Joint implementation (e.g. tree planting)

Once empty paved area between the houses on Marat Street in St. Petersburg now has been turned into a cosy green garden [4, 5, 6]. The project was developed by a group of students and initiated by the Green Petersburg Foundation, Plants for Friends, "Vladimirsky" Municipal District and others [1, 3, 4, 5]. The square landscaping project contributes to the city's adaption to climate change, a need to increase urban green zones, reducing excessive heat and rainfall levels, and the creation of habitat for birds, among others [3]. The square acquired the concept of a harmonious combination of natural motives and the mood of the Russian landscape [4].

One of Valdivia's (in South Chile) southern peripheral neighbourhoods reaches the river of Angachilla which in time led to the creation of an urban wetland, a beautiful and large urban nature reserve of the city of Valdivia. The city of Valdivia is inserted in an extensive network of rivers and coastal wetlands, which penetrate the city through estuaries, hualves and meadows. The Angachilla estuary wetland is one of the most important, connecting the southern sector of the city with the Valdivia River estuary.
These urban wetlands provide important ecosystem functions that directly benefit citizens. Since 2007, the residents of Villa Claro de Luna (neighbourhood) together with various social organisations have worked on the recovery of the Angachilla Wetland, a natural space of great ecological and social value located in the city of Valdivia. Actions included carrying out cleaning, restoration and environmental education activities to recover a place that, abandoned and without any protection from the authorities, was converted into a clandestine garbage dump. (1,2,3)

From 1998-2002 Argentina went through an economic depression, which began after the Russian and Brazilian financial crises, caused widespread unemployment, riots, the fall of the government, and a default on the country's foreign debt. Rosario, the third-most populous city in the country, was not a stranger to the crisis' effects as many of its inhabitants were now living under the poverty line. Coupled with this, climate change was heating up the city and making rainfall more erratic, leading to both flooding in Rosario and fires in the nearby river delta. To tackle urban inequality and climate change the Municipality of Rosario developed a program called "Urban Agriculture Program" which aims to give low-income residents access to underutilized and abandoned public and private land to cultivate food. Over the years, the municipality evolved the program into a cornerstone of its inclusive climate action planning. (1)

The city of Algiers initiated in 2010 a project in order to establish a green belt around its areas and some northern municipalities. The project aims to create agro parks, allotment gardens as well as parks as a strategy for reintegrating the concept of the green belt into the Algerian territory. Through this intervention, the municipality aims to put into practice environmental values ​​linked to improved quality of life and social well-being, for the benefit of the local community. The intervention plans to introduce different species of trees and include for the first time in Africa agro parks as spaces which are designed to reconcile urban and agricultural functions in a win-win strategy. The action was thought to respond to the impacts of climate change in the country, which faces rain events that are less frequent but more intense, and droughts that are more common and longer. (1,2,3,4)

The Orbital Forest of Tirana is an innovative urban forest that as a green belt forms a natural growth boundary for the City. Tirana has experienced rapid development in the past decades that led to population growth challenging municipal services and infrastructure, while climate change also posed extensive pressures to the urban area with intense flooding, precipitation, urban heat and degrading environment (1, 4). The Orbital Forest is a ring on the periphery of the City that connects 14,000 ha of Tirana’s parks, agricultural fields, and forests, maintaining the ecosystem and supporting biodiversity. (3, 4) The NBS aims to increase urban greenery through the plantation of 2 million trees that fit well to the existing ecosystem while also creating a natural boundary to halt urban sprawl (1,4,5). The afforestation of the Orbital Forest has been done through the “Donate a Tree For Tirana” campaign started in 2017 where citizens, businesses and international organisations can plant a tree adding to the green belt. As of 2021, more than 440,700 trees in the framework of the "Donate a Tree" campaign are also bringing urban nature closer to residents (3).

Climate change has become the day-to-day struggle for this nation - an island nation that faces serious sea-level rise implications should the problem remain uncurbed. The impacts seen are related to rising temperature, sea-level rise (coastal erosion), and changes in rainfall (flooding). To reduce the vulnerability of the population of two regions next to its capital (Victoria), the Ministry of Environment and Energy of Seychelles initiated in 2012 a project aiming at improving the quality of life for the people of Seychelles and restore coastal zones as well as the ecological habitat related to them through nature-based solutions. The project will reduce these vulnerabilities by spearheading ecosystem-based adaptation as climate change risk management—restoring ecosystem functionality, and enhancing ecosystem resilience and sustainable watershed and coastal processes, in order to secure critical water provisioning and flood attenuation. (1)

Mauritius is a biodiversity hotspot, which has been declared by IUCN as a “Centre of Plant Diversity”. 39% of plants, 80% of non-marine birds, 80% of reptiles, and 40% of bat species on the islands are reported as endemic. (4) Nevertheless, human activity keeps threatening this endemicity in Port Louis, a port city and the capital of Mauritius. The city is surrounded by a semicircle of mountains on one side and the Indian Ocean on the other. In 2006 a local NGO started implementing an initiative that focused on restoring native vegetation to the hill that harbours the capital and it's also the place of an important historical heritage, the Fort Adelaide. (2)

The redevelopment of the Bishan-Ang Mo Kio Park (Singapore) saw the naturalisation of the previously channelised Kallang River, as well as the installation of wetland cells as water cleansing biotopes and creation of butterfly habitats (Ref. 1).

The Kallang River was previously confined to a concrete canal that ran to the southern edges of Bishan-Ang Mo Kio Park (Ref. 1). The channel segregated the two residential areas situated on either side of the park, with the river's 2.7km continuous concrete channel being crossable at only certain defined points (Ref. 3). Following its naturalisation, culminating in 2012, the now 3.2km meandering river is considered the park's highlight, "merg[ing] seamlessly with the park's greenery" (Refs. 1 & 6), and creating a "blue-green recreational network which is well-integrated with nearby residential areas" (Ref. 2).

In 2019 at the Gullele Botanical Garden in Addis Ababa, the Ethiopian government launched a historic tree planting campaign. Over 350 million trees were planted in an ambitious move to counter the effects of deforestation and climate change. The Gullele Botanical Garden was selected as one of the 1000 sites all over the country involved in the Green Legacy Initiative, a national campaign against the effects of climate change. The United Nations estimates that Ethiopia’s forest coverage has declined drastically to a low of just 4 per cent in the 2000s from 35 per cent a century earlier. (1,2) The Botanical Garden was not selected aleatory as it is Ethiopia's only botanical garden and it is a nursery for various indigenous plant species. Its mission is to conserve and promote the Ethiopian diverse plants and tree population and it is a conservation initiative located at the northwestern tip of the Addis Ababa City Administration. The site covers an area of 1000 ha which is representative of the central plateau of Ethiopia. (3)

This intervention was initiated in 2014 in Agege, a slum and a city in itself belonging to Lagos. Agege is one of the 7th most populated low-income communities in Lagos with a total population of around 1,033,064 people. Climate change in Nigeria led to seasonal droughts and floods, causing pressures in terms of food security as well as high temperature and humidity levels which affect directly the economically disadvantaged population in the slums of Lagos. In 2014 a research team at the University of Cardiff alongside community leaders of a Yoruba community in Agege implemented a study on vertical gardens in residential areas with the purpose of alleviating local temperatures and enhancing biodiversity. The implementation started with a study and was continued with the introduction of practical gardens maintained by the local community of 3 residential buildings (one in Suru Street, another in Lagos Street in Agege, and a third in Abeokuta Street). (1,2,3,4)