively impacting social, physical, and mental well-being.

The city-wide project Urban Trees for Berlin was launched in 2012 with an ambitious goal: to plant 10,000 roadside trees within five years. This campaign, a key part of the Berlin Senate's Urban Green Space Strategy, is a collaboration between the Senate Department responsible for the environment and Berlin’s district authorities. Initially set to end in 2017, the campaign was extended through 2026.
The project was created to address the loss of numerous roadside trees that were removed due to age, pests, climate stress, and other factors. Limited funds had been available to replace these trees, resulting in negative impacts on Berlin's urban climate, including higher temperatures and worsened air quality, which affect both residents and visitors. The campaign aims to reverse these impacts by securing funding for new trees, restoring greenery to the city streets, and promoting a lasting positive image of Berlin’s urban trees.
The campaign operates on a co-funding model, where individuals, organizations, and companies donate €500 per tree (individually or collectively), with the Senate covering the remaining costs from the state budget (approximately €2,000 per tree). The planting schedule and locations are organized twice annually, with information shared online to keep the public informed.
In 2022, a new assessment of the project’s progress was conducted, commissioned by the Senate to the Arbo-tec office. Around 1,000 of the 3,500 trees planted as part of the campaign by autumn 2022 were evaluated. The selected locations included plantings from all previous construction phases, spanning 12 Berlin districts, with each district having 80 trees assessed from various phases and construction lots. This comprehensive evaluation is intended to ensure the long-term success and sustainability of the Urban Trees for Berlin initiative. (3, 4)

The project aims to modernize Ciurchi Park, also known as "Tătărași Park," due to the degraded state of its current infrastructure (1 - 8). Initiated by the Municipality of Iași, the initiative seeks furthermore to increase the amount of green space per inhabitant in the city and reduce overcrowding in other parks, thereby diversifying options for citizens (1 - 9). Planning for the project began in 2022, and the bidding process for its execution was released in April 2024, which is still awaiting a decision (1, 2. 7).
The implementation is expected to involve interventions in existing green spaces, including the planting of 120 trees, 1,000 bushes, and approximately 2,000 species of flowers and ornamental plants. The project will also feature a monitoring program for tree species, management of existing vegetation to protect healthy trees, and removal of invasive or degraded plants (1, 2, 4, 8). Additionally, it will include benches, facilities for physical exercise, an underground waste collector, and a rainwater drainage system, among other infrastructure improvements (1 to 8).
The project is expected to be financed by the local budget and EU funds, with a total estimated cost exceeding 5,000,000 euros, including taxes (2, 4). It is included in the Integrated Urban Development Strategy 2015-2030 for the city (8, p. 12).
The goals of the project are to modernize the park, improve accessibility for citizens in the surrounding area, minimize management costs for the municipality, ensure a sustainable habitat for flora and fauna with minimal invasive interventions, and harmonize architectural proposals with the landscape (6, 8, p. 32). Other objectives include protecting biodiversity, enhancing the park’s aesthetics and the overall city environment, and reducing CO2 emissions, which will ultimately improve the quality of life for surrounding residents (8, p. 141).

Bound by miles of steel, concrete, or brick walls, Berlin’s rivers and artificial canals often look alike. Plastic bottles, along with ducks, swans, and perhaps the occasional coot seeking scraps from humans, are some of the few visible signs of life. Underwater, the scene is similarly sparse and monotonous, with only a handful of resilient species able to endure the harsh conditions.
In response to this lack of biodiversity, researchers from the Leibniz Institute for Freshwater Ecology and Inland Fisheries in Berlin collaborated with the engineering firm Wite to create the Vertical Wetland project. This initiative introduced plant boxes that attach to sheet piling along canal walls, extending into the water to form miniature habitats. These boxes serve as refuges for insects, birds, fish, and other small animals, offering hiding spots and sheltered spaces for egg-laying among the roots and boxes protruding into the water. Known as "ecological stepping stones," vertical wetlands enable animals to rest and safely traverse urban waterways, fostering biodiversity along urban riverbanks.
Vertical wetlands present a quick and cost-effective way to ecologically upgrade sections of urban waterways. Although they can’t fully replace natural riverside habitats, these mini-habitats offer substantial ecological benefits. Native river floodplain plants, including willows, reeds, rushes, and shallow-water species like irises and marsh marigolds, provide the foundation of these structures. All materials used are environmentally friendly and biodegradable.
By covering the grey, industrial surfaces of riversides, the vegetation cools the local environment, both on land and in the water, and helps improve water quality. Plant shading cools water, reducing eutrophication risks and creating a healthier habitat for aquatic life.
The Vertical Wetland project’s pilot installation was successfully implemented and tested in 2023 in the Berlin-Spandau Ship Canal. (1, 3, 6)

