More sustainable tourism

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 Lower Perdido Islands – Bird, Robinson and Walker Islands – are located in the Perdido Pass, in Orange Beach. The area is a popular destination, attracting many visitors due to its blue-green water and diverse wildlife, which, however, leads to erosion from boat wakes and marine debris. Its popularity impacts these wildlife habitats, including the seagrasses, marsh and forests which provide habitat for nesting birds and nurseries for local fish. Therefore, the Nature Conservancy, the City of Orange Beach, Moffatt & Nichol, and Olsen Associates Inc. started working together in 2017 to create a conservation management plan for the Perdido Islands, as well as develop some restoration initiatives to support this critical habitat for the future [1,3]. This Lower Perdido Islands' restoration project is part of a larger Perdido Bay Watershed restoration plan [2]

The Thalangama wetlands are part of a network of wetland ecosystems around Colombo city that spread over 20 km2 and provide critical life support to the city. These ecosystems keep people safe from floods, cool the air, filter polluted water, provide food and medicines, and fight climate change (10). These wetlands have become an environmental protection area and a biodiversity hotspot in a rapidly urbanising environment, as they host an array of plants and animals, including the endangered fishing cat and otter (5, 10). In 2007, Thalangama Lake and its surroundings were declared an Environmental Protection Area (EPA) under the National Environmental Act (4, 5). This protected area covers approximately 118 hectares (4) and includes two man-made reservoirs: Thalangama Tank (11 ha) and Averihena Tank (3.2 ha), located just 300 meters apart (5). The area hosts floating and rooted plants, scrublands, and trees that provide habitat to up to 100 species of migratory, resident, and endemic birds throughout the year. In addition, the area supports 30 species of dragonflies, 12 species of reptiles, 10 species of mammals, and 15 species of freshwater fish (1, 4). Since the lakes and their surroundings were declared an EPA, only limited uses are permitted, such as traditional fishing and rice cultivation (4, 5). The lakes are also important for floodwater retention and have high scenic and aesthetic value, attracting many visitors, and scientific and educational activities (5, 13).
However, due to the area's rapid urbanisation, land values have increased significantly, leading to excessive landfilling and the reclamation of paddy lands for housing. This is compounded by the indiscriminate disposal of garbage and construction waste and the spread of invasive species (5). These challenges have also led to the engagement of surrounding communities in managing and maintaining it (11).

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)

Sri Lanka faces multiple natural hazards, including tropical storms, flash floods, and landslides. As the country's urban population has grown, development projects have encroached on wetlands, compromising their natural flood protection, air and water purification, and carbon storage capabilities. Additionally, hilly regions are at risk of landslides, particularly during the monsoon season, posing significant threats to vulnerable communities (4).
To address these challenges, the World Bank and the Sri Lankan government collaborated on the Metro Colombo Urban Development Project. This initiative focused on nature-based solutions (NBS) as cost-effective and sustainable approaches to risk management (4). By strengthening natural processes and ecosystem services, the project aimed to mitigate hazards such as floods, erosion, and landslides (4). Technical assessments by the World Bank highlighted the importance of wetlands in flood protection, leading to efforts to protect and restore 20 square kilometres of freshwater lakes, wetlands, and swamps (1, 4).
The project supported the Sri Lankan government in reducing flooding in the Colombo Water Basin and enhanced local authorities' capacity to manage infrastructure and services. It prioritised metropolitan investments to mitigate the physical and socioeconomic impacts of flooding and aimed to build long-term capacity for urban management and local service delivery (6).

The Cagliari Canal project is an initiative aimed at revitalizing and transforming the urban and natural landscape of the Cagliari Metropolitan Area in Sardinia. The project is rooted in the city's strategic metropolitan plan and seeks to restore and enhance the navigability of the Terramaini-La Palma canal, which had become disused and neglected over time​ (3,4). The primary goal of the Cagliari Canal project is to develop a connected, innovative, and sustainable urban environment by re-establishing the canal as a green and blue infrastructure​ (2). It aims to provide alternative, sustainable mobility options, improve connectivity between municipalities, and enhance the natural and urban environments. It strives to foster a sense of community by creating a shared space for residents and integrating modern amenities that align with environmental sustainability (1,4). It involved a highly participatory process, emphasizing community involvement from the initial planning stages. The Metropolitan Authority of Cagliari, in collaboration with local stakeholders, launched a series of consultations to gather public input on the canal's design and function​(3). These consultations were part of a broader initiative called LabMet, the Metropolitan Laboratory for Innovation, which facilitated the collection of ideas and feedback (1). The project was partly developed in response to the increasing environmental challenges faced by Cagliari, including the need to adapt to climate change. The canal's revitalization is seen as a key measure for enhancing the city's resilience to climate-related risks, such as flooding and heat waves​(1). By restoring the canal and its surrounding areas, the project aims to mitigate these risks through improved water management, reducing pollution, and the creation of green spaces that can absorb excess rainwater and provide cooling effects​ (2)

