Private sector/corporate actor/company

The first external green wall in the public space in Poland was installed on the surface of a 30 square meters wall of the Infobox building in Gdynia [1,2]. The project serves aesthetic purposes and aims to improve air quality. The wall was composed of the plants suitable for the Polish climate conditions [3].

This pilot project to create social gardens in Gdynia was developed by a cooperative of the local government, NGO sector and businesses. The project involved creating 3 (and finally 6) social gardens in different locations of Gdynia (Oksywie, Grabówek and Redłowo). They serve ecologic (greenery planting), horticultural (jointly managed vegetable and herb gardens), social (community integration) and educational (workshops on topics such as healthy lifestyle or building bird boxes) purposes. The gardens are being co-managed on a voluntary basis by the local communities with the help of an appointed gardener and an animator [1,4]. The project is based on 4 pillars: 1) social participation; 2) innovation; 3) social sensitivity; 4) food anthropology [5].

Paljassaare peninsula hosts the Paljassaare special conservation area and is partly a nature reserve and partly used to accommodate a wastewater treatment facility (ref 3). The leftovers from the treatment facility, processes of urbanisation and cyanobacteria blooms from the Baltic sea are largely influencing the fragile ecosystem of the peninsula through eutrophication. By this, the different cycles and ecosystems (both natural and urban) got more and more intertwined. ‘Perpetuum Mobile’ project aims to rebalance the urban metabolism of Tallinn city with the ecological processes on the Paljassaare peninsula through natural de-eutrophication of the area (ref 4).

In 2017, under a bigger project, the municipality of Sintra started the work for the rehabilitation of an area that included beaches and rivers, such as the Mata river. The NBS solves a problem of accumulation of water and sludge that was unsolved, through the recovery and cleaning of Ribeira da Mata (small river/brook), planting trees and promotion of an improvement in water quality and sand on the beach.
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The main problem of Lake Ülemiste is high phytoplankton biomass, which increases the cost of water treatment (ref 1). Improving the water quality of Lake Ülemiste by biomanipulation has been considered as a management alternative. Lake Ülemiste was bio-remediated after reduction of external loading and the shifts in water quality were studied during the active-phase of the measure. (ref 1). Tallinn obtains 88% of the water it needs from Lake Ülemiste. Pine forest in the sanitary protection zone surrounding Lake Ülemiste offers several ecosystem services that help to improve the quality of the city’s drinking water (ref 4).

The abandoned fishing harbour in Tallinn is a derelict, privately owned but publicly used open space approximately 5 hectares in size and known as the former fishing harbour (Kalasadam). It is part of the old industrial waterfront belt waiting to be regenerated in the future. It is a piece of ‘urban wilderness’ (Ref. 1). The site is a green open space with high recreational values. Inserting a few pieces of equipment and taming the urban wilderness very slightly seems to lead to a significantly increased number of users than before these developments (Ref 2).
A research study has been done to determine whether an urban derelict site could be regarded as only empty and meaningless (ref 1 and 2)

This project aimed at the reconstruction of the Lepiku channel that is part of the drainage system, which starts next to the Tallinn Botanic Garden and includes wetlands, detention ponds, ditches and channels and flows into the Pirita river. The aim of the project was to improve the quality of the stormwater that flows into the Pirita river which is a Natura 2000 site and flows into the Baltic Sea. The work included: widening of channel bottom in different segments, creating artificial dykes and rapids and creating suitable conditions for the aquatic plants exhibited in Botanic Garden (ref 1). With the project, 200m of the channel was reconstructed (ref. 5).

The Danube Eco-District project is Strasbourg's first eco-districy and is based on previous experimental designs in sustainable urban living (Ref. 27, 30). It is situated at the heart of the axis Deux Rives, and is thus a strategic point of the large Franco-German Deux Rives project (Ref. 28). The district will have the capacity for 20,000 residents, and will include green spaces, green roofs, insect hotels (Ref. 1), various water management facilities (ditches, swales... etc.), and composting facilities (Ref. 4). The project aims to improve biodiversity, social equality, ecology, reduce urban heating, and promote sustainable consumption (Ref. 30).

The idea of ​​the project Redevelopment Of Place d'Austerlitz was to create an autonomous ecosystem, including plants and animals, with wild grasses and native trees that attract insects, mammals and birds (Ref. 4). The restructuring involved a whole mixture of paths, fauna, flora and riverside, all within a framework promoting urban ecology and biodiversity (Ref. 5). The project was conceived as "an archipelago of nature in the city" (Ref. 10, 12).

The Development Of The Banks Of The Faux Rempart Ditch is focused on the biological and ecological continuity of the right bank of the Faux Rampart (Ref. 6). The ditch was abandoned, underdeveloped and found to be lacking of the rich biodiversity otherwise seen in the surrounding area. thus, at the request of the local inhabitants, the City of Strasbourg intervened to revitalise the accessibility and greenery located at the area (Ref. 4).