Green roof research at the University of Münster
The aim of ReWaM was to show ways how different forms of use of water bodies can be reconciled with their protection in order to sustainably maintain the diversity and efficiency of the different water ecosystems. This applies to both rural, suburban and urban regions (ref. 8). Increased sealing of urban surfaces and combined sewer systems for rain- and wastewater pose major challenges for urban water management. Therefore, the university of applied sciences and the city of Münster participated in a research project as one of three pilot cities running from 2015 to 2018 concerning improved rainwater management and the development of respective planning instruments. Several green roofs at the university campus were used as test spaces to explore and monitor rainwater infiltration efficiency and feasible green roof compositions. Also, different permeable surface coatings were tested at the urban depot (Ref. 1 and 4).
Planting 3000 trees in park Zapaden by volunteers
3000 trees were planted on 7 decares of land by 500 volunteers in park Zapaden on Earth day (22 April) in 2017. The initiative was supported by the Municipality of Sofia, and had the aim of making the city cleaner, greener, and more beautiful. The initiative also compensated for the illegal logging which had taken place in the park. (Ref. 1; Ref. 2; Ref. 3)
Initiative City Forest
Sofia is Europe's most polluted capital and the World Health Organization alarmed that Bulgaria ranks second in the world in terms of deaths due to air pollution per capita. In response to that, the coalition Sofia - Green Capital planned to buy neglected urban land and plant an Urban Forest in order to restore the green passes that lead the fresh air from the mountain to the city. The Urban Forest is expected to improve the air quality, sequestrate carbon emissions, and also provide a place for walks and play. (Ref. 1; Ref. 2). The planting process started in 2018 and around nearly 60,000 saplings were planted over 225 acres by over 6,500 volunteers and over 50 companies joined in. (Ref 7, 8)
Community Garden Les Hauts sement
The community garden "Les Hauts Sèment" is located in Rouen in the district of Lombardy, being the first community garden of Rouen animated by the city in 2011. It is "an educational garden which has been created and is maintained by the gardener in association with users wishing to invest in the association. It is supported by different animations" (Ref. 1 and 2, page 12).
Blossoms Day Nursery Garden
The 'Painting the Town Green' project got to work with Blossoms Day Nursery, based at Wayfield Primary School. Working with parents of the two-year-olds who attend the nursery, they added more wildlife-friendly areas to the outdoor play space. The grounds are now home to colorful planters hung on the low fences, filled with bulbs which will flower in the Spring, and topped with miniature firs and winter pansies; a beehive-shaped compost bin. All of these things provide rich wildlife habitats and educational opportunities (Ref 1, 4).
Eco-Campus Community Gardens
The project is an initiative that is part of the environmental management system of the University of Murcia. This initiative aims to implement activities related to sustainable agricultural systems while also serving as a space for social cohesion for the members of the community (Ref 3). For this reason, a community garden was constructed and the slots are until 2019 distributed between members of the community of the university based on a bid (Ref 1).
Urban gardens of Poblenou
It is a community garden initiated by the autonomous assembly of the Poblenou neighborhood. It has changed location a number of times, eventually occupying the empty lot of demolished buildings. Over time the garden has expanded, taking over an adjacent empty space, as well as other yards in the neighborhood. The garden is not maintained for strictly productivity purposes, especially because much of its soil has been contaminated by a soap factory. It is, rather, used as a space for social encounter and knowledge sharing on planting and working with the earth on a communitarian basis (Ref 1 and description provided by CEU). This NBS is also part of a wider movement, the 15M movement in Spain (Ref 1), which had influence on the creation of larger similar global economic 'occupy' movements (Ref 5). Video for the opening party of the 8th self-managed squatted garden in the Poblenou neighborhood, Barcelona from April 11, 2020 shows that the idea of the first garden has lead to the creation of at least 8 of these gardens in the city (Ref 6).
Social urban gardens of “Pla Buits” (Vacant Lots Plan)
This is a co-management initiative fostered by the City Council of Barcelona that aims to involve civil society in defining, installing and managing unused spaces across all districts of the city. The city council provides temporary use for public entities or non-profit associations to develop temporary uses and activities (from one year to three renewable years) in order to promote social activism and cohesion in the neighborhood. Most part of activities are social urban gardens (Ref 1). The initiative had 2 editions, with 12 projects in the first one (2013) and 5 projects in the second one (2015) (Ref. 12). One of the most popular projects is the community gardens such as ConnectHort, in Poblenou, dedicated to permaculture, which has allowed the restoration of an abandoned area through sustainable urban agriculture practices (Ref. 12). Another project, the Illa dels Tres Horts project in the Font de la Guatlla neighborhood, is an orchard where work is done with vulnerable groups and allow the recovery of vulnerable species (Ref. 12)
Urban Green Corridor
The Barcelona Green Infrastructure and Biodiversity Plan 2020 includes the development of several urban green corridors to increase ecological and social connectivity within the city. The green corridor of Passeig de Sant Joan is one of the first of these corridors implemented. The project consisted of the renovation of the promenade through tree and shrub planting and permeable green pavement installation, creating a green boulevard that benefits pedestrians and extend the urban green spaces, which gave new life to the neighborhood and allowed the expansion of small businesses and tourism (Ref 1).
Community Garden Mariahof
Mariahof is a community garden in which a large variety of actors is involved including citizens, schools and an NGO that supports social inclusion. In the garden, vegetables are grown for non-commercial food production, organic waste is composted and bees are kept for pollination and honey production (1,2,3,6). The garden works to raise awareness about sustainability and nature stewardship in an urban setting (2).

