Increase green urban nature for carbon storage (wetlands, tree cover)

Mérida city developed a Municipal Green Infrastructure Plan (Plan Municipal de Infraestructura Verde), in order to "strengthen the green infrastructure system through planning, design and implementation of urban strategies at different scales of actions and projects that contribute to enriching ecosystem services in the public and private space of the Municipality of Mérida" (Ref. 1). The plan has four axes, providing a comprehensive and transdisciplinary approach to integrating nature-based solutions into city planning and the design of public spaces in order to provide climate change adaptation and mitigation benefits (Ref. 1).
The Mérida Green Infrastructure Plan shares strong ties with a state-wide strategy, 'Arborizando Yucatán', which promotes reforestation efforts across the 106 municipalities of the state in order to "help reduce the effects of climate change, have more areas green and a better climate for the benefit of current and future generations of Yucatecans" (Refs. 3 & 4). At both the municipal and state level, the relevant administrations (Mérida City Council and the State Government, respectively) have signed an agreement (Declaration for Mérida 2050), whereby both pledged to plant at least 200,000 native trees in the City of Merida, running alongside both the Mérida Municipal Green Infrastructure Plan and the Aborising Yucatán Strategy (Ref. 2).

In April 2021, the Kochi City Corporation in collaboration with the World Resources Institute (WRI) and ICLEI South Asia inaugurated the Subhash Bose Park after a thorough renovation. The project was part of the overarching project "INTERACT-Bio" by ICLEI South Asia and the KAWAKI initiative by the WRI (part of the Cities4Forests movement in Kochi). The initiative was launched to demonstrate the application of Nature-Based Solutions (NBS) for climate mitigation in Kochi. The project aims to develop urban grooves similar to the traditional grooves that once existed in Kerala. Additionally, with this project, ICLEI South Asia aimed to address the problems of climate change through mainstreaming biodiversity objectives across the city. The park plays as a major carbon sink at the heart of the city that is home to over 300 species of native trees and many more species of native plants. Furthermore, the Kochi City Corporation is focused on increasing native biodiversity and communicating the importance of this biodiversity to residents in order to ensure long term conservation efforts. This was a key motivator for the city in the conceptualization of the garden which not only improves the native biodiversity of the city but also serves as a demonstration site for nature education. The park also includes a newly built pollinator garden that has augmented the pollinator base in the city. [1, 4, 7, 10]

Delhi Development Authority (DDA) has established a network of Biodiversity Parks in Delhi with unique landscapes that harbour a diversity of plants, animals and microbes living in ecologically sustainable biotic communities and rendering multiple ecological services. Presently there are seven Biodiversity Parks developed by DDA located across the landforms of Delhi. These parks have a mosaic of habitats with rich floristic and faunistic diversity that function as a dynamic ecosystem. They have ecosystem processes such as organic matter decomposition, regeneration of plants, pollination, resting and nesting of birds and colonisation by other animals. The biodiversity parks in Delhi have proved to provide extreme essential services by creating ecological corridors and maintaining the genetic diversity in an urban setup. Furthermore, these parks have shown substantial potential in storing carbon and other pollutants and help in mitigating climate change. [2, 3]

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 Beddagana Wetland Park is located in Sri Jayawardenapura Kotte, Sri Lanka's administrative capital. The wetland park plays an important role in flood regulation and keeping the city cool during periods of extreme heat. The city is located in the Colombo district and the project contributes to the flood management goals of the Metro Colombo Urban Development Project (MCUDP). It demonstrates how a wetland can be preserved while promoting eco-tourism and improved livability in the city. The target area is located within the Sri Jayewardenapura-Kotte municipality and is a part of Parliament Lake. While focusing on the protection of the wetland habitat as a flood-retention area, the project also supports selecting investments aimed at the protection and landscaping of key areas within the target area to improve livability for local people living in and around the area, while providing access to much-needed recreational space. [2, 7]

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).

Monavale Vlei is an important wetland area within the city of Harare, characterised by miombo woodlands that play an important role in the fragile ecosystem of the Manyame catchment basin, the main supplier of water for the city of Harare and its suburbs. Throughout the years, Monavale has been subjected to a number of threats such as construction developments, dumping of waste, fires, illegal farming, invasive plants, informal agricultural practices and loss of biodiversity. To address some of these challenges the local community organized itself into a group - Conservation Society of Monavale (Cosmo) Trust, to protect the area and, with the help of the municipality of Harare and some international bodies, implemented a series of actions designed to protect the wetland and reduce the loss of biodiversity, among many others. In 2009 the NGO was awarded a United Nations Development Programme Global Environment Facility Small Grant. The intervention had 3 objectives: to restore parts of the wetlands, to advocate with the local and international authorities for the legislative protection of the wetlands, and to engage the scientific community in research regarding the wetlands. This enabled Cosmo to restore Monavale vlei to an almost pristine wetland state, and other UN funding has made possible several training and awareness projects for a wide range of audiences. (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)

To mitigate environmental pressures, including air pollution and urban heat island effects and to improve urban resilience, the municipal government in Beijing has launched the largest afforestation Programme in 2012, Beijing Plain Area Afforestation Programme (BPAP). The aim was to create huge forest patches, develop urban forest park clusters and optimise the large-scale forest patterns. By 2015, BPAP has created green strategies with nine green wedges, multiple green belts, and green corridors around Beijing's old city centre. More than 70,000 hectares of forest (more than 54 million trees) have been planted, and the survival rate has exceeded 95%. BPAP has been considered one of the most ambitious projects for a high-density urbanised area like Beijing. [1, 5]

Extensive and low-lying, Suriname’s coastal region has been identified as highly vulnerable to climate-induced sea-level rise (Ref. 1). "Momentarily the most endangered community by sea-level rise in the whole of South America and the Caribbean", the Suriname Building With Nature project has seen "wooden, water penetrable dams...being built to trap sediment and replant mangroves" (Ref. 1). Prior to the implementation of the Building With Nature project, no mitigation measures had been undertaken to protect the area, and "human interference ha[d] converted mangrove areas to agricultural land, fishing ponds and settlements", with the loss of stabilisation provided by the mangroves meaning that "the coast has become susceptible to flooding and erosion, losing up to 27 meters of land in one year" (Ref. 1). It has caused "displacement of local habitants and loss of livelihoods, [with]...the local population...and its fisheries, farms, and important religious and cultural sites [being] at risk to frequent flooding and land degradation" (Ref. 1). The Building With Nature approach is touted as being "essential for mangrove and biodiversity conservation and the enhancement of the quantity of the blue carbon sequestered in coastal areas" (Ref. 2).