Expected improved soil quality

The Grand Parc des Aygalades project involves the creation of a 14-hectare metropolitan park (connecting Aygalades Park with Bougainville Park and François Billoux Park) that will connect the northern neighbourhoods of Marseille to the port located further south (Ref 1). This project is part of the green conversion of Marseille's northern districts, historically among the most disadvantaged areas in France (Ref 1). The Grand Parc des Aygalades project will enhance the city's greenery, reduce flood risks, create cool zones, restore and develop biodiversity, and significantly improve residents' quality of life and air quality (Ref 1, Ref 2). The environmental and social challenges include reconnecting the populations of these neighborhoods to green spaces, services, education, sports opportunities (Ref 2).
The park project includes redesigning urban infrastructure to improve rainwater absorption and reduce flood risks, addressing the issue of impermeable and artificialized soils that exacerbate flooding during heavy rainfall (Ref 1). It also involves renaturing a 17-kilometre-long stream currently buried under railway tracks, improving flood management and rainwater drainage (Ref 1, Ref 4). The project will also convert a heavily degraded former industrial site, requiring the rehabilitation of polluted soils (Ref 1). Additionally, creating green corridors aims to mitigate the heat island effect, particularly severe in these northern districts due to the high concentration of buildings and concrete surfaces, and the lack of green spaces. Public participation will be encouraged through information meetings, thematic workshops, and an online platform for submitting ideas and feedback (Ref 4).

The "Plan Arbre" is a tool for ecological planning and renaturation aiming to plant 308,000 trees between 2023 and 2029, sourced from the municipal nursery with seeds purchased from local suppliers (Ref 1, Ref 2). In 2023, 14,922 trees were planted, with plans to double this number in 2024 (Ref 1). The project addresses the loss of 50% of Marseille's natural spaces over the past 75 years, aiming to reverse this trend and reintroduce nature into the urban environment (Ref 2). It also tackles issues like drought and heatwaves, particularly in summer, by using trees and shrubs to cool the air, restore biodiversity, reduce air pollution, and enhance public spaces while absorbing CO2 (Ref 2).

The plan is divided into two phases. Phase I focuses on planting in Marseille's 58 parks and 273 squares and gardens, as well as around childcare centres, schools, socio-cultural centres, and sports facilities (Ref 2, Ref 3). From 2020 to 2023, various improvements were made, including playground renovations, installation of misting systems, automatic watering, and the creation of a CrossFit area (Ref 3). Phase II will involve identifying major boulevards, avenues, and streets lacking trees to enhance the urban canopy (Ref 2).
A diverse range of tree species were selected for their drought resistance, water efficiency, and ability to attract biodiversity (Ref 2, Ref 3). The project also focuses on increasing biodiversity and managing invasive species through natural methods to protect trees from pests without chemicals (Ref 3). Furthermore, the initiative includes de-impermeabilizing soils and implementing a smart irrigation system with tensiometric sensors, developed with the start-up GreenCityZen, which has saved 66% of water in two years (Ref 3). The Plan Arbre also promotes citizen participation, with 23 parks selected for community gardening projects, where ten winning associations will receive plants from the municipal nursery (Ref 1).

The project, implemented by the municipality of Cagliari, involves the creation of a new garden in 2021 on Via Eroi d’Italia, in the Pirri municipality, located about 5 km from the center of Cagliari. This initiative is part of a broader effort to reclaim degraded urban green spaces. The garden spans approximately 900 square meters and was previously an unused lot serving as a parking area. Its transformation required substantial groundwork, including soil scarification and leveling, to prepare the area for its new purpose. The garden is now enclosed, with pedestrian access via two gates leading to a paved walkway.
Inside, the garden is divided into two main sections: a children's play area and a landscaped green space. The play area covers about 100 square meters and features durable artificial grass, swings, a spring toy, a universally accessible table, a children's table, benches, and a multi-compartment recycling bin. The green space, approximately 200 square meters, is planted with low-water-use grass and surrounded by drought-resistant plants like albizia, oleander, and lantana, chosen for their low water consumption and resilience to environmental stress. An underground irrigation system, linked to a 5,000-liter water tank, ensures efficient water use.
The remaining 600 sqm outside forms a parking area with 1 disabled space, 2 motorcycle spaces, 1 bicycle rack, and 15 car spaces.
The garden also incorporates sustainable elements, such as LED lighting for energy efficiency and a mural by renowned Sardinian artist Manu Invisible, depicting sunlit forest undergrowth in shades of green. This project responds to citizens' requests and prioritizes resource efficiency by reducing hazardous substances and minimizing waste. The materials used, including recycled plastics, and the selection of plants were chosen to match local ecological conditions, enhancing the garden's sustainability and reducing its environmental impact (Refs. 1, 2, 3, 4 & 5).

