Green densification model

The municipality of Ciudad Juarez, in collaboration with UN-Habitat, has drafted a redevelopment strategy for an area known as "Paso de Oñate." This intervention falls within the broader framework of "Vision Ciudad Juarez 2040." The plan involves constructing a forested green belt along the southern edge of the Rio Grande (/Bravo) in the northwest part of Juarez, bordering the USA.
Currently in the planning stage, the project aims to restore the ecological function of various degraded areas along the Rio Grande, transforming them into a continuous, green, walkable, and recreational space. The strategy includes allowing vegetation to recover, introducing native plant species, and increasing tree cover to rehabilitate unmaintained parks, derelict areas, and degraded riverbanks. These areas will be equipped with new features and integrated with existing parks, schools, and playgrounds. The envisioned green corridor will enhance walking conditions, improve the perception of safety, offer recreational opportunities for all age groups, and deliver valuable ecosystem services such as temperature regulation, improved air quality, and water retention.
In addition to its ecological goals, the project has a historical and geographical dimension. It aims to incorporate cultural heritage elements, such as the monument of the New Citizen, Paso de Oñate, Turtles Park, and the beginning of the Acequia Madre. It will also connect with other green space initiatives, including the Mega Park "El Chamizal" and the "Corredor Cultural," which runs through the city center.
This intervention is being prioritized due to the area's ongoing social and ecological decline. Paso de Oñate is a critical border crossing point, which negatively affects mobility and air quality. The area also suffers from a high concentration of vacant housing, which contributes to the residents' perception of insecurity. (Ref. 1, 2, 3, 4)

In 2018, a group of residents from Sector II in the Villa El Salvador district initiated a communal effort to transform an abandoned space into an urban garden (3). This is how Ayllu 21, the first community-based agroecological garden in Villa El Salvador, was born. The project was spearheaded by a group of mostly migrant senior women who decided to dedicate their time and labour to reclaiming a landfill space, to turn it into a productive green area (1). Their philosophy is rooted in the concept of "ayllu," a Quechua word signifying family, collective identity, solidarity, and respect for the environment to foster harmonious coexistence (3).
Today, Ayllu 21 spans 1400 square meters and features 40 plots where agroecological practices are employed (1, 3). The garden aims to become a space for comprehensive development, through promoting environmental awareness, political advocacy, and the fight against gender-based violence in a district that ranks third in the number of violence cases (1).
The vegetables produced are primarily for self-consumption, with any surplus distributed among neighbouring families. If there are any sales, the profits are shared among the members, who work an average of two days per week in the garden (3).
This space seeks to strengthen socialization among women and seniors and foster learning and community-building among neighbours through agriculture. It was initiated with the support of IPES Promotion of Sustainable Development as part of the Sowing in the Desert program (3, 6), and it has received support from a diversity of programmes, such as the framework of the Women United for Food and Environmental Security (MUSA) (1).

At the beginning of the twenty-first century, Kunming’s urban planning faced major challenges, including fragmented development, environmental degradation, and limited green spaces (Ref 1). In response, the municipal government launched a series of strategic plans aimed at promoting high-quality urban development and environmental restoration.
Baisha Lake was identified as a key area in these strategies, with plans for Baisha Lake Park first highlighted in 2017 (Ref 2) and reaffirmed in the "Opinions on Supporting High-Quality Development in Kunming" in 2021 (Ref 2). To implement parts of this broader strategy, the government entered into public-private partnerships. In 2018, land development rights for parts of East Baisha Lake were granted to Dahua Group, on the condition that 40% of the area be reserved as green space and that ecological restoration efforts be undertaken (Ref 3, 4).
The Eastside Baisha Lake Park project, launched by Dahua Group in February 2023 (Ref 3, 5), is thus one component of this larger government-led urban renewal effort. The project follows the city's planning framework of “one lake, six zones, 46 scenic nodes” and includes 55 hectares of green space, with 40% designated as parkland. By the end of 2023, 6.5 hectares had been completed, and the south bank of the park opened to the public in September 2023 (Ref 3, 6).
The broader East Baisha Lake area's development was originally planned by the state-owned Kunming Urban Construction Company, but land rights were later transferred to Dahua Group. Thus, while a private developer is leading the construction, the project remains a part of Kunming’s publicly driven strategy to restore the lake and enhance urban livability.

