Measurements of biophysical aspects of the NBS (e.g. temperature, water flow)

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)

The Ville Forests covering the hills between Bonn and Cologne are an example of a rare and highly endangered forest habitat type in Europe giving a home for many threatened animal species (1). The protection and conservation of these 'oak-hornbeam forests on hydromorphic soils and the forest-dwelling species was the main objective of the Villewälder: LIFE+ Project for Kottenforst and Ville project which includes four Natura 2000 areas with 4.378 hectares of forest. The conservation measures of the project focused on water balance restoration, habitat improvement and preservation, and the extension and connection of protected areas (1,2).

The aim of Ljubljanica Connects funded by Life+ is to improve connectivity between Natura 2000 sites. Started in 2012, the project aims to remove barriers to fish migration, enhance and restore habitats, improve water management infrastructures, and put in place a water monitoring system. This will restore the river Ljubljanica's function as a corridor, improve water management and so provide better links between Natura 2000 sites. The fish species in question are Danube Roach, Danube Salmon and Striped Chub (2).

This project focuses on the development of environmental regulations stimulating the connection of existing green areas and developing new ones in the urban area of Rome to stimulate biodiversity by rehabilitating 73% of free/derelict areas. This was done to guarantee an integrated protection of already existing areas as well as restoration of green and blue landscapes (1). The Ecologic Network is still ongoing and provides specific limitations to any new infrastructural project to make sure specific environmental standards are respected (3).

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).

The largest rain gardens in Sweden (thus far) has been created in Göteborg (Kviberg park). Kviberg's multisport arena was completed in the summer of 2015 in the northeastern part of Göteborg. Around the facility, there are parking spaces with a capacity for 500 cars. In order to handle the rainwater flowing from the parking area, approximately five per cent of the total area has been used for rain gardens, which both clean and store the rainwater. (Ref. 1, 2)

The Venice Lagoon is characterised by intensive agriculture and by a web of drainage channels discharging into the rivers. The Veneto Region, through the “Plan for diffuse pollution prevention and restoration of water in the draining basins of the Venice Lagoon” financed measures of re-calibration of riverbeds aimed at the renaturation of the hydraulic web, to increase the time of permanence of water and phytodepuration processes in the draining basin. This case study, in particular, includes measures on the drainage channels discharging into the Dese river, one of the main water bodies of the Venice Lagoon basin. In particular, it aimed at re-structuring the effluents of the mid-course of the Dese river (Rio S. Martino, Rio S. Ambrogio and Scolo Desolino). (1).

The project LIFE SeResto (LIFE12 NAT/IT/000331) aimed to trigger a process of aquatic recolonisation in “Northern Lagoon of Venice”, mainly through the transplantation of "Zostera marina" and "Zostera noltei" to small sites distributed throughout the area. The proposed intervention technique involved transplanting a small number of plants, with advantages in terms of lower costs and impact on the donor sites (1).

The ReLambro project is based on a metropolitan view where nature becomes an occasion for regeneration of the city: the river is no longer an empty and abandoned space but draws a great ecological and environmental system. The interventions, during the design phase, provide for the restoration of the naturalness of large sprawling areas, the reinforcement of the hedges and rows and channels system, the reorganisation of public and fruiting functions in areas at risk of flooding. The project strengthens ecological function by integrating it with urban functions (2).