Green densification model

A new nature sanctuary was unveiled at the Kingfisher Wetlands, Gardens by the Bay, in Singapore in 2021. Before the sanctuary was created, the original site was a popular bird-watching spot for the birding community and nature photographers. However, it was isolated and "often missed by the general public". The new Kingfisher Wetlands was thus developed with the aim of enhancing and enriching the Gardens, as well as providing new nature areas for visitors to explore. The place is a new hotspot for the flourishing diversity of exotic flora and fauna. Furthermore, the project helps in mitigating climate change through mangrove plantations. Over 200 native true mangrove trees and mangrove associates have been planted, contributing to sustainability by storing “blue” carbon. Additionally, the project actively supports research into blue carbon science. This contributes to the country's effort to transform Singapore into a City in Nature by weaving nature more intensively into the urban fabric. [1, 4]

The Chulalongkorn University (CU) Centenary Park was created to provide a green space for the city and celebrate Chulalongkorn University’s 100th anniversary. Located in the centre of shopping and commerce, the park is designed as a multi-functional “urban forest”, which serves as an oasis for the residents and visitors of Bangkok, who can spend quality leisure time in a lush and pleasant environment. The park includes constructed wetlands with rain gardens, retention ponds, an underground water drainage system and green roof areas. Opened in 2017, Chulalongkorn Centenary Park is the first critical piece of green infrastructure in Bangkok to mitigate detrimental ecological issues and disaster risk reduction. Unlike other public parks around the city, this one is the first in Thailand to demonstrate how a park can help reduce urban flood risks and help the city confront climate change, all while offering city dwellers a place to reconnect with nature. Designed with various ecological design components, the park reminds the city of ways to live with water rather than fear it. [1, 2, 4]

The Rioni River basin is the second largest in Georgia, originating in the Greater Caucasus range and flowing into the Black Sea, traversing the town of Samtredia. Samtredia has been affected directly on many occasions by floods that have become a current occurrence in the Rioni River basin as of late. The underlying causes of vulnerability to climate change in the Rioni basin can be categorised into 1) physical factors –direct manifestations of climate change, 2) factors caused by anthropogenic intervention – those related to the harmful ways in which humans have and continue to interact with the environment which has exacerbated vulnerability and 3) Institutional factors – related to the legislative/regulatory barriers placed by government and other institutions, as well as limited capacity (human and resources) to manage climate change vulnerability. Flooding has been harmful not only to the local population but also to the biodiversity of the area, which suffered losses and an ecological imbalance and a disruption in the habitat patterns of local fauna. Many of these issues became the focal point of an activity developed by the Adaptation Fund alongside the Georgian government as early as 2012. The intervention stretched for 4 years and involved several localities in the Rioni River Basin, including Samtredia municipality, consisting of creating bank terracing, vegetative buffers, and tree revetments in order to address floods related to the Rioni River basin and the localities it traverses. (1,2)

The construction of "the biggest vertical garden in Uruguay" was completed in 2014 (Ref. 1). The vertical garden has an area of 300m2 and contains over 6,000 plants, of which most are endemic, comprising 35 species and 10 different families (Ref. 2). In addition to being aesthetically pleasing, the garden is intended to reduce temperature, produce oxygen and offset greenhouse gas emissions. It is thought to "contribute...to the filtration of approximately 165 tons of gases per year and [be] capable of producing the necessary oxygen for 255 people, in addition to trapping 130 kilos of dust" (Refs. 2 & 3).

The main rivers that cross Lilongwe are the Lilongwe, Lingadzi, Nankhaka and Chankhandwe Rivers, of which the Lilongwe River is the biggest and longest river and the primary source of water for Lilongwe city's residents. At 200 km long, besides its primary function, the river also supports several informal settlements and provides ecological, recreational, cultural and economic benefits. Despite these important functions that the river offers, it is still facing threats such as pollution, urban agriculture, sand mining, climate change effects, and a loss in the biodiversity of fauna and flora that this watercourse hosts. As it sustains a population of approx. 1 mil. inhabitants, the local authorities were interested in finding solutions to address the above threats. As early as 2016, ICLEI ( Local Governments for Sustainability), an international NGO that promotes sustainable development, worked alongside Lilongwe City Council and other stakeholders to protect the river as well as the people depending on it and implemented several actions, with the help of the local community. Eventually, this collaboration led to the issuing of a strategic plan for a sustainable and functional ecological corridor system in the heart of Lilongwe City. The Ecological Corridor aims to transform Lilongwe into a green, clean, prosperous, and resilient city, by ensuring the protection of its urban natural assets, and advancing complementary nature-based solutions. 1,2,3)

