Expected reduced biodiversity loss

The City of Marseille is engaged in a city-wide project to develop community gardens across its territory. It supports project leaders by providing municipal land and offering a framework along with technical support (Ref 5). Currently, there are 80 community gardens, including 66 shared gardens and 14 family gardens, covering nearly 32 hectares in total (Ref 1).
Marseille aims to provide all residents with spaces for relaxation and socialization in every neighbourhood, particularly fostering shared gardening spaces in neglected land, forgotten squares, building bases, or areas awaiting development. (Ref 1). Community gardens contribute to the city's beautification and support biodiversity (Ref 1) and are founded on values of solidarity, conviviality, and fostering connections between generations and cultures (Ref 4). This initiative also addresses the issue of agricultural land disappearing due to urbanization, while Marseille's many abandoned wastelands offer genuine opportunities to rethink production models (Ref 3).
The city has created a Charter to be signed between the city and garden managers, which can include groups of residents or associations (Ref 2). The charter includes criteria such as citizen involvement, fostering social connections, promoting biodiversity, restoring soils’ health, planting local species, and eco-responsible gardening practices (Ref 2). In return, the city supports the development of these gardens, providing land and offering technical and methodological assistance, including soil analysis and advice on environmentally friendly gardening practices (Ref 2). Additionally, community gardens can serve an economic purpose by creating jobs and enabling the production of healthy and flavorful fruits and vegetables at a lower cost (Ref 2).

Two stages of a project called "Flowering roadsides" have been created along a bike road stretch measuring 6,5 km between the areas of Gunnilse and Bergum in the eastern part of the City of Gothenburg. The projects came to be through citizens' initiatives and are carried out in cooperation between the City of Gothenburg and two local NGOs: The Bergum-Gunnilse Development Association and the Gothenburg branch of the Swedish Society for Nature Conservation (Gunnilse-Bergum utveckling & Göteborgs naturskyddsförening). The first stage of the project was carried out in 2021 and focused on taking inventory of species and ecosystems along the stretch and suggesting management options to promote biodiversity. The second stage is carried out from 2022 to 2024 and focuses on implementing and evaluating alternative management options to today's conventional management. Mowing and scraping are carried out to disturb weeds and benefit meadow flowers. Sand has been placed to create a habitat for wild bees. Signs were put up along the stretch to inform the public of the initiative, and benches will be renovated to create opportunities for recreation. The project receives funding from the Swedish Environmental Protection Agency through their local nature conservation investment, LONA. The project falls under the umbrella project of "the world's longest meadow", organised nationally by the Swedish Society for Nature Conservation [Ref. 1, 3, 4]. The goal of that project is to transform 1000 km of Swedish roadsides into flowering meadows with high biodiversity richness [Ref. 2].

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 regreening project is located in Seestadt Aspern, a newly developed urban area in Vienna's Donaustadt district. Two years after the completion of buildings, streets, and squares, the ground was reopened in 2022 to address the challenges posed by urban heat islands. Pavement was removed, and trees and shrubs were planted to provide shade, create insect habitats, and open seepage areas for rainwater. Additional features like benches, a water station, and water jets were installed to enhance the area's livability. These measures improve the overall quality of life, offering residents green spaces to relax and opportunities to cool down through water play.
The project spans three connecting squares in Seestadt: Wangari Maathai Square, Simone de Beauvoir Square, and Eva Maria Mazzucco Square. In 2022, Wangari-Maathai-Platz and Simone-de-Beauvoir-Platz underwent intensive regreening. By 2023, Eva-Maria-Mazzucco-Platz in the Seeparkquartier was similarly transformed with additional greenery and cooling features. Under the slogan "Out of the Asphalt," one of Europe's largest and most innovative urban development projects took a significant step toward improving quality of life.
In 2023, over 1,100 square meters of asphalt were removed and greened. This effort included the creation of 12 new green beds planted with grasses, perennials, and shrubs. The design also introduced two square-like recreation areas with existing seating elements surrounded by green beds, providing shaded, pleasant spaces for relaxation.
The Eva-Maria-Mazzucco square was designed by a local NGO specializing in citizen engagement in urban development, while the project's overall initiation and implementation were led by the City of Vienna, the Donaustadt district, and Wien 3420 Aspern Development AG. This collaborative effort demonstrates how regreening initiatives can mitigate heat islands, foster urban biodiversity, and create more attractive, livable spaces. (Ref. 1-3)

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 aims to protect seagrass meadows, which are vital habitats for the prey of resident dolphins and essential to the local fishing economy. The initiative involves local fisherwomen, called "Keepers of the Sea," in activities such as marine education, awareness campaigns, and monitoring the health of the seagrass meadows (Ref 1). Founded in 2015, Ocean Alive aligns with several UN Sustainable Development Goals, including ocean conservation, gender equality, quality education, and climate action (Ref 4). The project is supported by partnerships with UNESCO and other organizations, and it extends its efforts to Portuguese-speaking African countries. Ocean Alive’s activities also include advocacy for blue carbon ecosystems and programs that involve community engagement and social innovation (Ref 2, Ref 5).
One of several implementation projects targeted safeguarding the young seagrass meadow at Cambalhão Bay, at the entrance of the Sado estuary, as an Ocean Alive’s initiative in partnership with SeaTrees by Sustainable Surf (Ref. 2). The Cambalhão meadow is made up of 202 patches of seagrass. Unregulated shipping is one of the factors in the degradation of the prairie, and to protect it, Ocean Alive is running a campaign to raise awareness about recreational boating (Ref. 6).