Fondo Unido Chihuahua, in collaboration with its corporate partners, is committed to raising awareness about environmental care and reforestation. One of its flagship initiatives is the annual tree-planting campaign, "Planting Today to Have Oxygen Tomorrow," organized by United Way Chihuahua in Ciudad Juárez. This environmental initiative focuses on improving the quality of different urban green spaces (parks, school grounds, streets) while fostering ecological awareness in vulnerable communities across the city. The primary objective is to plant a significant number of trees throughout Ciudad Juárez, using native species that are water-efficient and well-adapted to the local climate and soil. In 2022 the initiative aimed to reforest 18 parks located mainly in the south-eastern part of this border city with 1,000 trees. In 2023 and 2024 the intervention focused on planting 850 trees scatted all over the city.

The campaign brings together donations and volunteers through partnerships with various stakeholders, including local and regional governments, private companies, community organizations, and the general public.
United Way Chihuahua oversees the planning, coordination, and logistical efforts for the campaign. On planting days, volunteers gather at designated sites, guided by the organization to ensure successful planting efforts and community engagement (Ref 1-4).

The Miraflores Bicentennial Park has been built on the Malecón de la Reserva and the Quebrada de Armendáriz. It was inaugurated in June 2022 as one of the created projects within the framework of the commemorations of the 200 years of Independence celebrations (1). It is considered a new green lung of Lima (2), as it has a green area of 30,400 square metres and stands on one of the cliffs of the Costa Verde (1). It has a system of terraces that replicates the construction model of the Incas, which has made it possible to additionally reinforce the soil and the slopes with the use of retaining walls up to 10 metres high, with horizontal geogrids and vertical geocells (1, 2). It was structured on a stabilised slope in order to mitigate the risk of landslides (4), and an irrigation system was implemented to stabilise the soil (4).
This space was built as a biodiversity garden with more than 160,000 xerophilic coastal species with low water consumption, 300 trees and 80 palm trees. It also offers places for tourism, such as viewpoints and squares, where cultural events, open-air activities and rest areas are held (1). It also aims to connect aspects of landscape conservation, preservation of biodiversity in the city, and the construction of a cultural landscape in which human action is complementary and friendly to the natural environment (9). Finally, it seeks to contribute to the reduction of the municipality's carbon footprint by reducing the harmful effects of urban expansion on the Lima cliff ecosystem, such as deforestation, water pollution and loss of biodiversity (9).

In 2023, the municipality of Cagliari initiated a project to transform 50 school gardens into vibrant, multifunctional outdoor spaces that enhance education and recreation. Co-funded under an EU program, this initiative aims to create environments where students can learn and play outdoors, taking advantage of the city’s favorable climate. The gardens are being upgraded with new features, such as trees, educational vegetable plots, diverse plant species, playground equipment, and furniture, to provide versatile spaces for learning, sports, and play.
Automated irrigation systems are being installed in each garden, conserving water by adjusting based on soil humidity and detecting leaks. This technological upgrade ensures efficient maintenance of the green spaces.
Overall, the project seeks to enrich the educational experience by integrating nature into daily school life. It aims to promote students' physical and psychological well-being through more opportunities for outdoor learning and activities, fostering a connection with nature, and improving the overall quality of the school environment (Refs. 1, 2, 3, 4 & 5).

