Tall brick and reinforced concrete structures, a dense-packed population, and intense industrial and human activities are the hallmarks of a city. Although cities account for only about 2% of the world's land area, they are the primary emitters of waste and pollution and contribute about 70% of the world's greenhouse gas emissions.
Vegetative green spaces and blue water bodies that could absorb harmful gases and pollutants or give people a sense of nature are also scarce in the cities. Unsurprisingly, city residents experience higher air temperatures, inhale more polluted air, and feel less connected to nature than the countryside residents. Exacerbating the issue, the climate is worsening and the city's green spaces are shrinking, making the overall city environment harsher for city residents day by day.
The dwindling quality of cities' environment is a global phenomenon, and Bangladeshi cities are no exception. In fact, Dhaka's performance in the recently released cities' Global Liveability Index 2023 is abysmal. Dhaka ranked 166 among the 173 evaluated cities. Dhaka also consistently ranked high in terms of the most polluted cities in the world. Added to the concern, recent research has found about 66% reduction in green spaces and about 33.7% reduction in blue areas (water bodies) in Dhaka North over the past decade.
The situation is likely indifferent to other parts of the city. Numerous media reports consistently highlight Dhaka's shrinking of green and blue spaces due to tree cutting or filling up of water bodies. All these reports point toward an overall deterioration in the city's nature.
Major policies
When the question of improving the statute of any city's natural environment arises, four major policies come to the forefront: (1) Shifting from high to low-carbon pathways, (2) reducing harmful pollutants in city activities, (3) streamlining the circular economy, and (4) integrating blue-green infrastructure in the city and urban planning. Some require technological innovation and significant financial investments, while others require proper planning and public commitments. For instance, integrating blue-green infrastructure in the city and urban planning requires minimum technological innovation and financial investment, making the policy germane for a country like Bangladesh.
Rightly so, Prime Minister Sheikh Hasina has emphasized city greening and the protection of water bodies in the nation's futuristic progress agenda. However, the adequate application of the policy remains far from satisfactory. In many instances, city modernization efforts come at odds with city green and blue spaces. In addition, mostprograms designed to improve the city's nature are implemented by government agencies with little to no involvement of city residents. This is surprising because the importance of community involvement in nature conservation for climate adaptation is well acknowledged within and beyond Bangladesh.
The differential disciplinary focus could be a reason for the use versus no use of a community-based approach in the countryside versus the city's nature management. City development planning, including its nature improvement planning, is considered the domain of engineering, urban planning, and architecture. By contrast, nature conservation or climate adaptation is regarded as the domain of natural resources management. While natural resources practitioners think about the usefulness of community involvement, practitioners from other disciplines seldom think that way.
However, as our emphasis on city greening increases, the traditional disciplinary boundary for city development versus nature conservation is becoming increasingly blurred. In such a situation, city planners, engineers, architects, and natural resources managers must cooperate and adopt an innovative and interdisciplinary approach to tackle the problem.
What to do
To start, one can think of adopting gardening ideas, promoting residents' participation in city greening, and creating favourable conditions for city residents to come forward and join the effort. Let me clarify how that can be done.
First, city residents can practice balcony or rooftop gardening in office and residential buildings. Second, they can practice habitat gardening in residential and office complexes and educational institutes. Third, they can extend their hands in establishing dedicated sections of habitat gardens within our existing parks.
The idea of a balcony or rooftop gardening is relatively well-known. And it is praiseworthy that the government is considering a significant reduction in household tax to popularize rooftop gardening among city residents. However, Dhaka has several thousand government and non-governmental office buildings.
Other cities also have a substantial number of offices. Extending a balcony or rooftop gardening to those office buildings will substantially improve the city's nature. It will also be a great motivation for the city residents to see that the concerned authorities are not only professing to practice rooftop gardening for others, but the leaders themselves are also practicing it.
Habitat gardening could be another promising avenue for improving the city's nature. To be clear, habitat gardens are small green spaces or pocket parks of regular or irregular shape that could offer recreational areas for humans and safe habitats for plants and animals. The main difference between tree planting versus habitat gardening is that the former usually focus on one layer of trees. In contrast, habitat gardening focuses on tree and non-tree vegetation, which can form diversified layers, generating favourable conditions for fascinating wildlife such as butterflies, birds, and frogs. This offers a sense of wilderness and adds charm to city life.
Individuals can raise habitat gardens on their own or community properties. Many residential complexes or housing societies often allocate some spaces for amenities. Those spaces can be ideal for community gardening. The same gardening concept can be applied to available areas in educational institutes like schools, colleges, madrasas, universities, or even office compounds. City authorities can also consider allocating a dedicated habitat garden section within our existing parks or other suitable but unutilized areas.
That being said, the recent dengue spread in the cities could discourage gardening. However, one can choose the right species and implement proper garden management to minimize the problem. For example, one can include plants with strong odours, such as lemongrass, basil, marigold, catnip, garlic, or rosemary, that are known to be mosquito repellents, in their habitat or rooftop garden and keep the garden clean, thereby potentially minimizing dengue spread.
Nevertheless, the usefulness of habitat gardens in saving biodiversity, combating climate change, enhancing social bonding, and, most importantly, improving the liveability and lovability of cities has been showcased in numerous cities worldwide, including Shanghai and Singapore. The city authorities in Bangladesh can draw from those experiences and collaborate with the Bangladesh Forest Department, which has proven efficiency in social forestry, to promote community-based habitat gardening in the cities.
City residents always look for a lush green, blue waterfront and clear sky to feel a sense of satisfaction and happiness. Although parks, green spaces, or lakes could provide a sense of naturalness in the city, their numbers are limited,and their quality is dwindling. Given the space constraint, city authorities can do little to increase the number of parks or green spaces.
However, our city authorities can pay attention to involving city residents or encouraging their contributions to city greening or waterbody protection activities. Residents also need to come forward and join hands with the government to improve the livability and lovability of their cities and feel a sense of belonging to the town they live in. Above all, we want to develop our country sustainably and make our Bangladeshi cities beautiful places to live and prosper.
Shekhar R Biswas is a professor of Ecology at East China Normal University in Shanghai.