Earmarked public budget

The extensive Rain Garden Project underneath the Begumpet flyover was carried out in Hyderabad City of Telangana State in India as a beautification project, creating a wetland system banked by lush vegetation (1,2, 4). The Hyderabad Metropolitan Development Authority (HMDA) developed this project to restore, conserve and regenerate the environment of stormwater drains (locally named as open 'Nalas') (1,2,3,6). This project is located at the intersection of Kukatpally Nala and Yousufguda Nala and stretches over 2 hectares and runs for 400 meters (1,2). The project was created for a more natural flow of stormwater to allow it to soak into the ground as well as reduce mosquito breeding on Nala (1,2). It was completed in 2018, creating a positive impact, through which the Hyderabad Metropolitan Development Authority (HMDA) further decided to develop more such projects in other parts of the city (4). Hyderabad City was also awarded for this project under the green and clean city category - Smart Cities India (SCI) Awards (5).

Revitalizing Informal Settlements and their Environments (RISE) is one of the pilot projects carried out in the Batua neighbourhood (1.9 km2 area) of Makassar City (119 km2 area), province of South Sulawesi in Indonesia, which was commenced in 2017 and concluded in 2022 (1,2,3). Batua neighbourhood (six settlements of around 1,600 people) was the first demonstration site for this project which was completed in 2019 (3,4,5). The main challenge was that many households who lived in informal settlements lacked access to centralized urban infrastructure and faced threats from climate change (3,4). The project was proposed to reduce the impact of climate change on marginalized communities in Makassar by providing localized, water-sensitive interventions that addressed issues related to sanitation and water management (1,2,3,4). The introduction of water-sensitive solutions enabled targeted communities to recycle wastewater and rainwater, restore natural waterways, improve water quality, and reduce vulnerability to flooding (3,4). The RISE program initiative integrated nature-based solutions like wetland restoration, bio-filtration gardens (the process of using beneficial bacteria to clean water on a molecular level to remove contaminants), stormwater harvesting, filtration paths and new sanitation structures to improve wastewater management and diversify water resources through community-driven development (1,2,3,4).

Kempegowda International Airport Bengaluru (KIAB)'s new terminal 2 is an environmentally friendly initiative that uses innovative methods to maintain ecological sustainability using native plants (Ref 1, 2). The terminal was built on four guiding principles: technology leadership, being a terminal within a garden, environmental and ecological stewardship, and a celebration of Karnataka’s rich heritage and culture. Through the "terminal within a garden" project, the aim was to create a calming and relaxing space for passengers using greenery for visual appeal as people pass through the airport (Ref 1). Hanging gardens, trees, and green walls are the primary nature-related features included in the terminal and an outdoor greenbelt around the terminal. The airport uses native plant species, including trees, flowering plants, and shrubs (Ref. 2).
The terminal area also includes water bodies, cascades, and miniature waterfalls to maintain the natural atmosphere. The terminal also has extensive rainwater harvesting and groundwater recharge facilities (Ref 1). Other sustainable goals in the terminal area include energy saving, water conservation, waste management, and pollution control measures (Ref 2).

The Rajakori lake rejuvenation project aimed at reviving an existing lake using a natural and sustainable treatment system, the "Scientific Wetland with Active Biodigester (SWAB)". SWAB technology uses a two-step process involving (i) a sedimentation tank equipped with a biodigester and (ii) a constructed wetland system. The untreated sewage waste is passed through this two-step process that uses microbes and plants to reduce pollutant levels. The project also involved redeveloping the public space around the lake for community use (Ref 1,2). Before 2017, the lake was overfilled with sewage and waste from nearby neighbourhoods due to a lack of proper sewage management. Initiated by the Delhi Government, the project aimed at using low-cost natural methods rather than conventional techniques involving concretized bases and chemicals to treat water (Ref 1, 4). Due to its success and cost-effectiveness, this project now serves as an excellent example for other projects within Delhi (Ref 5).

In 2017, the city of Jakarta initiated a peri-urban farming program under its Urban Agriculture Program that aimed to achieve sustainable agricultural production, rural economic sustainability and long-term environmental sustainability (1,4).
South Jakarta is one of the five administrative units that form Jakarta is a prosperous city with more than 2.2 mils. inhabitants. Industrial production as well as urbanization developed quickly in the city, leading to a steep increase in population. Meanwhile, the city experiences a reduction in agricultural land converted into settlements and industrial land, as well as soil deterioration. The city needs agricultural land for production and to establish food security. Furthermore, it needs to improve air pollution as well as oxygen provisioning. As such a solution had to be found (1).
To implement the program a total of 12 communities in the South Kebayoran Lama subdistrict of South Jakarta participated in implementing and operating urban farms. One of these communities has been the Kebayoran Lama Selatan Urban Village managed by Seruni Indah Farmers Group (Kelompok Tani Seruni Indah) which is a very successful example of sustainable organic urban farming supporting more than 3500 residents. The engagement consisted in using vacant and private yard land for horticultural crops (vegetables, fruits and ornamental plants), spices, medicines, herbs etc. through hydroponic and conventional practices that could benefit the community and the general public. 15 gardens have been implemented with funding provided by the Indonesian government (3, 7).

