Joint implementation (e.g. tree planting)

In 2010, rehabilitation works on the Huveaune riverbanks, in the city of Marseille, were carried out by volunteers from three associations: Rives & Cultures, Planète Sciences Méditerranée, and Hunamar. Work included clearing, revegetation, and maintenance of riverbanks (Ref. 1). Since this initiative took place, the l'Huveaune Watershed Union has been formed and taken steps to formalize the rehabilitation of the Huveaune riverbanks (Ref. 2, 3, and 4).

The Toulouse based project Green My City is a community collective focused on promoting sustainable consumption and creating a sustainable environment, (Ref. 2) It anticipates constructing thousands of square meters of organic vegetable gardens on the roofs of the city of Toulouse, saving 50 tons of CO2 emissions per year. The project defines itself as a prospective tool, which intervenes in the stream of gardening initiatives: it maps, selects, and then accompanies the initiatives (Ref. 1). The project supports the realisation of environmental initiatives by engaging citizens, communities, businesses and designers to help create an urban oasis (Ref. 23).

Together with the Office for Urban Greenery and Waters of the City of Leipzig, the charitable association Ökolöwe Leipzig started the green facades initiative "Kletterfix - Green Walls for Leipzig" in 2015. The project aims at creating awareness about the multiple benefits of urban green walls and inspiring action of tenants and landlords on private property. As a measure mandated by the Urban Clean Air Plan, green facades improve the urban microclimate, general living conditions and combat particulate matter pollution. On-site advice about suitable plants and maintenance is provided upon application and respective seeds for up to 5 plants are sent for free to the applicants by the city department (1, 3, 7).

The Pasteur clinic in Toulouse installed a 500m² vegetable garden on the roof of its building in 2014. Maintained by clinic employees and various associations, the garden makes it possible to develop a friendly atmosphere and learn gardening while promoting biodiversity (Ref. 2). The garden grows produce including green beans, tomatoes, basil, strawberries and raspberries, (Ref. 3) and contains flowers such as nasturtiums, Cosmos, tagettes and edible chrysanthemums (Ref. 4).

Arkwright Meadows Community (AMC) Garden is situated in the heart of inner city Nottingham, Prior to 2001, the site was a disused, derelict and rubbish-strewn piece of land. In 2001, a group of Meadows residents came together to improve this derelict piece of land and work started to create the infrastructure of the community garden. The area was transformed into a green oasis and outdoor learning environment. (ref. 8)

Citizen Farm was a start-up founded by Pierre Osswald (Ref. 3). The project began with an experimental urban farm in a vegetable garden of Raymond 6. The ozarium farm (a vegetable aquarium) uses a technique called aquaponia (Ref. 5). This technique grows all kinds of plants and vegetables indoors in an entirely natural way. Fertilizer or watering are not needed. Plants feed on the nutrients in the aquarium: water and fish discharges. In return, they purify and oxygenate fish water. It is an ecological and educational innovation which is surfacing as an "eco-responsible" trend. (Ref. 1, 2). The Citizen farm initative was ended in 2018 due to financial difficulties (Ref. 35).

The ANNALINDE gGmbH operates multifunctional urban agriculture and demonstration projects in the Western part of Leipzig: a community garden, a nursery and a fruit garden on a former train station where the emphasis is on community development and mutual learning processes in addition to food production. This is safeguarded by an events portfolio consisting of garden working days, workshops and collaborations with schools, kindergartens and like-minded organizations. In addition to that, open urban labs are operated for a number of initiatives and projects covering subject areas like urban agriculture, recycling, composting, urban bees, urban resilience and sustainable urban development (1).

This NBS refers to a curtain protection forest that was planted 6 km out of the city of Iasi in 2015 by the mayor of a commune next to the city. The benefits of this NBS embrace also the city of Iasi as a method to prevent flooding and to avoid strong winds in the area. Afforestation was seen also as a response to the existence of arid soil and abandoned crop fields in the area due to a large population movement of immigration towards Western countries (1)

After being abandoned for more than 10 years following the collapse of a building, a piece of land inside the city's "Le Panier" district was approved by the city in 2017 to become a "neighborhood garden" combining green space and a community vegetable garden (Ref. 1). After many delays the project was completed in early 2020 and the garden opened on February 28, 2020 (Ref. 11). The district "Le Panier" (where this intervention occurs) attracts many tourists every year for the charm of its narrow streets and colorful facades (Ref. 1).

The project is the reforestation of the peri-urban parks of the city of Malaga in order to make the city greener while adhering to the dry and hot climactic condition of the region. It consists of phases, where native trees to the region were planted totaling over 50 000 new trees in the city. (ref 1-10)