Urban biodiversity: We can all do our bit to save it

For all the environmental degradation that Bangalore is made to endure, the city still has considerable biodiversity left to talk about. Here, it is easy to miss the forest for the trees. The biodiversity is there, breathing right under our noses, not exactly teeming as it might have been till even a few decades ago, but it’s there.

Biodiversity is a subject that rarely finds itself making it to the headlines. In fact, the International Day for Biological Diversity just went by (on May 22). How much of the subject did one see in the newspapers, or on television? Not much, one would guess. Even less talked about, though more critical for those living in cities, is the issue of urban biodiversity.

Although cities occupy just 2 per cent of the Earth’s surface, their inhabitants use 75 per cent of the planet’s natural resources. The United Nations Environment Programme (UNEP) summarises the issue thus: “Cities draw on their surrounding ecosystems for goods and services, and their products and emissions can affect regional and even global ecosystems. Healthy ecosystems and biological diversity are vital for cities to function properly. Ecosystems provide three main kinds of services to the city: provisioning of food, fiber and fuels; regulating through purification, detoxification and mitigation of droughts and floods; and enriching the spiritual, aesthetic and social life of urban dwellers.”

Among those in India looking at the issue of ‘cities and biodiversity’ is Harini Nagendra, now with the School of Development at Azim Premji University. In 2013, Nagendra and two fellow researchers released the findings of a study that assessed the abundance, diversity and distribution of insects in urban domestic gardens in the tropics, through a study in the rapidly expanding Indian city of Bangalore.

They studied 50 domestic gardens and recorded a large number of insects: 2,185 insects from 10 orders, of which ants, bugs, beetles and flies were the most common. They found 25 species of trees (from 160 individuals) and 117 species of herbs and shrubs in the 50 sampled domestic gardens. The number of insect orders encountered was significantly related to the number of tree and herb/shrub species.

In 2014, Nagendra and a colleague found that half of the tree population in the city’s slums had medicinal properties. They found a total of 553 trees of 46 species in 44 slums, which were shortlisted from 114 slums identified within the city limits. Besides, 95 species of herbs, shrubs and creepers were seen to be grown by inhabitants. The vegetation in the slum areas was rich in diversity.

Nagendra has been working on biodiversity issues in cities for a while now. How much concerned, does she think, are urban citizens about biodiversity issues? “I find it ranges widely. Many urban citizens are extremely concerned, and have worked diligently, braving everyday challenges of time, and difficulties such as threats, to protect places in danger. Others at the end of the spectrum are fond of biodiversity, but may not be doing much about it. The main challenge is to convert the latter into the former.”

And how much concerned is she herself? Nagendra replies, “I am very concerned, of course: being from Bangalore, having imbibed a fondness for biodiversity from my mother and aunts, and being worried about what kind of a city we will leave behind for my daughter’s generation. So, my concerns are shaped by my experiences as a researcher and a citizen, but perhaps most as a mother, looking at children in the city today, who hardly get any exposure to biodiversity or nature.”

How worried should citizens be about depleting green cover in cities, which are now de facto concrete jungles? And, if biodiversity disappears altogether, what would it mean for the ordinary citizen? Nagendra responds, “Green cover in cities is essential for urban sustainability. I have heard some people (including administrators) say that we need trees, but not in the city, or not in public places like on roads. This is extremely short-sighted. Trees play environmental, social, and ecological roles that are fundamental to our daily lives. In terms of environmental services, they clean the city’s polluted air, generate fresh oxygen, help rainfall to percolate and recharge into the ground; in terms of the social, they act as places for congregation, socializing, for children to play, for street vendors and their customers to engage with each other under the shade, and for worship of nature; and in terms of the ecological, of course, you can’t have birds, insects and urban wildlife without plants and trees!

“But in addition to all of these, there is a very important daily use value of urban green cover which is getting increasingly removed from public discourse. Green spaces are provide cattle feed; fuel wood; fruits; green leaves; seeds used to make oil; and so many other livelihood, energy and nutritional sources for the city’s poor. If biodiversity disappears altogether, it affects the millions of ordinary citizens, who depend on trees for all of these uses, reducing their food security, increasing their dependence on the market, and impacting their health.”

Given this backdrop, it is ironical that city planning does little else apart from keeping some token space set aside for parks. Why is biodiversity, as a whole, not incorporated into policymaking? Says Nagendra, “We have no tree policy in Bangalore, for instance. No city-level guidelines about what species to plant, in what conditions. We are replacing majestic trees that shaded a half acre in size by small royal palms and conifers, without considering issues of what ecological and environmental services are provided by different species. Trees on the streets are seemingly not a concern for the city, and neither are trees in home gardens, or in poorer parts of the city such as slums. The entire national focus on cities has shifted to the smart city: well, smart need not only mean technology, a green city is the smartest city I can think of! It would be low-cost, adaptive, and resilient to a whole host of environmental challenges from pollution to climate change! Perhaps there is not enough money in biodiversity… or perhaps it does not seem glamorous enough for policy makers enamoured of quick fix massive technological solutions.”

So, what does the individual do for urban conservation? “In a city where even a 91-year-old homemaker with 10 children has played a role in conserving a park (Honnamma Govindayya in Jayanagar), anyone can do their bit,” Nagendra concludes. She has a point there.