The Detroit RiverWalk is an urban development project along the Detroit River, designed to reconnect residents with their waterfront and revitalize a historically industrial area. Once characterized by abandoned buildings and industrial debris, the riverfront between the MacArthur and Ambassador Bridges had long been inaccessible to the public. To address this, the Detroit Riverfront Conservancy was established in 2003 to lead the redevelopment of this space.
The RiverWalk currently stretches along a 3.5-mile section, with plans to expand to 5.5 miles, integrating ecological restoration, public access, and recreational opportunities. The esplanade features native landscaping, artistic elements, and amenities, including four pavilions, a custom carousel, and areas for fishing, walking, biking, and inline skating.
Environmental remediation has been a crucial part of the project. In collaboration with the U.S. Environmental Protection Agency’s Great Lakes National Program Office, the Detroit Riverfront Conservancy successfully cleaned up 13,000 cubic yards of contaminated sediment, significantly reducing pollution and contributing to the removal of the Detroit River from the list of the most polluted sites in the Great Lakes. Furthermore, the project also includes greenways, park creation and revitalization.
The RiverWalk is not just a public space; it symbolizes Detroit’s transformation from a Rust Belt city to a sustainable urban environment. It exemplifies the power of public-private partnerships in revitalizing urban areas. The RiverWalk continues to expand, with plans to connect various parks and extend to the Ambassador Bridge, further enhancing the city’s waterfront. Its success was recognized in 2021 when it was named the Best Riverwalk in America by USA Today, cementing its status as a model for urban renewal and community engagement. (Ref. 1, 2, 3, 4)

Salines Beach, a popular destination for over a million visitors annually (Ref 9), is facing severe erosion due to rising sea levels and poor coastal management. Since 1995, the beach has lost more than 20 meters in width. This loss has been worsened by vehicle traffic and the introduction of coconut trees in the 1950s, which reduced the native root systems that once helped to stabilize the coast (Ref 5). Now, the encroaching sea threatens to swallow the road that runs along the beach.
In response, the Salines Conservation Committee—comprised of concerned community members and environmental groups—has been advocating for urgent action to halt the erosion. They have called for a renaturalization of the area through the replanting of endemic species and restrictions on car traffic, both aimed at restoring the beach’s natural resilience.
When part of the road collapsed in July 2022, the committee took immediate action, organizing community-based interventions. These efforts included blocking traffic, raising public awareness, and planting over 60 endemic plants in the damaged area. The aim was to reestablish a root network capable of anchoring the coastline and capturing shifting sands (Ref 1; 2). The intervention was described as "a response to the urgent need to rebuild the root network, an ecological engineering solution recognized as the most effective method for retaining beach sand and slowing coastal erosion" (Ref 2; 1). The intervention on this section of the coast was first completed, then discarded by the municipality of Sainte-Anne (Ref 2). Regional and National agencies are currently undertaking the restoration works but it is unclear the stage of completion (See Ref 3).

In 2021, the real estate company Inamstro, in collaboration with the Municipality of Iași, the civil organization "Glasul Vieții" (Voice of Life), and local citizens, initiated a tree-planting initiative that involved planting 250 trees near a residential area and a parking lot in the Frumoasa neighborhood of Iași. This neighborhood is smaller compared to other areas of the city and was developed during the communist systematization of the 1970s and 1980s. It consists of groups of four-story blocks arranged around common spaces, situated near the Frumoasa Monastery complex.
The main goals of the 2021 planting action were to enhance green space, lower air temperatures, reduce urban air pollutants—such as fine particulate matter—absorb CO2, and improve overall health and quality of life (1–5). Additionally, the implementing company concluded that the trees planted near residential areas can significantly reduce energy needs for air conditioning and heating, leading to an average cost decrease of 30% during summer and winter (1, 2).
Volunteers participating in the project received a "tree certificate," signifying their commitment to planting and adopting a tree (7). In this initiative, volunteers were also tasked with monitoring the growth of their adopted trees to ensure their health (1–6).

The municipal real estate company Higab partnered with The Foodprint Lab Architects, an architecture firm specialising in food system design, in a three-year pilot project to create urban farms in three of their properties in Gothenburg. The Foodprint Lab designed the urban farms based on the conditions of each property and connected Higab with potential farmers. The urban farms are located at Slakthuset (an old industrial area), Kviberg (by an empty building undergoing renovation) and Musikens hus (an old building used for music events and a restaurant). The farms are established in unused, mostly grey areas such as parking lots. In all sites, the farming is run by local farming associations; some sell vegetables on site and in Kviberg, there has also been a commercial production of vegetables. Sustainable food production, entrepreneurship opportunities, a nicer and safer environment, and the promotion of biodiversity are highlighted as benefits of the project. In total, about 50 different plant species are found across the locations. The establishment of the urban farms was part of the Grow Gothenburg project within the Sharing Cities Sweden program, which provided some of the funding [Ref. 1-5, 7].

The pilot project in Bairro Padre Cruz, Carnide, Lisbon, is a groundbreaking initiative aimed at enhancing women's safety in public spaces and improving access to public transport. Launched in June 2024, this project stems from extensive consultations with local women to address their specific security concerns (Ref1). It involves strategic interventions like better lighting and the relocation of bus stops to safer areas, ensuring a more secure environment for women (Ref4). A key element of the project is the greening of the area through tree planting and the creation of more harmonised public spaces, contributing to a more pleasant and welcoming neighbourhood (Ref2). Funded by the Recovery and Resilience Plan (RRP), this initiative aims to foster greater inclusivity and safety in urban design, with completion expected by 2025 (Ref4).