Green densification model

As a solution to the increasing population, pollution and high energy consumption, the municipal government of Shiraz has launched the Green City project in 2008. The main aim of this initiative is to reforest the city's periphery and encourage citizens to plant gardens on rooftops and the private sectors to adhere to the city’s development plan with all construction projects. [1]

The Urban Micro-Lungs is an Urban Living Lab project in the East of Amman, Jordan that applies the Miyawaki methodology for afforestation to create new green spaces. As part of the project special urban forests were created with the aim to improve the quality of life in dense and deprived urban areas, tackle climate change caused problems such as the urban heat island effect while also supporting local biodiversity. The project was initiated by the Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) on behalf of the German Federal Ministry for Economic Cooperation and Development (BMZ) in cooperation with the Ministry of Environment and the Greater Amman Municipality, TAYYUN Research Studio (1,3,4). While the project was just completed in 2021, "the Urban Living Lab has shown the feasibility of creating green spaces even in adverse conditions characterised by dense construction, high degree of surface sealing and lack of open spaces." (1)

Recognising the benefits which urban forests bring to its citizens, Salvador has committed to protecting and restoring the Atlantic Forest, and has developed its own local framework which goes beyond national requirements (Ref. 1). The city has launched several programmes under its 'Salvador, Capital da Mata Atlantica' initiative, which together aim to restore the forest which has "suffered from severe deforestation" (Ref. 1). Included under the umbrella initiative are programmes such as the "'Delivery of trees', recovery of parks and collective planting" (Ref. 4).

The intervention targeted a section of the Dominguez Creek for restoration, with the aim of achieving a "multi-benefit project [which] creates passive and active recreation opportunities for park-poor communities, reestablishes native riparian plantings and captures stormwater before entering the channel along the Dominguez Creek in cities of Gardena and Hawthorne" (Ref. 2). Previously being characterised by the local community as a “Triple U” (Undesirable, Unsafe and Unusable) area, the project aimed to support a variety of environmental, sustainability, and humanitarian activities (Ref. 1). The nature-based solution interventions which were implemented as a result of the project mainly pertained to the planting of in situ trees, shrubs and groundcover plants; restoration of the riparian habitat; temporary installation of a "mini-urban forest for a shaded respite from the harsh downtown streetscape"; aiding in stormwater capture; conservation of water resources through using native plant species; and creating "watershed awareness" (Refs. 1, 2, 4, 5 and 8).

Senegal, like many other West African countries, is in an unprecedented position when it comes to the threats climate change poses. Climate scientists predict that the country will likely experience increased temperatures, decreased annual rainfalls, a rise in sea levels, and an increased frequency of heavy rainfall events. Automatically these events will change drastically the social and economic structures of the country and are reasons for concern for the people of Senegal and their government. For example, the city of Thiès is in an area where environmental degradation is very advanced. The tree cover is in a situation of extreme fragility due to tree ageing or abusive tree cutting. To address many of these concerns, the city of Thies is trying to become sustainable through the development of green spaces that are expected to restore the city's ecological dimension and contribute to the reduction of greenhouse gases and the improvement of the living environment. (1,2)

The Sustainable Residential Complex project was a measure taken by the city of Dubai, one of the largest city ecological footprints, with a goal to reduce it to the smallest ecological footprint by 2050. For the past two decades, the UAE government has made an effort to lower its own dependency on fossil fuels, shifting toward more environmentally-friendly sources to power its cities. The sustainable residential complex development project is one of the few initiatives taken by the city administration of Dubai under Vision 2021. Located just outside Dubai the area is the first operational net-zero energy residential complex in Dubai. [1, 2]

Campinas is a fast-growing city and like many cities in Brazil, it confronts itself with many climatic incidents linked to a hotter and drier climate. In Campinas, in spite of the good performance of the city and the region in economic areas, there is a historical lack of urban landscape planning that integrates adequate social housing and areas that should be protected, such as riparian corridors, ecosystem remnants and other relevant green areas that offer ecosystem services in the urbanised context. Campinas has developed plans, projects and programmes to tackle regional, municipal and local issues related to environmental quality and offer green areas to the least privileged residents. Ecological corridors are being designed to connect forested fragments and/or relevant ecological areas to enable the genetic flow. The municipal green plan adopted the concept of a connectivity line to promote ecological corridors. (1,2)

Under Sustainable Development Goal 11 (make cities and human settlements inclusive, safe, resilient and sustainable) in 2017 a coalition of stakeholders including the Municipality of Asuncion started the implementation of an initiative focused on improving the quality of life in the Metropolitan Area of Asunción through green infrastructure in a sustainable and resilient city framework. Why Asuncion? Cities and metropolitan areas are fundamental centres of economic growth: they contribute approximately 60% of world GDP. However, they also account for around 70% of global greenhouse gas emissions and more than 60% of resource use. Asuncion makes no distinction - it is a city with a high flow of cars and transportation, irregular flooding (the sewerage system there has already been exceeded for some time), and urban growth. Trying to respond to some of these challenges, the present intervention has been proposed with a duration of 5 years. (1,2)

Douala is the economic capital of Cameroon and one of its largest cities. The city is located on the banks of the Wouri River (hence a port city) and its climate is tropical. The marine and coastal biodiversity of Cameroon is rich and diverse, and it is highly endangered because of human activities including artisanal and industrial fishing and pollution generated from industries, accidental loss of crude oil in transit or during loading or unloading. In Douala, thousands of inhabitants have settled in and around the mangrove swamps, destroying the mangrove ecosystem and endangering biodiversity including snakes, birds, fish, trees and frogs. Biodiversity studies are rare, and even if they exist, they are done in part and do not give an overview of the real state of biodiversity in the city. The city of Douala is full of many ecosystems of various natures (micro-ecosystems), each of which has species adapted to the environment. Besides this, Douala confronts itself with seasonal flooding and high temperatures due to climate change. In response to some of these challenges, a local entity, the Association of academics and researchers for Biodiversity conservation, initiated in 2020 an action that focused on environmental education and biodiversity conservation. The initiative also provides a framework for reflection and exchange on biodiversity issues. (1,3,4)

In 2019, in the city of Ulan-Ude, the most comprehensive and large-scale action "Green City" was launched [2,3,4,5,12], with the goal of creating an efficient and sustainable greening system in Ulan-Ude [1,7]. Nowadays, according to the city's norms, there are two times fewer green spaces per resident than is customary [7]. According to this program, by 2024, the provision of the population with public green spaces should be 10 sq. m per person [1,8]. Within the framework of the project, effective technologies for greening are already being introduced, and all green spaces growing in the city are being monitored [3,5,6]. Planting of green spaces is carried out under the guidance of the Scientific and Technical Council for the Integrated Greening of the City, which includes Buryat scientists and specialists from the City Administration [2].