Urban or built environment

The Tirana Vertical Forest is part of the city's 2030 Master Plan and aims to enhance urban biodiversity and create green spaces through innovative urban design (Ref. 1,2). The project was developed by Stefano Boeri Architetti, the same studio that has designed similar, well-known structures in cities like Milan, Utrecht and Nanjing (Ref. 6). The completion of the 21-floor building is expected in late 2024 and will feature 105 apartments and a commercial ground floor as well as 145 trees and over 3,200 shrubs and bushes which are integrated into the balconies and façade of the project (Ref. 1,2,3). Various Mediterranean plants have been incorporated, including colourful, scented and aromatic types, which harmonize with the local ecosystem. To maximise the space available for green features, a dynamic structure with alternating balconies and full-height windows has been built (Ref. 1,2). Ultimately, the project anticipates improving air quality, reducing noise, and providing insulation. The greenery is expected to capture fine particulate matter and up to 8 tones of Co2 per year while also creating a healthier microclimate for those inside the building (Ref. 1,6).

The "EnRútate por el Ambiente" initiative is a collaborative strategy implemented in Cartagena through a partnership between Ecopetrol, EPA Cartagena, and the Cartagena Refinery. The initiative aims to promote sustainable community development in neighborhoods adjacent to the refinery by addressing key environmental challenges such as pollution and the degradation of water bodies and green spaces. Its overarching objective is to improve quality of life through the promotion of sustainable practices and environmental stewardship (ref 5).
The strategy is structured around three programs. The first component focuses on the management of public spaces for recreation and environmental care. The second, Guardians of the Channels, seeks to empower local residents as promoters of water body conservation within their communities. The third program promotes the engagement of all community members, including schools and educational institutions, through participatory environmental initiatives (ref 1).

Miskolctapolca is a district of Miskolc and features a nature park (which includes a lake, Csonakazo-to) originally planted in the 1920s using the exotic trees and bushes. In 2022 the municipality decided to renovate the area under a EU funded project called "Creating a Green City in Miskolc-Tapolca". The project aimed to establish a modern urban green space focused on active recreation for various age groups, enhancing Miskolc's appeal for tourism.
The renovation included new concrete paving system and updated utilities for the lakes' promenades with a strong emphasis on accessibility ensured smooth mobility throughout the area. The renovation added informative signs detailing local attractions, historical trees, and the park's history. To enhance visitor comfort, a new accessible restroom was constructed. Renovations to the Csonakazo-to lake included removing accumulated silt and reinforcing the shoreline, alongside the addition of new street furniture, lighting, and wooden sunbathing terraces and platforms. The two bridges around the lake were renewed, and the squirrel installation, a favorite among locals, were restored. Furthermore, a square in the park, Kilátó Square was transformed with benches and drinking fountains, creating a welcoming space for relaxation.
Additionally, extensive landscaping was carried out, including the planting of approximately 100 trees, 9,000 shrubs, 18,000 perennial plants, 2,300 annuals, 350 roses, and 6,600 bulbs.
The surrounding park, which had been in disrepair for decades, was thoroughly revitalized, blending traditional and modern aesthetics. This long-overdue renovation significantly enhanced the environment. The construction was carried out by FEDRID Építőipari Kft., starting in spring 2022, and was completed in May 2023 after some delays.
(Ref.1,2,3)

The project to revitalize the Huveaune River and its biodiversity is taking place in Aubagne, a city within the Marseille Metropolitan area. For a long time, the river received little attention, constrained by urbanization, and was even covered for several hundred meters. Urbanization and the construction of a road have made the floodplain more susceptible to flooding (Ref 2). The initiative aims not only to restore the Huveaune and its environment but also to strengthen the connection between residents and the river (Ref 1) while reducing flood risk as a critical objective (Ref 1).
The challenge is transforming the area into a higher-quality environmental space with resilient ecosystems. A diagnostic conducted during the project's design phase revealed the site's degraded state, including the presence of invasive species, steep banks unsuitable for riparian vegetation, poor waterway conservation, and disrupted ecological continuity (Ref 2).
Key actions include revitalizing the river and its biodiversity, removing artificial banks, and creating new meanders to give the river a more natural shape. Diversifying flow patterns will create habitats for aquatic and fish species by varying water heights and flow speeds. This involves increasing the river's sinuosity and varying the width of the minor riverbed (Ref 2). Additional steps include planting trees and shrubs adapted to the Mediterranean climate with low water needs (Ref 2). To bring residents closer to the river, plans include creating walking and cycling routes, sports equipment, educational panels, and useful visitor facilities such as benches, water points, and restrooms (Ref 3).

The Urban Oasis Playgrounds project focuses on creating a guide for green regeneration of playgrounds located all over Iasi by using natural climate solutions, with the potential for wider application beyond the city(1 to 6). The project's primary goal is to tackle pollution in playgrounds and address the overall lack of green spaces for children (1). This initiative is led by the NGO Civica in collaboration with the Municipality of Iași and the Architects Association in Iași (OAR) (1). The project secured €50,000 in funding after winning a competition organized by Raiffeisen Comunități, with support from the NGO "Asociația pentru Relații Comunitare" (2 & 3).
In addition to pollution, the project seeks to address other critical issues, such as the heat island effect and the proximity of playgrounds to risk-prone areas (1). The guide will be developed based on public consultations with Iași residents and a comprehensive study to tackle these concerns (1 to 7).
Currently, the first phase of the project is underway, involving assessments of various factors in playgrounds, including existing vegetation, shading, surface quality, infrastructure conditions, and pollution risks (4). These aspects are also reflected in a questionnaire distributed to the public, which gathers opinions on factors like cleanliness, noise exposure, thermal comfort, safety, and preferred natural green solutions (6).
The initiative aims to raise awareness about climate change, actively engaging the community in the process (4). Once completed, the guide will be presented to the municipality with the goal of being adopted as a standard for future playground developments (1, 3, 4, 6). The first phase of the project will regenerate a playground by planting trees and native vegetation (3).

