Preservation of natural heritage

The Mobile Tree Trail is a nature-based solutions (NBS) initiative aimed at preserving Mobile, Alabama’s urban forest while celebrating its cultural and ecological heritage (Ref 1, Ref 2). First established in the early 1990s by volunteers, the original trail featured 24 iconic trees, selected for their historical significance, environmental value, and beauty (Ref 1, Ref 2). Over the years, some trees were lost to development and storms, and the trail faded into obscurity (Ref 1, Ref 4).
From 2021, the Mobile Tree Commission, with support from The Nature Conservancy, is leading efforts to revive the trail (Ref 3, Ref 6). Activities include reviewing past entries, opening public nominations, and selecting new trees that best represent Mobile’s identity (Ref 3, Ref 4). The project emphasises inclusivity and public participation, welcoming volunteers and local input to shape a trail that evolves with the city (Ref 4, Ref 6).
Mobile faces environmental threats such as hurricanes, urban expansion, and loss of native tree cover (Ref 1, Ref 6). The revitalised trail helps address these challenges by promoting awareness, conserving old-growth specimens like the 300-year-old Duffie Oak, and maintaining vital green spaces (Ref 4, Ref 6).
The Mobile Tree Trail blends education, tourism, and conservation, enhancing urban resilience while telling the city’s story through its trees (Ref 3, Ref 6).

The stretch of the Great Lakes basin ecosystem from southern Lake Huron through western Lake Erie forms a unique urban refuge where life thrives with beauty and resilience. Known as Metropolitan Detroit, this region is where the Community Foundation for Southeast Michigan and many partners are working to create The Great Lakes Way by connecting 160 miles of greenways and 156 miles of water trails (1).
The vision for the Great Lakes Way project is to ensure that all residents and visitors of southeast Michigan—people of all ages, backgrounds, ethnicities, abilities, and interests—feel connected to the water resources, welcomed on its trails, and able to enjoy the benefits and opportunities these access points provide (1). To bring this vision to life, the project plans to link 160 miles of greenways and 156 miles of blueways, connecting people to a range of world-class freshwater, wildlife, and recreational opportunities. These include fishing areas, bird migration pathways, parks, working waterways, preserved woodlands, and restored wetlands (2).
The Great Lakes Way project connects existing assets, supports accessibility and equity, and promotes the Great Lakes Way to both residents and visitors through marketing and communication efforts (2). There are 26 points of interest that will serve as connection hubs along the Great Lakes Way (2). In Detroit specifically, the focus is on connecting 13 culturally or historically significant destinations, as well as locations known for their environmental and ecological importance or as regional landmarks (2).
Rich in world-class fisheries, migratory flyways, parks, urban centers, small towns, preserved old-growth woodlands, and restored wetlands, the Great Lakes Way offers unique experiences that can only be found here. By uniting the natural and cultural assets the Great Lakes Way designation aims to emphasize and expand the essential linkages needed to further connect this remarkable region. (2,3)

For thousands of years the Rio Salado, also known as the Salt River, and its larger mainstem, the Gila River, served as an important perennial source of life and growth for indigenous people residing in central Arizona, including the Akimel and Piipaash (3). Today, the Salt River is an ephemeral river corridor connecting diverse urban communities across an expansive and growing Maricopa County (3). While the river is now typically defined by intermittent flow as a function of water conservation and distribution in an arid urban climate, it also has powerful flows during the Arizona monsoon season providing a diverse and unique ecosystem for the region (3). To foster the health of the River, a regional multi-decade project was initiated in 2018 called Rio Reimagined, which includes six cities and two tribal communities (1). Rio Reimagined is a planning initiative in a very early concept stage, centered around the mission to support and enhance this treasured river corridor (3). The goals of Rio Reimagined consist of connecting communities, Equitable & Sustainable Development, and Restoring and Revitalizing Healthy Rivers (3). As part of the Rio Reimagined, the City of Phoenix founded a collaborative project called Rio PHX that will help promote a 20-mile Rio Salado (Salt River) corridor as a local and regional destination that attracts positive investment for the benefit of existing/future businesses, residents, and tourists (1). The final aim with this project is to improve health outcomes for existing and future residents by address outstanding needs in the area and create opportunities for housing, employment, recreation, art, and ecological restoration (1). From May 2024 to May 2025 Rio PHX will engage in creating a community profile, an existing conditions assessment, community engagement & visioning, developing implementation strategies and drafting the master plan (1). Public hearings and final plan adoption are set to take place in fall 2025 (1).