The Ciénaga de las Quintas is a coastal wetland located alongside one of Cartagena’s main roads, adjacent to the public market square and situated between the Jiménez and Bazurto Bridges. It is home to two predominant mangrove species (Ref 1). The wetland currently faces pollution problems because it is used for the disposal of solid waste, such as plastics and construction materials, and it receives wastewater and household garbage from nearby residences. Las Quintas is also the main waste disposal area for the Bazurto market, which handles 43,430 tons of food products each month (ref 3). The recovery initiatives for the Ciénaga de las Quintas are led by the Environmental Public Establishment of Cartagena (EPA Cartagena) in collaboration with other public institutions, the private sector, and citizens, with the main goal of achieving the ecological restoration of the city's water bodies and to maintain and preserve our mangrove ecosystems (ref 2). Since 2020, key implementation activities have included the removal of solid waste, planting of native tree species, dismantling of informal structures within the mangrove zone, and the rehabilitation of areas previously occupied by debris (Refs 4, 5).

For a Forest in Your Neighborhood" is an afforestation campaign by the DDOR insurance group, launched in 2022 as part of their Environment, Society, and Governance (ESG) commitments (Ref. 1). Site selection was based on online votings, with thousands of votes being casted from 188 towns across Serbia (Ref. 2). In the end, the fifteen most popular cities were selected for project implementation. As a result, hundreds of trees were planted, including 25 trees along the promenade of Belgrade’s Ušće Park in 2023 (Ref. 3). Ultimately, the initiative aims to create and enhance urban green spaces, to improve air quality and living conditions in Serbian cities (Ref. 5). The success of the campaign encouraged DDOR to extend the campaign in 2024, financed through their eco-insurance schemes (Ref. 4)

Due to rapid urbanization and development, cities in China, including Kunming, face challenges in managing neglected urban spaces, particularly vacated demolition sites and leftover land (Ref 1, 2, 3). To address this issue and enhance residents' well-being, Kunming has created 400 pocket parks since 2022, transforming forgotten corners into vibrant green spaces (Ref 4, 5).
One of these parks, Wenxing Pocket Park in Xishan District, was built in 2023 on 2.3 hectares of land (Ref 6). Located next to a secondary school and two protected historical relics, the park not only preserves historical heritage but also reflects cultural value (Ref 6, 7). In addition to increasing urban green spaces, the park provides recreational and physical facilities for residents, children, and students (Ref 6). Its design is inspired by traditional architectural styles and incorporates wood craftsmanship, as well as ecological sponge facilities (Ref 6, 7).
The park also features science gardens, promoting awareness and knowledge of herbs and sustainability (Ref 6). The project employs methods such as infiltration, stagnation, storage, purification, and drainage to manage rainwater effectively. By utilizing the natural terrain, it creates ecological dry streams and sunken gardens that absorb and store rainwater, helping to control runoff. This approach aligns with the "sponge city" concept, promoting natural water accumulation, infiltration, and purification.
Additionally, the integration of various plants enhances the microclimate, supporting local wildlife and creating a healthy, vibrant public space. The Wenxing Pocket Park has been implemented by the Municipality of Xishan. (Ref.6,7)

The requalification project for Viale Buoncammino in Cagliari aims to revitalize the historic promenade while preserving its original layout and functions. Launched in September 2022 and completed in 2023, the project focused on enhancing the area’s aesthetic and environmental appeal. Key improvements include expanding green spaces by adding 560 new square meters, enhancing vegetation, and reducing surface runoff. This involves increasing permeable surfaces around existing trees to boost natural vegetation, improve bioclimatic comfort, and manage runoff during heavy rains.

The project also includes reconstructing pavements, optimizing seating areas, and repositioning urban furniture for better functionality and aesthetics. A modern LED lighting system will be installed to reduce energy consumption and operational costs, supporting the project's sustainability goals. The area is included between via Anfiteatro, viale Buoncammino and viale Giussani and also includes the squares F.Pilia and Marongiu-Pernis. The project aims to restore Viale Buoncammino as a dynamic social and cultural hub in Cagliari, appealing to both residents and visitors. (Refs. 1, 2, 3 & 4).