Typically considered dividers of the urban space, ravines ('barrancos') which run through Guatemala City are being targeted for an overhaul of their reputation and are instead being reframed as a way to bring people and their environment together (Ref. 3). Now metamorphosed into a grassroots movement, 'Barranqueando' "wants to continue integrating the ravines with the urban environment to generate ecological, social and economic benefits for their city", where the unexplored potential of the ravines can be realised as areas to "serve as natural reserves, as nodes and paths for sustainable mobility throughout the city, as rainwater collectors, as crucial carbon sinks, as well as for purifying and cooling the air" (Ref. 3).

One of the first projects of the movement was the development of Jungla Urbana, an ecological park that brought together a ravine and the adjacent urban space, "giv[ing] residents the opportunity to wander through largely untouched nature – and experience the natural ecology of the site their city is built on", and providing an area to "...explore how the city’s unique ecosystem can be used to benefit its citizens – ecologically, socially and economically" (Ref. 3).

The municipal government of the Yiwu city in China has launched the Green Lungs of the City Project (GLCP) in 2019. The overarching goal was to build a green lung, which will create more green spaces for residents in Yiwu, mitigate environmental pressures and improve the city's resilience to climate change. Under the project, a green corridor was created to reconnect the roads, rivers, ponds and lakes where different tree species were planted. Additionally, wetlands were constructed and restored to improve resilience against climate change disasters. The project is still in the ongoing phase, and a forest-wetland ecological park is under development in the city's central area. The GLCP aims to use different types of NBS elements to promote sustainable urban development and to provide multiple ecosystem services to the citizens in a highly urbanised area. [1]

The marshes in southern Iraq, formed by the Tigris and Euphrates Rivers, are home to one of humanity’s oldest cultures, once the third-largest wetlands in the world. The Eden In Iraq wastewater garden project started as a humanitarian project that has developed as a necessity for the people of Al Chibaish and the localities surrounding the town. This water remediation project holistically looks at wastewater, trying to include this type of water and its nutrients in a sustainable form by using it to create green spaces. The Eden project in Iraq regards human waste as a valuable source of nutrients and freshwater, which can add to local greenery and landscape beauty if properly treated close to its source. From a climate change point of view, the project focuses on the creation of a wetland with wastewater that can support a garden within the marshes of Iraq. Marsh restoration is a powerful tool against warming temperatures and loss of vegetation, especially in arid areas such as Iraq. From a biodiversity point of view, the project bares a great deal of significance as marshes support a myriad of rare wildlife and rich biodiversity. (1,2,3)

Beirut RiverLESS, a project initiated by OtherDada, aims to address the deterioration of the Beirut River and its negative impact on the surrounding communities and environment by developing a holistic response plan for the Beirut River Watershed. The river runs east to west, then curves north, separating the city of Beirut from its eastern suburbs, primarily Bourj Hammoud and Sin el Fil. The goal is to bring the Beirut River back to life by following a Landscape Ecology approach and by enabling local governance, leading to innovative ecological interventions. Throughout time, the river has been used as a water resource for drinking and irrigation. It also once had an important role as a space for recreational activities. In 1968, the river was transformed from a natural, healthy and performing ecosystem to a canalized infrastructure, becoming an open sewer of domestic and industrial wastewater, highly polluted and posing numerous health risks to its neighbours. The river also lost its recreational and social function as people no longer had access to it. (1)

Al Shaheed Park is the largest park in the country. The park was designed to include besides its green spaces, several buildings (museums, parking) populated with green roofs and an artificial lake. The size of the park with all the mentioned grey and green elements stands at 20 ha. The park is viewed as an encompassing part of a green belt that surrounds the city of Kuwait. From an environmental point of view, the park was built to protect the city from sandstorms and to reduce air pollution. From a cultural point of view, the park and the museums are providing the public with high-quality programs, events and spaces, and part of their mission is to spread awareness and educate the public on the importance of the country’s land, history and environment, in addition to the encouragement of international and regional exchange of arts. In addition, the park is meant to commemorate the victims of the first Gulf War. (1,2,3)