The first medicinal plant library in Martinique was created by the Ypiranga Martinique association, which inaugurated the project in 2019. The initiative was developed to preserve and revitalize traditional knowledge of medicinal plants in Martinique, integrating agroecology , modern scientific understanding, and ancestral practices.
The project is located on land provided by the municipality in the Tivoli neighborhood, and it serves as an educational resource, a functional pharmacy, and includes a small shared vegetables garden. Visitors, local residents, and researchers can access information on over 150 native Caribbean plants and their medicinal properties. The site includes two educational trails: one following the river that crosses the garden and a sensory trail designed to help visitors "reconnect with nature." Each plant is identified with information boards detailing its medicinal uses, including whether these uses are scientifically validated.
The project also aims to address social exclusion by offering reintegration workshops to troubled teenagers and the unemployed.
The project was financed through a combination of sources: an EU-funded call for projects, a crowdfunding campaign, and regional and national public subsidies.
As a result of its success, in 2021 the initiative was formally replicated with the support of the Caribbean Interreg "OSAIN" project, which led to the creation of 14 additional plant libraries in schools and public spaces. Volunteers and community-based efforts continue to sustain the project, and it has become a model for similar initiatives. (Ref. 1,2,4,5,6,7)

The project at Poetto Beach in Cagliari, Italy, implemented by the municipality of Cagliari, began in 2022. It focuses on protecting and restoring the dune system while raising public awareness about the importance of preserving the coastal ecosystem. The project recognizes the delicate balance between environmental preservation and public enjoyment of Poetto Beach.
Key activities include installing barriers and signs to prevent trampling and littering, modifying beach access points to reduce erosion, and implementing significant interventions to restore the beach. These interventions involve strengthening anti-erosion measures with dune confinement and sand retention systems, as well as creating natural barriers (natural repopulation of native plants ) to protect the seashore. Public education initiatives aim to encourage responsible beach use and enhance understanding of the dunes' fragility. Additionally, new access walkways will be installed, and existing ones will be improved, including the creation of four wheelchair-accessible pathways to the water, designed for easy entry.
This comprehensive plan for protecting and enhancing Poetto's environmental resources is valued at €945,000 and is funded by the European Regional Development Fund.
Overall, the goal is to enhance environmental quality, promote sustainable beach use, and prevent both natural and economic losses. By balancing enjoyment of Poetto's natural resources with their protection, the project aims to ensure the long-term preservation of this valuable coastal area (Ref. 1, 2 & 4).

Maya’s Farm is a small, CSA (Community Supported Agriculture) sustainable urban farm located in Phoenix, Arizona, where urban development has limited farmland availability. In 2020 alone, Phoenix lost nearly 200 acres of farmland to urban sprawl, putting farms like Maya’s at risk. The farm faced potential closure until the City of Phoenix intervened, providing funding through the Farm Preservation Program, which established the city's first urban agricultural conservation easement. Maya's Farm strives to inspire a local appreciation for sustainable food and to bring renewed value to local food systems.
The farm’s mission is to provide accessible, fresh, locally grown produce to the community while promoting awareness of healthy, sustainable food practices. Through its CSA program, members receive a weekly produce box and have opportunities to come together, honor food traditions, and share stories over locally harvested food. As a CCOF (California Certified Organic Farmers) certified organic farm, Maya’s Farm is committed to organic practices that exclude GMOs, nurture the soil, foster biodiversity, and innovate growing systems. These methods result in healthy soil and cleaner air, contribute to carbon sequestration, and support critical wildlife habitats.
To broaden educational outreach, Maya’s Farm offers several programs that promote sustainable food practices, including its CSA program, an edible classroom series, and a partnership with Arizona State University (ASU). Through this ASU partnership, students gain hands-on experience by participating in daily farm operations.
Building stronger community connections is another cornerstone of Maya's Farm’s work. The farm collaborates with local restaurants, farmers' markets, and community groups to expand its impact. Maya’s Farm, ASU, and Arizona Sustainability Alliance launched an agrivoltaics project with solar-shaded crops. (2, 9, 11, 13, 15)

