Implement measures that prevent/manage desertification, soil erosion and landslides

Peru has seen a sharp increase in major flooding, prolonged droughts and water scarcity of supplies in the dry season, negatively impacting agriculture, migration, conflict and economic growth in recent years. As 71% of the world's tropical glaciers are found in Peru these climatic changes affected the country profoundly leading to a decrease in the glacial surface and creating unstable lagoons also causing natural disasters such as alluvium landslides and deadly flash foods. Glacial melt is also disrupting water flow and quality, posing a threat to the flora and fauna that rely on freshwater environments. Unsustainable management of fragile glacier ecosystems is causing environmental degradation and biodiversity loss. To counteract many of these challenges and to safeguard the communities that are in peril, in 2011, the Government of Peru together with a number of stakeholders, initiated an intervention to sustainably manage more than 200 new lakes that affect directly populations in different cities in the Ancash, Cusco and Lima regions, Huaraz being one of the cities targeted. The project benefitted downstream communities and protected fragile high-altitude freshwater ecosystems. (1,2)

The Jerusalem Forest is located southwest of Jerusalem and is the green lung of the residents of Israel's capital. The forest has a variety of trees, flowers and wildlife, remains of ancient farming implements and burial caves (2). The forest was planted in the 1950s in an attempt to increase the green cover and natural biodiversity of the area. However, due to intensive urban development including road constructions and energy grid installation and forest fires the size of the forest has been shrinking once covering 4 700 000 m2 to the current size of 1 250 000m2. In 2016, a non-governmental green organisation initiated the renewing of the Jerusalem Forest with the aim to preserve the forest, halt its decrease, secure its sustainable maintenance while involving the public in the conservation efforts increasing their environmental knowledge about their local habitat and support nature stewardship through the application of a community forest model. (1,2,8)

As of 2011, Windhoek, the capital of Namibia, has a population of approx. 330,000 people. By 2018, an estimated 40% of Namibia’s 2.4 million population were living in shacks and Windhoek makes no exception. Approximately 30% of the capital population lives in unplanned informal settlements struggling to access basic services such as water and sanitation. Worse than that informal settlements are especially vulnerable to environmental hazards: they are squeezed in next to each other on the slopes of mountainsides. When there's the occurrence of floods, they do so with such force and wash away people’s homes and their belongings. Even more distressing, people often lose their children due to rapid and unannounced flash floods. As a response to these threats and challenges the inhabitants of an informal settlement, Onyika (located in Okuryangava - which is a suburb of Windhoek, situated in the north of the capital city) paired with local authorities, donors and climate change experts to embark on a community-led process of creating a climate-resilient community. Being especially vulnerable to climate change, these forms of settlements require special attention in the development of climate resilience strategies. (1, 6)

Medellin is the second-largest city in Colombia. The city used to be one of the most dangerous in the world, as Pablo Escobar founded here the Medellin cartel. After the death of Escobar, the city's homicide rate has decreased by 95% and extreme poverty by 66%, thanks in part to a string of innovative mayors who laid out plans to integrate the poorest and most violent hillside neighbourhoods into the city centre in the valley below. The same innovative mayors realised that Columbia and its cities are very vulnerable to climate change being located in a tropical zone and is influenced by El Niño and the La Niña. In Medellin, the municipality has built upon a tradition of planning to become an urban lab for the construction of public life with the aim of inclusive, peaceful and sustainable development. As such starting in 2008 Medellin began implementing a green strategy whose goal was the creation of a green belt around the city as well as waste control. The intervention discussed in this case is one initiated in 2014 when the municipality carried out planting and reforestation projects for the protection of the eastern slopes of the city. (1,2,3)

The Porsuk Stream divides the city of Eskişehir into two with a green corridor running along the shores of the stream. The Porsuk Stream served provisioning services and acted as a recreational area in the first half of the 20th century, however with increased industrial activities discharging untreated wastewater into the river, rapid urbanisation in the city and other settlements, and increased fertilisers and pesticides in the groundwater originated from agricultural practices (upstream of the Porsuk River), it became highly polluted and its ecosystem degraded severely (1,2,4,5). The Organization for Security and Cooperation in Europe (OSCE) identified the stream as one of the highly dangerous rivers in terms of pollution and health, where no living beings except viruses live (1).
Within the framework of the 'Eskişehir Urban Development Project' the 'Natural Disaster Loss Reduction Project (Porsuk Project)' has been initiated focusing on the ecological restoration of the stream, improving water quality, increasing the resilience of the city against natural disasters (as earthquakes and floods) while also reestablishing the stream's environmental and social role in the city (1). A network of natural infrastructure was created along the Porsuk by expanding public green spaces and link the entire corridor with a sustainable public transport network. (4,5)

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).

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).

The project is part of a bigger initiative aimed at restoring the coastal forest near the city of Mahajanga in western Madagascar. Alongside 2 international NGOs, the community located in the bay next to the city of Mahajanga implemented the intervention with the ultimate goal being to transition the land into a protected area as part of the greater "Mahajanga Green Belt Project". The regrowing forest will form the northwestern end of the greater Mahajanga Green Belt, with the southeast meets the Ankarafantsika National Park. The project also has a gendered aspect as it aimed to employ mostly the women in the suburbs of the city. (1,3)

Quelimane is a port city in Mozambique. It lies below sea level right alongside the Good Signs river (Rio Bons Sinais), and just a few kilometres from the coast. The frequent extreme weather phenomena such as rain and marine flooding render the city extremely vulnerable to climate risks. In 2013, the municipality concluded that one solution involves restoring large areas of mangroves, which act as a nature-based solution against flooding, helping to stem the tide by preventing soil erosion. In the past mangroves were cut down by the locals for building and cooking but now with the help of the municipality and local communities, the trees are restored and used as the first line of defence against climate change (1).