Enhanced protection and restoration of coastal and marine ecosystems

The Miraflores Bicentennial Park has been built on the Malecón de la Reserva and the Quebrada de Armendáriz. It was inaugurated in June 2022 as one of the created projects within the framework of the commemorations of the 200 years of Independence celebrations (1). It is considered a new green lung of Lima (2), as it has a green area of 30,400 square metres and stands on one of the cliffs of the Costa Verde (1). It has a system of terraces that replicates the construction model of the Incas, which has made it possible to additionally reinforce the soil and the slopes with the use of retaining walls up to 10 metres high, with horizontal geogrids and vertical geocells (1, 2). It was structured on a stabilised slope in order to mitigate the risk of landslides (4), and an irrigation system was implemented to stabilise the soil (4).
This space was built as a biodiversity garden with more than 160,000 xerophilic coastal species with low water consumption, 300 trees and 80 palm trees. It also offers places for tourism, such as viewpoints and squares, where cultural events, open-air activities and rest areas are held (1). It also aims to connect aspects of landscape conservation, preservation of biodiversity in the city, and the construction of a cultural landscape in which human action is complementary and friendly to the natural environment (9). Finally, it seeks to contribute to the reduction of the municipality's carbon footprint by reducing the harmful effects of urban expansion on the Lima cliff ecosystem, such as deforestation, water pollution and loss of biodiversity (9).

The Ciénaga de las Quintas is a coastal wetland located alongside one of Cartagena’s main roads, adjacent to the public market square and situated between the Jiménez and Bazurto Bridges. It is home to two predominant mangrove species (Ref 1). The wetland currently faces pollution problems because it is used for the disposal of solid waste, such as plastics and construction materials, and it receives wastewater and household garbage from nearby residences. Las Quintas is also the main waste disposal area for the Bazurto market, which handles 43,430 tons of food products each month (ref 3). The recovery initiatives for the Ciénaga de las Quintas are led by the Environmental Public Establishment of Cartagena (EPA Cartagena) in collaboration with other public institutions, the private sector, and citizens, with the main goal of achieving the ecological restoration of the city's water bodies and to maintain and preserve our mangrove ecosystems (ref 2). Since 2020, key implementation activities have included the removal of solid waste, planting of native tree species, dismantling of informal structures within the mangrove zone, and the rehabilitation of areas previously occupied by debris (Refs 4, 5).

The Parque Lineal de Crespo in Cartagena, Colombia, is an urban green space built in 2016-2017 that had fallen into neglect (ref 4) and recently has undergone revitalization initiatives (ref 2). Announced in January 2024 by the Mayor of Cartagena, Dumek Turbay Paz, the project aims to reclaim and enhance this public park as a hub for recreation and community activities, fostering urban well-being and environmental stewardship​ (ref 2 and 3). The local government spearheads the intervention, and the Instituto Distrital de Deporte y Recreación (IDER) has been tasked with the park's management, ensuring its upkeep and the development of activities. The project was launched following an inspection by the Mayor and other local officials, who underscored the need for better infrastructure, safety, lighting, and green coverage through tree planting ​(ref 2 and 3). The primary objectives of the Parque Lineal de Crespo project include revitalising the park through enhanced maintenance, security, and the introduction of recreational and sports facilities. The project also aims to relocate weekend recreational activities, such as a popular bike path (ciclovía), from the congested Avenida Santander to the park, thereby reducing traffic disruptions and enhancing safety ​(ref 2 and 3). The park is relevant for the city because it combats coastal erosion caused by the rising Caribbean waters (Ref 1). The Park aims to be an icon of culture and recreation (ref 1). The project inspired a neighbours initiative, the Friends of the Crespo Linear Park, are a non-profit organization whose objective is to collaborate in the conservation of the Park by contributing awareness initiatives to the population, alerting authorities, and developing new ways to interact with the environment, such as guided bird watching activities and sports (ref 1).