The Bee Park Molentargius is a project located in the Molentargius-Saline Regional Natural Park, in Cagliari. It is part of a broader effort to regenerate abandoned and underutilised urban spaces, transforming them into areas that support biodiversity, promote sustainability, and engage the local community in environmental stewardship (3,4). The primary goal of the Bee Park Molentargius project is to restore specific areas of the Molentargius Park to their original ecological and productive functions. It aims to enhance biodiversity, support sustainable agricultural practices, and promote environmental education. The project includes the creation of shared gardens and an educational apiary, designed to reclaim the park’s identity and encourage local participation in the management and preservation of this important natural resource (1,3). It was developed with financial support from the Autonomous Region of Sardinia and the European Union's Horizon Europe Framework Programme. Inaugurated in March 2024, the project is a collaborative initiative involving local citizens, institutions, and park beneficiaries. It includes various educational components, such as beekeeping and olive growing training courses, along with sensory analysis workshops for honey and olive oil. These activities are intended to educate the public while fostering a sense of community ownership and responsibility toward the park​ (1,2). The project indirectly addresses environmental hazards related to the degradation of urban green spaces and loss of biodiversity. By restoring the park’s natural and productive functions, the Bee Park Molentargius helps mitigate risks associated with urbanisation, such as habitat loss and the decline of pollinator populations, which are crucial for maintaining ecological balance and food security​ (3)

The Urban Center of Good Initiatives (CUIB), a social enterprise launched by the NGO Mai Bine in 2013, is designed to drive social economies and support sustainable development in Iasi. The enterprise operates a bistro that promotes social consumption by supporting local producers, adhering to slow food principles through the use of local and seasonal ingredients, minimizing food waste, and encouraging sustainable transportation, among other eco-friendly activities (2 & 4).
In 2020, CUIB and Mai Bine joined the FoodE program, a European research and social project focused on local agri-food systems. Funded by the EU’s Horizon 2020 Framework Programme for Research and Innovation (2014-2020), the initiative empowered grassroots organizations through co-creation and collaboration among diverse stakeholders (5).
The FoodE project strengthened CUIB’s mission to provide low-carbon-impact food, promote ecological, ethical, and artisanal products, offer solidarity services such as free meals for the most vulnerable, engage in low-waste operations, provide education on mental and human ecology, and foster community through social and cultural events (1, p. 98). To further these goals, CUIB organized co-design workshops with 100 community members, focusing on achieving zero food miles, zero waste, and eliminating food waste (1, p. 99).
The program also led to improvements at the bistro, including the creation of a courtyard garden, a small terrace garden, along with a community garden (1, p. 100). These gardens supplied food to the bistro, and bio-waste was composted to fertilize the plots (1, p. 102). CUIB also hosted 17 outreach events as part of the initiative, including ecological workshops and the creation of a vegetable garden at a local kindergarten (3, p. 114 & 6).
Beyond its environmental work, CUIB provides free meals for 100 beneficiaries and organizes food donations for 400 vulnerable children and individuals (1, p. 103).

The "Ventanilla Wetlands" Regional Conservation Area (ACR) is an area of 275.45 hectares protected and administered by the Regional Management of Natural Resources and Environmental Management of the Regional Government of Callao (1, 2). It was established on December 20, 2006, by Supreme Decree No. 074-2006-AG, to conserve a representative sample of the coastal wetlands of the Subtropical Pacific Desert (2). With an ecosystem shaped by various hydrological and ecological processes, the "Ventanilla Wetlands" ACR is home to 126 bird species and 27 native plant species, making it an ideal area for ecotourism, recreational, educational, scientific, and cultural activities, thanks to its landscapes and biodiversity (2). However, the Ventanilla Wetlands face several challenges due to urban growth, water pollution, waste, traffic and plane overflights from the National Police and Navy, leading to a decline in bird populations due to noise exposure (5).
This area is fed by the hydrological system of the Chillón River, by surface waters from the Sedapal oxidation ponds, and by water seepage from nearby human settlements and populations adjacent to the wetland. The Ventanilla Wetlands are also influenced by the marine system, especially in the northwest zone. This gives the ACR area lagoon-like characteristics, meaning that its waters are slightly brackish despite being separated from the sea. The internal hydrological system supports the growth of species such as cattails, bulrushes, and reeds. In total, there are 27 native plant species, which serve the function of filtering and purifying the wetland's water. Additionally, the flora provides protection and food for various fauna species, particularly birds, with 126 species recorded, including resident and migratory birds from the Andes, local areas, and the Northern and Southern Hemispheres. Moreover, this protected natural area is home to five reptile species, including endemic species from Lima that are endangered (3).

Mapinguari National Park, located in the Amazon region of Brazil, is a protected area distinguished by its rich biodiversity and vast expanse of untouched tropical rainforest (2). It was officially created on June 5, 2008, by decree, covering an area of 1,776,914.18 hectares (2). The Chico Mendes Institute for Biodiversity Conservation (ICMBio) manages the park. It is linked to a management plan encompassing several nearby conservation units and their areas of influence (2, 3). Its main goal is to preserve the valuable natural ecosystems and scenic landscapes of the Purus-Madeira interfluvial region, which includes savanna enclaves (2, 3). The ecoregion where it is located has a high priority for botanical conservation due to parameters such as species richness and endemism (3). Additionally, the area presents great environmental heterogeneity, with several isolated and unique ecosystems, aspects that have been considered for fostering scientific research and public visitation, with programs for environmental education, recreation in contact with nature, and ecotourism (3). On March 8, 2013, an advisory council for the park was established to involve various stakeholders in decision-making and the effective conservation of the park (2), and in 2018 a Management Master Plan was established, seeking to develop an integrated approach for the protection and proper management of the region, especially considering the socio-environmental impacts of the construction of the BR-319 highway and the deforestation caused by fires, the expansion of soybean cultivation, land appropriation (7) and cattle ranching from the neighbouring state (3, 10). It was established as a Natural Park in 2008, but over the years it has undergone changes in land regulations, adding or decreasing its size as certain mining activities have been allowed in the buffer zone (2)