The Bela Flor Respira (BFR) project, also known as "ComBOA", is an urban agroecology initiative located in the Campolide neighbourhood of Lisbon, Portugal. This project exemplifies a transformative approach to community development and environmental sustainability by repurposing a neglected urban space into an agroforest. Launched in 2018 by the NGO Circular Economy Portugal, BFR engages local residents of the neighbourhood, from children to the elderly, volunteers, and academic partners, in creating a regenerative space that combines food production with social interaction (Ref 1). The project emphasises the co-production of public policies, fostering social cohesion through collective intelligence and civil society entrepreneurship (Ref 1). BFR’s innovative approach integrates syntropic agriculture, blending fruit trees, vegetables, and native species to create a resilient ecosystem that supports both the environment and the community. Through this initiative, BFR not only enhances urban green spaces but also strengthens community bonds, making it a model of sustainable urban development (Ref 3).

In 2022, the municipality of Cagliari launched a project to revitalize Viale Trieste, one of its avenues, by redesigning its roads and pedestrian areas and adding new green spaces. The project covers approximately 1,300 meters and 36,500 square meters, and will be completed in two phases, each focusing on different sections of the avenue. With a budget of 12 million euros, funded by municipal, national, and EU resources, the aim is to transform Viale Trieste into a vibrant, accessible, and attractive space for everyone.

The renewal will introduce new green spaces and improved drainage systems to enhance soil permeability. As part of this, some trees will be relocated to other areas of the city to address root issues and improve survival rates. Dead or unstable ficus trees will be removed, while 79 new trees will be planted. Older ficus trees will be relocated to city parks, with younger ones planted along the avenue to prevent pavement damage and promote sustainability. The project also includes upgrading water supply and drainage systems to manage stormwater more effectively, reducing the risk of flooding and improving sustainability. Public lighting will be modernized, with new street lamps and dedicated lighting for pedestrian and bicycle paths to make the area safer and more welcoming after dark.

However, the community has expressed concerns about the project, citing safety issues, delays, disruptions, and poor communication from officials. There is also significant opposition to replacing the historic ficus trees, valued for their environmental and historical significance, with Chinese pear trees and younger ficus (Refs. 1, 2, 3, 4, 5, 6, 11, 16).

FoodLink, a network for food transition in the Lisbon Metropolitan Area (LMA), aims to create sustainable, competitive, and resilient agri-food systems closely integrated with regional and local spatial planning. The network's goals are to promote food security, economic and energy efficiency, environmental sustainability, and socio-territorial cohesion by 2030. The network seeks to ensure that by 2030, 15% of the metropolitan area's food supply is secured locally through sustainable production methods, innovative solutions in water management, soil conservation, climate adaptation, and low-carbon distribution networks involving community gardens, urban allotments, and agricultural spaces within the Lisbon Metropolitan Area. (Ref 2)

The "Line Park" project in Belgrade aims to create a continuous green belt spanning 4.6 kilometres and covering over 48 hectares. As such, the project will revitalize the former railway corridor from "Beton Hala", just below the Belgrade Fortress, to the Pancevac Bridge. Inspired by notable urban parks like New York's "High Line", Moscow's "Zagrađe," and Toronto's "Rail Corridor," it will become a major recreational destination and also help to alleviate the pressures from the city's heavy air pollution and summer heat (Ref. 5, 6).
The park will be divided into ten thematic sections dedicated to aromatic plant and flower gardens, urban gardening and beekeeping, sports facilities, a newly built university campus and more. Additionally, there will be an amphitheatre and facilities for outdoor education. To further integrate green infrastructure, new buildings will have green roofs and walls (Ref. 2,5). Ultimately, the park integrates a number of amenities into the entire city.
The development of the park also introduced innovative co-creation mechanisms in terms of governance and planning. Since Belgrade is part of the multinational CLEVER Cities Initiative, the city's Secretariat for Environmental Protection suggested the use of the site as a pilot test for introducing nature-based solutions in urban planning and with diverse stakeholders' input. Several workshops, focus groups, and consultations took place between 2019 and 2021, which facilitated the diversity of ideas that have been adopted into the official construction plan (Ref. 1, 2). Despite these successes, civil society groups raise concerns over the extraordinary cost of 70 million euros, displacement of Roma communities and the interest of real estate developers that may undermine the project's original cause (Ref. 3, 8).