Located in the municipality of Morne Rouge, the Domaine d’Émeraude was once an agricultural site but was transferred to the Martinique Regional Natural Park (PNRM) in the early 2000s. It underwent significant renovations in 2005 to transform it into a sanctuary for Martinican biodiversity, reflecting the need to protect and conserve the island's unique ecosystems. In 2011, it opened its doors to the public, serving as an important educational resource that raises awareness about the island's historical, natural, and cultural heritage (Refs 4, 7, 8).
Today, the site encompasses 25 hectares protected from anthropogenic pressures and is primarily characterized by a humid tropical forest environment, which makes up 80% of the area (Ref 7). It is home to over a hundred native species (Ref 4) and offers nearly 4 kilometers of walking trails accessible to both adults and children, complete with recreational stops and educational amenities.
The Domaine d’Émeraude was designed to enhance the conservation of native species while developing sustainable economic activities that benefit the local community. Moreover, the site emphasizes the well-being that forested areas provide to visitors, highlighting that "the air can be heard, the smells can be savored, and the sounds can be experienced. The freshness of the place is a source of change and relaxation..." (Ref 4).

"Urban Natural Area Ciric" is an initiative aimed at designating the forest and lakes of the Ciric area, located on the outskirts of the city of Iași, as an Urban Natural Area. To achieve this goal, the initiating organizations—NGO Civica and the Ornithological Association of Iași (SOR)—have developed a comprehensive report focused on the Ciric natural area, which monitors species and habitats while identifying pressure points on biodiversity and necessary conservation actions, as well as the benefits these areas provide.
In the Ciric area, various flora and fauna species have been identified, with some holding high protection status (14 bird species) or being of community importance and conservation interest. However, this ecological richness faces threats, as factors such as rapid urbanization, water pollution, and waste disposal have been identified as significant risks to the ecosystems.
In response to these challenges, the NGO aims to collaborate with the municipality to create protective municipal laws that will not only recognize the area as an Urban Natural Area but also ensure its inclusion in development plans. This partnership seeks to establish regulatory measures and strategies that will safeguard and enhance the biodiversity and ecosystems of Ciric. Additionally, the organizations have highlighted the social and physical benefits of the area for residents, including flood regulation and prevention, pest control, provision of clean air, and recreational and scientific opportunities.
To further raise support and awareness for their efforts, SOR and Civica conduct guided tours, educational workshops, and photographic exhibitions. They have also set up two informational panels in the area that highlight the biodiversity of Ciric. Furthermore, the two NGOs have partnered with regional organizations to create the "Rețeaua națională de arii naturale urbane" (The National Network of Urban Natural Areas) and have received funding from the EEA Grants. (1-8)

Martinique is a biodiversity hotspot, home to over 1,500 endemic plants, 70% of which are under threat from human activities. In response to these pressures, the Péyi Vert [Green Country] initiative was launched to plant endemic trees and strengthen the island's biodiversity. Beyond simply preserving species, these trees are crucial in maintaining healthy ecosystems, as they provide essential services such as carbon sequestration, shade, food for human consumption, soil decontamination, pollination, and protection against coastline erosion.
Launched in June 2020 by Entreprises et Environnement (EE), a not-for-profit business association representing 80 Martinican companies, the Péyi Vert initiative aims to plant 1 million native trees (either Martinican or Caribbean) over five years. It can be seen as a Martinique-wide strategy to adapt to and mitigate climate change. Péyi Vert facilitates connections between people who want to plant trees and Martinican companies that serve as financial sponsors. The initiative emphasizes conserving natural heritage by planting endangered species, as well as promoting native species that, while not necessarily threatened, provide valuable ecosystem services or contribute to biodiversity restoration.
Between 2020 and 2023, EE reported planting 50,000 trees (Refs 1, 4, 6, 7). Although individuals can make donations, Péyi Vert primarily seeks funding from companies looking to offset their carbon emissions or enhance their Corporate Social Responsibility (CSR). To achieve its goals, the initiative mainly collaborates with municipalities, companies, and farmers (Ref 3).