Brookley by the Bay is a 98-acre new waterfront park project along Mobile Bay's western shore (Ref 1). The park aims to reconnect people with the Mobile waterfront and coastal ecosystem (Ref 2). The area, once an abundant mosaic of tidal marshes, forested wetlands, and shallow lagoons, became a port, leading residents to lose contact with the natural landscape (Ref 2).
The park serves both recreational and environmental purposes, aiming to create and restore areas that enhance habitat resilience and allow coastal ecosystems to thrive (Ref 1). It features sports facilities, including kayaking, volleyball, golf, and biking, along with social gathering and educational spaces such as an amphitheatre lawn, a performance pavilion, and picnic tables (Ref 3, Images 1-3). The park provides safe and equitable access for all Mobile residents to nature, beaches, tree canopies, open fields, and varied shorelines, all connected by pedestrian and bike lanes (Ref 2). The project also focuses on habitat enhancement and restoration for biodiversity (Ref 3, Images 1 & 4), as well as flood protection through shoreline get-downs, vegetated edges (Image 4), and undulating berms and swales that serve as a layered protection system against stormwater and coastal flooding (Ref 2).
The development of Brookley by the Bay was guided by input from over 300 community members (Ref 1), local stakeholder organizations, and project partners, with the goal of establishing a more resilient, accessible, and enduring space for generations to come (Ref 2).

The Three Mile Creek Watershed project is part of the City Council watershed management plans (Ref 2) to stabilize the banks and the stream along the Twelve Mile Creek and Langan Park Lake, both of which drain into Three Mile Creek and Mobile Bay (Ref 1). The project aims to address the issues of degradation of the banks and destabilization of the creek, undercutting of sanitary sewer crossings and sedimentation in the creek and Langan Park Lake because of the increased water flow speed due to stormwater conveyance (Ref 2). Besides, major pollutants from run-off and sewage water contribute to the degradation of Three Mile Creek (Ref 5). Key initiatives include stabilizing the banks and streambed of the Twelve Mile Creek, dredging and restoring Langan Park Lake, and implementing instream structures to reduce erosion and protect infrastructure (Ref 2). The project also emphasizes reducing pollutants from stormwater runoff, improving water quality, and helping to protect the area’s estuarine and marine water resources (Ref 1). The project will increase natural habitat and contribute to regulating biodiversity by aiding in the abatement of invasive species such as the apple snail (Ref 2). It is expected to contribute to enhancing recreational access through the development of trails, educational programs, and water sports facilities. The overall goal is to restore ecological health, support flood control, improve the quality of life in the Mobile and Prichard communities and make the Three Mile Creek a recreational destination (Ref 6).

Cagliari's waterfront is currently characterized by extensive soil sealing, which has rendered the soil impermeable, leading to a loss of biodiversity and contributing to the urban heat island effect. Additionally, the waterfront is disconnected from the city due to heavy traffic. In 2023, the Municipality of Cagliari launched the "Green Promenade for Cagliari’s Seafront" project, aimed at revitalizing the waterfront and reconnecting the city with its coastal heritage. Led by Stefano Boeri Architetti, the project seeks to transform the area into a continuous green space that integrates pedestrian pathways with shaded public areas, functioning as a "green lung" to mitigate urban heat and enhance biodiversity.
The initiative will introduce over 200 new trees and 5,700 square meters of green space, creating a park that beautifies the area, improves air quality, and lowers local temperatures. A key focus of the project is fostering cultural and social inclusion by developing new community hubs that encourage diverse activities and strengthen social cohesion. Additional features include recreational areas, sports fields, and outdoor seating. (Ref. 1, 2,3)
The project also aims to enhance social inclusion, environmental sustainability, and urban connectivity, ultimately transforming the waterfront into a vibrant public space that reflects Cagliari’s identity.
However, the lengthy construction process has disrupted local businesses and reduced foot traffic, making the area less attractive during the redevelopment phase. (Refs. 10, 11, 12 & 13).

The Gårda pilot rain garden has been constructed as part of the research project Innovative Rain Gardens at Chalmers University of Technology in Gothenburg. In addition to causing flooding, runoff rain water in urban environments can be contaminated with microplastics, organic pollutants and metals which can spread into the natural environment. Yet, most of the storm water in urban environments is not treated. The purpose of the Innovative Rain Gardens project is to research the ability of a pilot rain garden to treat such pollution. The project acknowledges the function of a rain garden to prevent flooding, but in this study only the pollution treatment potential is investigated. The pilot rain garden was constructed next to the E6 highway in central Gothenburg [Ref. 1-4]. It includes several different bioretention filters where selected plants are grown in filters containing different materials such as biochar, ash and soil [Ref. 2, 3]. Results so far show that the use of rain gardens can significantly reduce pollution. However, further research is needed to determine the long term function of the bioretention filters and the potential of scaling up the NBS. The project is funded by the Swedish Research Council for Sustainable Development (Formas), IMMERSE - Implementing Measures for Sustainable Estuaries, an Interreg project supported by the North Sea Programme of the European Regional Development Fund of the European Union, and COWIfonden (private foundation) [Ref. 1-3].

