Grass

Touted as a long-term solution to flooding of Mandaue City, establishment of a mangrove eco-park has begun, having received funding from the Department of Budget and Management (DBM) (Ref. 1). Through establishment of mangroves, the eco-park will "perform a significant role in shoreline protection, acting as a buffer against strong winds and waves", which is considered particularly important in light of the anticipated effects of climate change (Ref. 6).

A total 17-hectare plot is to be rehabilitated, as identified in the Mandaue City Government's Comprehensive Land Use Plan (Ref. 3). At present, it is unclear whether nature-based solutions (including mangrove restoration) are to be implemented across the entire 17ha of the site, but initial efforts have been focused on the restoration of a 5-ha section of mangrove forest (Ref. 2). Due to the lack of data on how exactly the remainder of the 17-ha area will be restored, the total NBS area for this project has only been recorded as 5-ha (5000m2) within this case study, rather than the entire 17,000m2 which is encompassed within the site.

The site is situated at the outfall of the Butuanon River which frequently overtops as a result of heavy rain and has been considered "biologically dead" since 1992 (Ref. 7). The site itself comprises a former dumpsite which had been "left derelict and filled with piles of trash", hence in addition to reducing flood risk, its rehabilitation will serve as green space in which "the residents of Mandaue City [can] gather and enjoy a breath of fresh air" (Ref. 2). The eco-park is considered to bring the added benefit of filtering water as it enters the Mactan Channel, in addition to reducing greenhouse gas emissions through carbon dioxide absorption (Refs. 1 & 6).

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 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 Wuqing District of Tianjin is a rapidly developing suburban district, northwest of the city core, containing 4 larger 5 smaller rivers, 5 water reservoirs, Wetland area that partially protected by the DaHuangPu Nature Reserve, the Jinbei Forest Park, several public parks, greenery near buildings, green roofs and vegetation along roads. A spike in population growth going from 130.000 in 2000 to 1.2 million in 2018 brought the need for wide urban development where the district focused on implementing blue and green infrastructures (1). "The urbanized area of the district is reported to meet the requirements of the national ‘Garden City’ standard with over 36% green coverage, currently aiming to achieve 45% on the long run, and was selected as a pilot national ecological demonstration area for green urban development in 2014. Since 2014, over 500 million EUR was invested into blue and green infrastructure projects (1 p26). The three flagship projects evaluated here are 1) the South Lake (Nanhu) Area that combines business, recreational, residential, and ecological development around in a waterside area, 2) the North Canal Suburban Park which is a recreational, entertainment and wetland area on 2.53 km2 where over 72.000 trees were planted in recent years, 3) and the 400 meter wide, multi-functional green corridor running along the Cuiheng Road (1).

Since 2008, the City of Portland, Oregon has used various policies and programming to encourage the use of eco-roofs (vegetated roofs) throughout the city to address stormwater management (Ref. 2,3,4). In addition to stormwater management, eco-roofs have the benefits of: saving energy, reducing pollution and erosion in waterways, preserving fish habitats, creating new habitats for birds and insects, absorbing carbon dioxide, cooling urban heat islands, filtering air pollutants, and providing urban green space (Ref. 1,5). From 2008 to 2012, the City of Portland used the Ecoroof Incentive program to encourage property owners and developers to construct ecoroofs (Ref. 4,5,12). In 2018, the City of Portland adopted a mandate for ecoroofs in new buildings (Ref. 2,3,12). These policies and programs led to a growing interest in the use of ecoroofs, and resulted in the construction of over 130 ecoroofs (Ref. 3,4,11).

The Tagabe Riparian Corridor Regeneration Project is an integrated catchment project ‘designed to build resilience into the riparian system to safeguard human wellbeing in the face of current and future climate change challenges and key population/ resources demands’ (Ref. 4). The project is focused on the ‘riparian margins of mid to lower catchment streams in the Tagabe catchment’ (Ref. 4,5). Activities consist of ‘riparian revegetation and stream bank protection; sustainable land management of adjacent farmlands; and point source pollution prevention and remediation’ through a series of 5-year management periods (Ref. 4,5). The project was part of the larger PEBACC (Pacific Ecosystem-based Adaptation to Climate Change) project and is now supported by the Vanuatu Government and various other initiatives like the Pacific R2R – Ridge to Reef programme (Ref. 8,9).

Thammasat Urban Rooftop Farm (TURF) is Asia's largest organic rooftop farm, which unites principles of modern landscape design with traditional agriculture of rice terraces, to transform wasted space into productive land. By mimicking traditional rice terraces, Thammasat University Urban Farming Green Roof has become an all-in-one solution–as a public green space, urban organic food source, water management system, energy house, and outdoor classroom–which serves as an adaptation model for anticipated climate impacts that can be implemented and developed across Thailand and Southeast Asia. Additionally, the mountain-shaped Thammasat University Green Roof utilizes its vast space as an infinite source of clean energy, not only in terms of organic food but also solar power for the community. [1, 2, 3]

The Sino-Singapore Tianjin Eco-City (SSTEC) is a bilateral project between Singapore and China with a large scale private-sector involvement with the objective to "transform the 34 km2 barren, non-arable land and polluted wastewater ponds into ... a thriving city which is socially harmonious, environmentally-friendly and resource-efficient – a model for sustainable development for 350 000 residents. (1,2). The Eco-Valley is an S-shaped, 11 km green spine that runs through the whole Eco-City connecting its centre with sub-centres, all four residential districts, community spaces, multiple parks, commercial zones, and waterside areas as a scenic park providing a place for connectivity, transit, leisure and recreation for residents (1).

The Cheonggyecheon Stream Restoration Project saw the dismantling and removal of an elevated freeway and the uncovering of a 5.84km section of the Cheonggyecheon historic stream in the centre of Seoul, South Korea (Ref. 2). One of the world’s largest and most densely populated cities, the revitalisation of the Cheonggyecheon Stream has provided Seoul with an ecologically sensitive green pedestrian corridor in an area that was previously recognised as being congested, overpopulated and polluted (Ref. 4). The restoration has provided environmental, social and economic benefits within its immediate proximity (Ref. 2). In addition to becoming a "vehicle for revitalisation, urban renewal and economic development", it has "also signified a shift in Korean planning priorities", with both city authorities and residents now placing an emphasis "on health, sustainability and social responsibility" (Ref. 4). It has further "become a template for planning intention and action across South Korea" (Ref. 4).

The wetlands to the east of Kolkata are well known over the world for their multiple uses. The locals are using the naturally occurring wetlands for wastewater fisheries and vegetable farming on garbage substrate & effluent irrigated paddy cultivation. In the process, the wetlands treat the wastewater and have saved the city of Calcutta from constructing and maintaining a wastewater treatment plant. Currently, encroachment has deteriorated the wetland ecosystem significantly. This intervention is about the management of the degraded wetland to recover it the best way possible. The goal of management planning is to „maintain East Kolkata Wetlands in a healthy condition to enable the delivery of its full range of ecosystem services and sustain biological diversity values’. [1, 2, 3]