The rate of deforestation in the Brazilian Legal Amazon in 2023 was consolidated at 9,064 km2. Initiatives that promote forest restoration in this biome are emerging to overcome this scenario. One such initiative is Floresta Productiva which aims to reforest more than 200 hectares of degraded land in the southwest of the Brazilian Amazon, known as the ‘arc of deforestation’ (1). Led by the Instituto Socioambiental in partnership with the NGO Rioterra, it focuses on creating and disseminating native forest restoration models that combine ecosystem recovery with income generation for rural producers in Porto Velho (2). By fully integrating local communities, the project promotes traditional agroforestry practices (muvuca) and trains communities to maintain the planted land. This not only restores the forest but also provides economic benefits through the cultivation of timber, fruit trees and other species (2), strengthening sustainable agriculture, breaking the cycle of deforestation and restoring deforested areas through various native species grown in nurseries (1). The project is being developed in the cultivation area of the Amazon Bioeconomy Centre (CBCA), from 2023 to 2025, where it will directly benefit the rural community of Vila Nova de Teotônio (3).
The project started in 2019 and has impacted other communities in the area, such as the communities in Nova Mutum Paraná and Ji-Paraná (1). During these years, more than 123,000 trees have been planted in agroforestry on about 110 hectares of land, and edible forests have been created. Since 2022, a new planting phase has been underway, to plant more than 100,000 trees of 87 native species on 40 hectares of degraded forest (4). In conclusion, this project focuses on the development of agroforestry in the face of widespread monospecific soybean fields and intensive cattle ranching (3); the creation of edible forests (3); and the restoration of forest cover to ensure the long-term resilience of the forest (3).

The John Michuki Memorial Park was transformed from a vast dumpsite in 2008 and established in honor of John Michuki, the Environment Minister during the Kibaki administration, in 2012. Michuki garnered admiration and accolades for his enthusiasm and determination to clean and preserve the environment (Ref 1, 2). Situated along the Nairobi River, the park serves as a historically rich recreational facility (Ref 3).
However, several issues arose after the park was transferred to the county administration in 2013 (Ref 2). A section of the Nairobi River flowing through the park experienced severe environmental degradation due to illegal discharges and poor waste management, negatively impacting the riparian ecosystem and biodiversity (Ref 4). Additionally, the park became a refuge for drug users, street children, and thieves, with stray dogs posing safety threats in the area (Ref 1, 2).
As the first project within the Cleaning Up Kenya Campaign, the restoration of Michuki Memorial Park was launched in 2020 by the government (Ref 5). The park is now managed by the Kenya Forest Service (KFS) following a directive from the national government (ibid.). With funds from the treasury, a perimeter fence was erected, a 2.4 km walkway was constructed, and 4,200 seedlings and 6,357 indigenous trees were planted, along with the establishment of a nursery (Ref 1, 6). A total of 20,000 tons of solid waste were removed (Ref 6). Additionally, a community forest association was formed to ensure community engagement (Ref 2).

The riparian forest of Montgérald, through which the “Monsieur” River flows, is located within Fort-de-France and boasts rich biodiversity, featuring around 100 species of shrubs and trees and about 30 animal species, including 16 types of birds. It is one of the last remnants of the mesophilic forest type and the only example in a French peri-urban setting. This unique ecosystem is recognized as a Natural Area of Ecological, Faunal, and Floral Interest (ZNIEFF) and a Classified Wooded Area (EBC), underscoring the need for conservation efforts.
Covering nearly 21 hectares, this site offers ecological benefits like air quality improvement and temperature regulation, providing a "fresh air island" near the city center. However, it faces significant challenges, including flooding caused by climate change and heavy rains, which exacerbate erosion along the Monsieur River. The area is also threatened by invasive alien species, making conservation measures even more crucial.
Since 2015, the municipality of Fort-de-France, along with project partners, has been working on developing this natural space for both conservation and public engagement purposes. The most recent actions occurred in 2020, including riverbank restoration, clearing invasive species, and creating walking paths and educational installations. Additionally, the project features an awareness campaign targeting local schools. The ongoing initiative aims to merge biodiversity conservation with community recreational use and environmental education, ensuring the resilience of this vital ecosystem against the impacts of climate change. (Refs. 1, 2, 3)

The Stora Amundö and Billdal archipelago nature reserve is in the southernmost part of the City of Gothenburg. The proximity to the city makes it a popular recreational destination, with about 73000 visitors each year. In 2018, the area was protected as a nature reserve to preserve its recreational, natural and historical values. The status as a nature reserve prohibits any exploitation and other harmful activities in the area. The area of the reserve is 1103 ha, of which 259 ha is land area and the rest is water [Ref. 1-3]. The management of the reserve includes promoting recreational and educational activities by creating new entrances, paths and signs, as well as holding guided tours. The management also includes restoring and improving terrestrial ecosystems such as grasslands through mowing and grazing and deciduous forests through selective clearing. A wetland has been restored to promote biodiversity further [Ref. 2, 4]. The reserve was created and is managed by the City of Gothenburg, the process of creating it involved consultation of stakeholders such as land owners, government agencies and NGO's [Ref. 1]. Some local landowners disagreed with the borders of the nature reserve having an impact on their land, leading to an appeal that was ultimately denied [Ref. 5, 6]