Rehabilitate and restore damaged or destroyed ecosystems

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].

The Ningbo Ecological Corridor is a post-industrial landscape ecological reconstruction project. It is located in the middle of the Eastern New Town in Ningbo, with a total area of 90 hectares [4]. Built upon a typical post-industrial site with degraded ecologies that needs to be healed and would soon become part of a new urbanized district, this project is holistic ecosystem services-oriented, introducing terraced wetland to manage elevation change of the site to slow the flows of urban runoffs from the street down to the river and remove the nutrients [1]. “Before being designed, the site and surrounding areas were fragmented farmland, villages and factories that were planned to be relocated - a typical brownfield in the rural-urban fringe of the southern region of China”[1]. With the implementation of the project, "the original channelized river is transformed into a meandering eco-friendly waterway dotted with tree isles to increase the interface between organisms and water bodies to empower the river’s purification capacity. The project uses productive crops and annual flowers that are rotated to bring seasonal surprise and agricultural vitality to the growing city. Boardwalks are designed to allow visitors to have intimate experience of nature and the nostalgic pastoral landscape. Pavilions made of corten steel floats on wetlands and terraces, giving the ecological corridor a touch of contemporary urban life and art. [1] "As a result, this project demonstrated landscape as an ecological infrastructure that heals the degraded ecological system meanwhile provides social and cultural services to the establishing communities." [1]

St Inez creek was an ecologically functional tidal waterbody in Panaji, Goa. Panaji has been identified as one of the most vulnerable coastal cities from floods due to the predicted sea-level rise. St Inez creek is one of the very important freshwater bodies in the city because of its cultural, social and biodiversity value. Recently, the ecological functionality of the creek was severely compromised through a combination of natural degradation and anthropogenic influences, which includes sedimentation, collapsed embankments, eutrophication, weed growth, pollution, the release of raw sewerage from neighbouring informal settlements and dumping of construction debris. The current intervention is about the restoration of the creek to conserve the urban nature and ecological systems and to increase the resilience of the city. [1, 2]

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)

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)

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)

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)

A multi-purpose green belt (12 km in length of Batticaloa Municipal Corporation coast) was established to protect the lagoon and coastal areas, restore mangrove ecosystems and improve coastal biodiversity. The project comes under activity 1.3 of the overarching project Climate Resilient Action Plans for Coastal Urban Areas in Sri Lanka (CCSL). The project focuses on the most urgent and immediate needs of the Sri Lankan coastal cities in adapting to climate change, and mitigating risks and the severity of impacts through Disaster Risk Management (DRM). The green belt plantation was done with Casuarinas plantation in 400 ha (out of which 75% by Mandru and 25% by the Forest Department), mangrove forest redesigning and protection of the existing vegetation. [1, 2, 6]

The Gangxia 1980 green roof, a pilot of the Green Cloud project, was launched by The Nature Conservancy (TNC) in collaboration with key partners, including: Zhubo-AAO; Glocal Estate Management; and Urban Planning & Design Institute of Shenzhen (UPDIS) [1]. Located on an old building in Gangxia village in Shenzhen, the project utilizes three-dimensional light steel structures that are simple to construct and have the capacity to hold over 420 plant containers, filled with plants mostly native to Southern China [1, 2]. The original concrete rooftop is transformed by vegetation, which is capable of absorbing and preserving rainwater, creating a nature-based stormwater management system for the residential building, achieving a 65% of run-off control rate [1, 2]. As a result, a living “green cloud” is formed on a rooftop of Gangxia village, showcasing “a model to improve the urban village’s stormwater management system and its living environment” [1. p.33].