The redesign of Reinprechtsdorfer Street in Vienna is a greening initiative aimed at climate adaptation by reducing local temperatures and increasing green space in a densely built urban area. Implemented within one year, the project included planting trees, adding green beds, and widening the pavement to create a more inviting environment. New seating areas, drinking stations, and water play installations were introduced, providing spaces for relaxation, cooling off during high temperatures, and fostering social interaction. Accessibility and traffic safety were enhanced by leveling the pavement with the street and adopting a one-way system for cars.
The project, realized in 2023, was part of Vienna's city-wide "Out of the Tarmac" initiative and was spearheaded by the district and city council. It originated from discussions and a participatory design process with citizens dating back to 2014. Previously, Reinprechtsdorfer Street served as a congested connection between Wienzeile and Gürtel. The plan seeks to transform it into a “climate-friendly shopping street.”
The redesign involves planting 32 new trees accompanied by flower beds, plus three standalone flower beds. Sidewalks were widened, and amenities included parking for 36 bicycles, nine benches, and seating for 46 individuals. Cooling features such as two water installations, three mist columns, and two drinking hydrants will enhance comfort.
Renovation began in spring 2023, focusing first on the 400-meter stretch between Schönbrunner Straße and Arbeitergasse. A structurally separate one-way cycle path will link Schönbrunner Straße to Bräuhausgasse, while the existing cycle lane against the one-way system remained unchanged. (Ref. 1, 2, 6)

The City of Seville has carried out four tree planting campaigns between 2020 and 2024, aiming to meet the goals of its Urban Tree Management Plan for Seville [Ref. 2-7]. The intervention as described here is based on the planting campaigns to date, but as the Management Plan spans from 2019 to 2039, more campaigns can expected in the future. The tree management plan aims to provide guidelines for the planning of trees in the city to maximise their value and minimize conflicts. As part of the process, the current state of the tree population in Seville has been evaluated. The management plan describes the ecosystem services of trees related to climate adaptation, biodiversity and public health. It also identifies challenges and conflicts that may arise due to urban trees and their management [Ref. 1]. The plan has a goal to increase the tree cover in Seville by 5 % over 20 years, which leads to the ambition of planting 5000 trees yearly and the tree planting campaigns over the last years. Between 2020 and 2024, about 1000-5000 trees have been planted each year [Ref. 1-5].

This initiative is a community-based urban greening effort targeting environmental and social co-benefits in Cartagena’s El Pozón neighbourhood. It involved the planting of 491 fruit and timber trees along a 1,500-meter linear stretch, covering nearly two hectares in the Terraplén sector of the neighbourhood. Led by the "Establecimiento Público Ambiental" (EPA), it was developed in collaboration with various stakeholders, including the Gerencia de Espacio Público, Guardia Ambiental, SENA students, the Police, and community members (ref 1, 2). The project's primary goal was to enhance the environmental quality and aesthetics of the El Pozón neighbourhood by planting trees that provide ecological benefits, such as improving air quality, reducing temperatures, and enhancing biodiversity. Additionally, the initiative aimed to foster community engagement in environmental conservation, particularly in raising awareness about the importance of protecting and maintaining nature. The community is also expected to take on the responsibility of maintaining the planted trees, promoting a sense of ownership and sustainable stewardship (ref 1).

The Adana Central Park stretches along both riverbanks of the Seyhan River. The idea was first introduced by the former mayor of the city, Aytaç Durak, in the late 80s to address the need for accessible green spaces in the developing area (Ref, 2). Previously, citrus gardens and informal settlements were located on these riverbanks, which now host over 400.000 plants and 67 different tree species on an area of 33 ha (Ref. 2,5,6). In 1998 construction of the park began, which lasted until 2004 (Ref. 2,5). The park is appreciated by visitors for its aesthetically landscaped appearance and the many amenities for children, youth, relaxation and socializing (Ref. 7). The two sides of the river are connected via bridges or, alternatively, visitors can board the Venetian style gondolas to access either side (Ref. 5). In 2021, park lighting infrastructure has been extensively replaced to ensure accessibility and safety during day and nighttime (Ref. 3).

The Recovery of Green Area on Avenida del Lago is a group of activities aimed at restoring and preserving the ecological integrity of green space within an urban setting. This project involves multiple stakeholders, including the "Establecimiento Público Ambiental" (EPA) Cartagena, "Fundación Verde Que Te Quiero Verde", Asopopa, and local businesses such as Crepes and Wafles and Centro Comercial Caribe Plaza. The primary focus is environmental restoration, sustainable urban mobility, and public space recovery (ref 1). The project aims to rehabilitate the degraded green spaces along Lago Avenue by enhancing urban greenery, restoring mangrove ecosystems, and improving public access and mobility. It also focuses on reducing pollution, preventing informal waste disposal, and raising environmental awareness among local communities and businesses. These activities align with broader efforts to promote ecological sustainability and enhance urban resilience (ref 1, 3). Since 2020, activities have included the planting of trees, mangroves, and other native vegetation in the green spaces of the avenue. Regular clean-up campaigns have been organized to remove solid waste, and community education programs have been conducted to promote environmental stewardship (ref 2). Previously, Lago Avenue was an area plagued by pollution and homelessness, and with the project, the intention is to gradually transform the area into a wooded area or productive park (ref 2).