In 2005, a constructed wetland was established in Barangay Villareal, Bayawan City in order to improve a peri-urban settlement and promote domestic wastewater treatment with reed beds. The wetland covers an area of 2680 square metres and comprises two reed beds, with the first bed utilizing perforated pipes beneath a sand and gravel substrate for vertical flow filtering, and the second bed utilizing horizontal flow for biological filtering. The roots of the Phragmites karka reeds, which are used in the system, act as a natural filter, removing microorganisms and pollutants. The treated effluent is reused for various purposes, such as watering plants, firefighting, and irrigating ornamental plants and agricultural crops. The overarching objective of the initiative is to safeguard coastal waters from pollution caused by domestic wastewater and enhance residents' quality of life by providing safe sanitation and wastewater treatment facilities. Furthermore, the initiative seeks to showcase the effectiveness of constructed wetlands, encourage the use of locally available reeds for wastewater treatment, and conserve water and nutrients by reusing treated wastewater. [1,2].

The National Garden Park is the largest park in Ulaanbaatar and the only park of its kind in the capital city of Mongolia, offering multiple environmental services, recreational and commercial functions. Currently, the park extends to 183 hectares, covering 23% of the total green construction in the city, and stretches from the northeastern part of the Marshall Bridge to the Uliastai Bridge in the Bayanzurkh district. In the long term, the park is planned to be extended to have a total area of 973 and to have 1.200.000 trees planted within the “One Million to One Billion” afforestation program. The park offers a range of recreational facilities and services for citizens, including bicycle and pedestrian areas, specialized sports areas and children's playgrounds. It also houses trade and service organizations. As a result, the park has become a popular recreational area for the citizens of the capital and is the most visited urban park in Ulaanbaatar. During the summer, it attracts an estimated 12-15 thousand visitors a day, and during the winter, it sees 6-9 thousand visitors a day. The National Garden park was officially established in 2009 with the aim of protecting the Tuul River Basin's drinking water source, reducing air pollution, and increasing green space to create a healthy eco-environment and providing recreational opportunities for the public. In 2016, the National Garden Park was designated as a local property budgetary enterprise with defined primary functions, management structure, control, and rights under the administration of the Assembly of Citizens' Representatives. The park currently employs 113 staff members (as of 2021). (Ref. 1. and 4)

Raipur city is known as the seventh-most polluted city in the world (2, 3, 4). In response to the escalating problem of air pollution and its public health effects, the state of Chhattisgarh in India has envisioned the creation of a verdant and healthy natural space for urban inhabitants in the heart of Raipur - the Oxi-zone (3).This project acts as the 'Breathing lungs for Raipur' (1, 2). Approximately 19 acres of land were allocated to create an ‘oxy-zone’, including the demolition of buildings to plant trees in their place (1, 2, 4). Inspired by the iconic Central Park of New York City, and suggested by a local citizen group, the Oxi-zone aims to transform this area into a thriving habitat for diverse species of trees and plants, which will also provide water bodies to replenish the groundwater in the vicinity (2, 3, 4). In summary, this project is an integrated green space, enabling residents to relax, meditate and exercise within the “shadow of nature” (3, 4).

This project is Kerala's first Miyawaki model urban forest developed on the premises of Kanakakkunnu Palace of Trivandrum city (1, 2). The project was initiated by the Kerala Tourism department and implemented with the help of Nature’s Green Guardian Foundation and Invis Multimedia (which also sponsored the initiative) (3). A multi-layered forest creation is targeted through the Miyawaki method, a method developed by Dr Akira Miyawaki, a Japanese botanist. The method involves growing native plant species in close proximity to each other (3). Such urban forests are planted with the objective of creating a self-sustaining ecosystem that helps in a greater quantity of carbon dioxide absorption and purification of air (1). The project provides a wilderness experience to urban dwellers who frequent this tourism hot spot for relaxation and recreation (1, 3). After the success of this first forest project in Trivandrum, Kerala, in 2020 the Kerala Tourism launched a project to create more Miyawaki micro forests at 22 tourism spots in 12 districts across the state (Ref. 5).

The project focuses on creating communal vegetable gardens in different barangays (small territorial and administrative districts forming the most local level of government) in Iloilo City. As part of the Plant Plant Plant Program of the Department of Agriculture, the project was initially implemented in 12 districts in the city, to provide jobs, and nutritious food and increase public awareness about food production and security amidst the Covid-19 pandemic in 2020. Since then, the project has expanded to 44 more districts, and the city has also issued a regulation to institutionalize urban gardening activities in the city. The communal gardens are expected not only to serve as a source of food but also as a source of livelihood to combat the threat of hunger and poverty. Apart from vegetable gardens, the city also looks into introducing integrated farming in which districts can also plant fruit-bearing trees and raise chickens and tilapia and also provides a series of seminars to empower district residents to produce and sell their food. Currently, around 300 hectares in the city are planted with rice and vegetables [1,2,3]