Sequester and store carbon

The area was planned to be the Öresund Region's most climate-smart city district: an energy efficient, resource-saving and green district with a hundred percent renewable energy use.” (ref. 2). The area's development program focused on the ecological aspect of sustainability and took responsibility for that part of the city's sustainability work (ref. 7).

The Urban Ecology Agency of Oslo (Bymiljøetaten) installed two CityTrees in the city of Oslo to act as green lungs in the city and reduce air pollution. The two CityTrees were placed at the Solli plass by Sommerrogata and on Nordraaks plass, close to Slottsparken. The CityTree is an environmentally-friendly plant wall with benches. (Ref. 2) It is an invention of a German company, Green City Solutions, and acts both as an aesthetically attractive furniture for resting, while simultaneously combating air pollution in city centres. (Ref. 1)

Revitalization of Rakova Jelša includes cleaning of the informal waste area and renovating it in a park which connects the city with the Marsh Landscape Park. In two phases, the park area was arranged together with the children's playground and the footbridge over Lahov graben. The possibility of regulated urban self-sufficient agriculture or gardens in the immediate vicinity of the city center means the added value of this area. (1)

FutureBuilt is a program running between 2010-2020, with expectations to continue from 2021-2030 (Ref. 9). One of its projects consists of the construction of a large greenhouse in between a housing complex in an old industrial building. The greenhouse will be the centre of the building and provide a Mediterranean climate with a lot of green facades, green roofs and indoor vertical greeneries (Ref. 1). The nave of the complex will become a greenhouse and the natural gathering point for the residents. (Ref. 1, 3)

This underground garage in Alicante, Spain, received a green roof makeover according to Alicante's climatological conditions (Ref. 2). Urbanarbolismo, a Spanish firm with a strong focus on vegetation, designed and installed this succulent garden in the courtyard of the garage. The garden is very low-maintenance and doesn't require any irrigation whatsoever. Further, with every passing year, it will grow more and more beautiful as the plants grow larger and take root. The Urbanarbolismo Benisaudet IVVSA parking garage was created by this Spanish design firm with the purpose of "keep[ing] the underground lot cooler, as well as improv[ing] its air quality." (Ref. 1)

With the "Green River" for Milan, the design team coordinated by Stefano Boeri has proposed an urban reforestation project that aims to realise on 90% of the seven abandoned railways a continuous system of parks, woods, oases, orchards and gardens for public use, linked between them by green corridors and bicycles made on the railroad tracks. (1, 3 and 4).

This is a project financed by the EU LIFE Project on CO2 sequestration and reduction levels in the urban area of Rome. One of the initiatives involved an NBS, as RomaNatura took care of planting new trees over 2 hectares of land in the Valle dei Casali in the Municipio XV area (Ref. 1).

The first " ecological zone" in Ljubljana was established in 2007 in the old city centre. This led to the closure of a 100,000 m² area to motor vehicles, and the renovation of the main traffic axis to make it attractive for pedestrians and cyclists. The new transport regime in this area reduced black carbon levels by 58%. Additionally, the city administration has planted 63 ash trees. Biking and sustainable mobility have been promoted, in line with providing new green areas for social and sporting activities in formerly degraded areas. The "renaissance“ is not focused only on the city center and the implementation of the car-free zone, but it is expanded throughout Ljubljana and covers different fields, such as the revival of degraded areas, the establishment of green public spaces, playgrounds for children, eco-renovation of schools and kindergartens, cultural and sports facilities, etc. Finally, the river Ljubljanica has been the focus of an ecological restoration project. This was done with the aim of reducing pollution and returning the city centre to the citizens, by incentivizing pedestrian and bicycle commute. The "ecological zone" project has been completed. After the completion of the project, further initiatives were taken which is directly related to the project itself. Some of them focusing on converting the city to a sustainable one is still going on. (1, 3, 4 and 8).

This is a pilot project part of the strategic plan "Città di Città" in the Milano province, launched in 2006 by the Direzione Centrale Risorse Ambientali, by the Parco Agricolo Sud Milano and by the Multiplicity.lab of the Politecnico di Milano. The project consists in the realisation of a green ring surrounding the city for an extension of 30.000 hectares (15% of the metropolitan area). The ring will connect a series of green areas already existing in the city. The project will insert a total of 3 million new trees along different areas of the city (2). The "metrobosco" is described as: a green belt made up of new forests, parks and rows that extend along the borders of the capital of Milan. A continuous ring of trees and small and large clearings to meet farms, abbeys, watercourses, agricultural areas and spaces for recreation and sports. The project arises from the need to redefine the relationship between city and country, to intensify plant and animal biodiversity, the preservation of existing and the construction of new "ecological corridors", the mitigation of climate imbalances, the abatement of noise and atmospheric pollution, the care and maintenance of the territory and the production of sources for agro-energies (4).

On a yearly basis, the city of Zagreb, Zagrebački holding plants new trees and bushes to maintain Zagreb as a green city with 114 hectares of green spaces (Ref 2). Also includes maintenance of green surfaces, such as grass in public parks along with tram tracks and planting new trees and maintaining existing ones next to kindergartens and schools (Ref 2). Maintenance of city parks, lawns and tree lines includes cleaning, mowing and collecting grass and garbage from green areas, restoration of trampled lawns, maintenance and pruning of trees, shrubs and hedges, maintenance and care of seasonal and permanent flower beds, maintenance of paved and dune areas in parks and installation and maintenance of urban equipment in parks and children's playgrounds (Ref 1).