Citizens or community group

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).

Dudley, a historic market town in England and part of Birmingham's metro area, is reported to have some of the lowest rates of public access to nature in the country, ranking in the bottom 10% of governmental statistics for available greenspace relative to population density (Ref 1). To address this issue, the Dudley's Path to Nature Recovery project was launched in 2024 by the Birmingham and Black Country Wildlife Trust (BBCWT). The initiative aims to reduce inequalities in access to nature and create a greener future for local residents (ibid.).
Funded by the West Midlands Combined Authority, the project seeks to reconnect local communities with nature through five key activities: conservation work, community engagement, citizen science, partnership development, and the creation of new walking routes (Ref 1, 2, 3).
Among the project's activities, conservation efforts will include community engagement and focus on woodland improvement, heathland creation, and more. Additionally, the project will bring together key partners and community groups to explore collaboration models and identify potential sites for joint projects. Lastly, new walking routes will be created across the project’s landscape (Ref 1).

The Juan Angola River is an urban channel included in the system of rivers and channels of Cartagena, and it connects the Ciénaga de la Virgen wetland and the Bay of Cartagena, facing similar issues as the Cienaga de la Virgen such as illegal occupation of its shores, illegal waste dumping, deforestation of mangroves, and pollution. The recovery plan for the Juan Angola River is led by the EPA Cartagena (Environmental Protection Agency), with the support of other institutions, aiming to restore the Juan Angola’s ecosystem. This includes targeting the mangrove forest, dredging the natural channel, and delineating buffer zones with urban infrastructure to create public recreational spaces. The activities involve relocating people illegalling cupping informal settlements from the river shore, moving an existing bridge (the Benjamín Herrera bridge) which obstructs the current, recovering the low tide and riverbed areas, building pedestrian paths, clean the riverbank, recover mangrove areas and establish programs of education and environmental awareness (ref 1 and 2).

Phoenix faces substantial challenges related to extreme heat, air quality, and social inequity (1-11). The Phoenix Tree Equity Pledge, launched in 2021, is a comprehensive city-wide initiative focused on addressing urban tree inequity and reducing the effects of extreme heat, especially in communities most vulnerable to these conditions (1-12). Partnering with American Forests, the country’s oldest conservation nonprofit, the initiative aims to achieve “tree equity” by 2030, ensuring all neighborhoods receive the benefits trees offer (1).
To reach this goal, the city will focus on enhancing tree coverage in underserved neighborhoods through the development of a Residential Tree Equity Accelerator, which plans to plant 20,000 trees across 25 neighborhoods by 2030 (1-12). By utilizing the Tree Equity Score developed by American Forests, the city can monitor progress, identify areas of need, and measure the impact of these projects (2-4, 9, 11).
To foster public engagement, the initiative will collaborate with residents, businesses, and local organizations to support tree-related projects, raise awareness of the benefits of trees, and promote tree stewardship (1, 4, 15). Additionally, the project aims to create green opportunities within the community by establishing supportive policies and regulations for tree planting and care and by creating pathways to green jobs (1, 7-9, 13-14). Recognizing that heat affects communities unequally, the Tree Equity Pledge seeks to increase canopy coverage in targeted neighborhoods, improving air quality, reducing the urban heat island effect, and enhancing overall community health (1, 7-9, 13-14).

The Three Mile Creek Greenway Trail project aims to transform the existing creek into a valuable community asset by developing a multi-use greenway trail (Ref 1). This greenway will connect various parts of the city through walking and biking paths, linking neighbourhoods, parks, and commercial districts while providing access to unique natural areas (Ref 2). The creek having been adandonned for decades (Ref 5), the initiative seeks to turn 3 Mile Creek (3MC) into a vibrant natural corridor that fosters recreation, education, and economic activities (Ref 1, Ref 2). The project aims also at reducing pollutants in the waterway, restoring natural stream channels, and maintaining flood protection (Ref 1).
The 3MC Greenway Trail is expected to become a key feature of Mobile's urban landscape, offering numerous benefits. These include enhancing community health, both mental and physical (Ref 2), and stimulating the local economy by increasing property values, tax revenues, and opportunities for recreation-related businesses and job development (Ref 2). Additionally, the trail will improve community connectivity by linking neighbourhoods, parks, and schools, thereby fostering a stronger sense of community and better access to public spaces (Ref 2). Lastly, the project will contribute to environmental restoration through stormwater management, pollution reduction, and natural habitat preservation (Ref 2).
The greenway is part of a plan to restore the health of the Three Mile Creek watershed and is the first major piece of a long-term Mobile Greenway Initiative (MGI) (Ref 4).

Spaces of Opportunity is an initiative created by several organizations in Phoenix, that aims to bring food security and sustainability to the south Phoenix community. The initiative aims to reach its goals through its community garden that incorporates 19 acres of barren land (dessert) that can be used by locals for growing food and earning an income while providing the community organically grown produce. The mission is to enable all South Phoenix families to have affordable access to healthy food, active living and healthy roots of their cultures (1, 2, 4, 6, 8).
The initiative started in 2011 when several local actors formed a coalition with a shared vision of improving well-being by addressing the natural, built, and social environments. Spaces of Opportunity is the only local food system of its kind in the Phoenix metropolitan area, and unique in the country for the diverse strengths of the committed partner organizations and their shared vision to bring food security, build sustainability, and cultivate community. (8)

The Sacred Heart Church, a historical landmark in Detroit's Eastern Market since 1875, faced persistent stormwater and surface flooding issues. The church's parking lot, once marked by cracked concrete and stagnant water, has been transformed through an innovative Green Stormwater Infrastructure (GSI) retrofit. GSI leverages natural processes to manage stormwater, using plants to absorb, retain, and slow runoff. This retrofit, a collaboration between The Nature Conservancy and the parish, stands as one of Detroit's largest GSI projects at a faith-based institution. By introducing bioretention gardens filled with native plants, the project manages runoff from 1.4 acres of impervious surfaces and diverts 1.5 million gallons of water annually from the sewer system. This green space not only mitigates flooding and reduces combined sewer overflows (CSOs) but also provides a cooling effect, enhances community recreation, and significantly cuts the parish's drainage charges by 49%.(Ref.1,2,3)

Lomas are endemic seasonal ecosystems found in Peru and Chile. They provide a variety of benefits such as soil stabilisation, air purification, recreational spaces, water retention, and are habitats for endemic and threatened species (Ref 7). They are of great ecosystem value to the city of Lima, as green areas have been reduced in the urban area, occupying up to 24% of urban green ecosystems. These ecosystems are threatened by unplanned urban growth, traffic, pollution and lack of government regulation. Given this context, Eab Lomas is a project that focuses on the conservation, management and rehabilitation of the ecosystems found in the Lomas of Lima (Ref 1, 2, 3, 4, 5). It focused on 4 lines of action: conservation of Lomas' ecosystems; implementation of territorial planning; economic diversification focused on the conservation and recovery of vegetation through low-impact recreational activities; and management of water resources (Ref 1, 2, 3, 4).