The Martinican Marine Natural Park (MMNP) was established in 2018 to protect key marine habitats, including coral reefs, mangroves, seagrass beds, and open waters. These areas are home to important species like sea turtles, dolphins, and tropical fish. The park’s conservation efforts focus on addressing threats from human activities such as pollution and overfishing. It also collaborates with ocean-related industries, such as tourism and fishing, by recommending, funding, or conducting research aimed at promoting more sustainable practices within the MMNP.

To support its work, the park operates a growing fleet of boats that raise public awareness, resolve conflicts, and enforce the protection of designated areas. The MMNP spans an area of 47,340 km², extending from Martinique's coast to the boundary of the French Exclusive Economic Zone. The park's management board, which includes diverse stakeholders, must be consulted for advice on development activities that impact the marine environment. Their goal is to balance competing interests within the region.

The park receives funding from the French Office for Biodiversity (OBF) to carry out initiatives that protect the marine environment, promote sustainability, and raise public awareness. Notable efforts include creating or restoring habitats for species such as sea turtles and sea urchins, managing invasive species like sargassum algae, restoring coral reefs, and training resource users such as whale-watching companies and diving clubs. Other initiatives include reducing plastic pollution through clean-ups, supporting sustainable fishing practices (e.g., artisanal coastal fishing), installing eco-friendly moorings, funding Marine Educational Areas (MEAs), and sponsoring cultural events that promote marine conservation (Ref 1; 2; 3).

Del Nervi Park is a project co-led by the Port System Authority of the Sardinian Sea and the Municipality of Cagliari. Completed in 2021, it transformed a long-abandoned and degraded area on the Cagliari waterfront into a vibrant green space. The two-hectare site surrounds a 1950s industrial building and underwent extensive redevelopment to enhance its structural integrity and convert it into a public park. With a budget exceeding 5 million euros, the project prioritized green investments by creating new pedestrian and cycling paths, along with green spaces featuring local plants, flower beds, grass, and lawns.

Nervi Park is set to become a key destination for leisure, sports, and cultural activities, while also providing the Cagliari community with greater access to green spaces. The environmental and urban renewal efforts aimed to beautify and modernize the area, with future development plans focusing on long-term management and the introduction of commercial activities to further enhance the space
The project faced significant barriers, including prolonged disruptions due to the COVID-19 pandemic, which halted work for about eight months. (Refs. 1, 2, 3 & 4).

The Mobile Bay National Estuary Program is one of 28 National Estuary Programs established by the United States Environmental Protection Agency, focused on safeguarding and restoring the water quality and ecological health of nationally significant estuaries (Ref 2). One of the four main areas of work of the project (Ref 2) is focused on Ecosystem Restoration and Protection (ERP), aiming at restoring and protecting ecosystem function and services (Ref 4). One of the projects implemented in 2023-2024 in the ERP category is the Deer River Coastal Marsh Stabilization and Restoration project, aiming at restoring and protecting the saltwater marshes of the area (Ref 8).
The issues faced in the Deer River Shoreline are shoreline recession, marsh deterioration, and loss of natural function from erosion, apparently caused by heavy storms, tidal impacts, and wakes from cargo ships entering or exiting the Theodore Ship Channel (Ref 8). Indeed, the saltwater marshes of this area have started to erode at a rapid rate, up to 12 feet per year (Ref 7).
The project aims to enhance the natural function of ecosystem services to improve the area's resilience. It will restore the eroded marsh by creating offshore structures to protect the shoreline and attenuate the waves. The project also aims to restore the water quality of the Deer River by dredging it out, thus improving the water flow. The material dredged out will be used to nourish the marsh (Ref 9).