North Bull Island is a national nature reserve located in Dublin Bay on the north side of Dublin. Supporting both local and migratory wildlife, the area holds several nature conservation designations. It is designated as a special amenity area for its aesthetic and recreational value and forms an integral part of the Dublin Bay Biosphere. The Island, with its 5 km beach located within the capital city and close to the city center, serves as a unique and important public amenity. (1)
The Island is estimated to attract up to 1.4 million visitors annually, including walkers, swimmers, beachgoers, birdwatchers, nature enthusiasts, kite-surfers, and various other interest groups from the local area. Additionally, it is a popular destination for schools, universities, and visitors from Ireland and abroad who come to experience accessible examples of ecological succession across nationally and internationally significant habitats, and to learn about the intricate stories that make North Bull Island Nature Reserve central to a UNESCO Biosphere Reserve and part of a global network of Biosphere Reserves. (1)
The Island and Nature Reserve are managed by the Parks, Biodiversity, and Landscape Services of Dublin City Council in collaboration with the National Parks and Wildlife Service. Dublin City Council has prepared an Action Plan for North Bull Island for 2020-2025 to implement the objectives of the North Bull Island Management Plan 2020. The North Bull Island Oversight Forum, which represents a range of stakeholders, monitors the action plan’s implementation (2). The goal is to conserve the island's environmental qualities and scientific significance while balancing its recreational and amenity value for the benefit of the local community and visitors (8).

Välen is a natural area 8 km south of central Gothenburg, established as a protected nature reserve in 2013. Prior to the establishment of the nature reserve, Välen was an agricultural area that experienced environmental degradation due to pollution from a nearby sewage treatment plant. Västra Frölunda Nature Conservation Association leased the land in 1985 in order to allow cattle to graze through the overgrown meadows as a form of landscaping approach [Ref. 5].
The City of Gothenburg took the initiative to protect and manage the area as a protected reserve [Ref. 1, 2]. It is formed of wet meadows and deciduous forests and has a total area of about 68 hectares, of which 52 ha are land and 16 ha are water. Välen is situated by the sea and the mouth of a small river, and protects some of the coastal waters. Residential areas surround the nature reserve and are a popular destination for recreation [Ref. 1-3]. In creating the nature reserve, efforts were made to make the area more accessible to visit and to provide learning opportunities. New paths, entrances and signs were established [Ref. 3-4]. The nature reserve is described as contributing to several national environmental goals, particularly goals related to biodiversity [Ref. 2].

Corkagh Park, spanning 120 hectares, holds significant historical and cultural value for the local community of Clondalkin. The park offers an extensive range of facilities, including football pitches, a newly redeveloped playground, baseball pitches, cricket amenities, and a purpose-built road cycling track. Over the past two years, Corkagh Park has experienced a notable increase in footfall and usage as visitors are drawn to its expansive open spaces. With its rich vegetation, open wetlands, and rolling hills, Corkagh Park provides a unique environment that caters to both wildlife and human visitors. Since its establishment as a public park in 1986, the park’s vast open spaces have served the local community and attracted visitors from the broader region. Currently, Corkagh Park is surrounded by the Village of Clondalkin and nearby residential developments.
Currently the park goes through a redevelopment process that involves redesign of several areas including introduction of native vegetation. The enhancement of the park is led by the South Dublin County Council and will feature a central hub area at the heart of the park. This hub will feature a coffee shop, an event space, additional seating, and new play areas. Enhancements to the Fairy Woodland Trail will include additional play elements and seating, as well as a new pedestrian pathway linking the lakes, while maintaining and safeguarding the existing mature trees. The project also includes the felling of ash trees affected by Ash Dieback, with these trees being replaced by native specimens to sustain the park’s ecological integrity. Native edge planting buffers will be established to reduce noise from the N7 and promote local biodiversity. Additionally, the project will address the existing car parks by implementing necessary improvements to better accommodate the park’s visitors. (4, 6)

The Dog River Watershed Restoration project aims to protect and enhance the chemical, biological, and cultural integrity of the Dog River Watershed in Mobile County, Alabama (Ref 1). Guided by the Dog River Watershed Management Plan (WMP), the project addresses key issues such as pollution, litter, stormwater management, and habitat degradation (Ref 2). Funded by the National Fish and Wildlife Foundation's Gulf Environmental Benefit Fund and completed in partnership with stakeholders, the project focuses on implementing targeted restoration activities to improve water quality, protect critical habitats, and increase public awareness and access to the watershed (Ref 2). The Dog River Watershed faces significant hazards, including pollution, sedimentation, erosion, and the impacts of urban development (Ref 3). These challenges are intensified by the watershed’s role as an urban estuary, where land use heavily influences water quality and habitat conditions (Ref 3). To mitigate these threats, the project incorporates pollution prevention measures, shoreline restoration efforts, and community engagement initiatives (Ref 4). By prioritizing scientifically supported actions and aligning with broader environmental goals, the project seeks to restore ecological balance and ensure the long-term health and resilience of the watershed and its connected ecosystems in Mobile Bay (Ref 4).
The Watershed Management Plan for the Dog River Watershed is a key component of the Mobile Bay Shore Habitat Conservation and Acquisition Initiative, which focuses on acquiring, restoring, and preserving habitats and wildlife species affected by the environmental disasters of the Deepwater Horizon oil spill that occurred in 2010 (Ref 6). The project spans three critical areas: 300 acres in the Dog River Watershed (as detailed in this project profile), 450 acres within the Three Mile Creek Watershed, and 40 acres in the Garrows Bend Watershed (not in focus here) (Ref 7).