Delhi gasps for air as its green lungs fail
Besides an overall decrease, ecologists are worried that the green landscape of the capital is becoming increasingly fragmented.
- Total Shares
The dwindling green cover of Delhi is often a subject of public debate, given rapid expansion of the urban sprawl and development of large infrastructure projects like the Metro. Yet we find that the city is far more greener compared to other metropolitan cities in India and elsewhere.
The truth is somewhere in between – overall there has been a decrease in the city’s vegetation since 1986, but this decrease is not uniform since the green cover in some areas has also seen improvement. This is what scientists have concluded in a recently published study based on analysis of satellite imagery from 1986, 1999 and 2010.
The core area of the capital – consisting of erstwhile tehsils of old Delhi (Karol Bagh, Paharganj, Sadar Bazar, Daryaganj, Kotwali) and New Delhi (Parliament Street, Connaught Place and Chanakyapuri) – contains higher proportion of green spaces compared to other parts of the city. This is mainly due to the colonial practices of planting of avenue trees in Lutyen’s Delhi and the presence of large parks. In addition, a large part of the Central Ridge forest is also in the city’s core.
However, the core area has registered a decline in the vegetation cover since 1986 due to expansion of built-up area. The greenery in the transition zone – which surrounds the core area – is due to densely vegetated cantonment, other military and educational campuses as well as Northern Ridge and Central Ridge forests. The vegetation cover in this zone grew slightly between 1986 and 1999 and again declined between 1999 and 2010. The third zone, called the periphery, has the least proportion of vegetation cover compared to the two other zones, but the periphery has been experiencing increase in vegetation cover since 1986.
The study now attributes this increase to restrictions imposed on mining activity in the Southern Ridge forest and emergence of small forest patches resulting from afforestation drives. The land use in the Yamuna riverbed too has been changing from agriculture to built area, but agricultural fields have not been counted as vegetation in this study.
“Apart from clearings for infrastructural development and encroachments, the Delhi Ridge – the so-called green lungs of Delhi – are still intact. In fact, the Southern Ridge gained vegetation between the years 1999 and 2010, because of eco-restoration initiative by the Eco Task Force,” pointed out Somajita Paul, who led the study conducted by researchers from the Ashoka Trust for Research in Ecology and the Environment (ATREE) and the Azim Premji University. It has been published in scientific journal Applied Geography. Another green lung of the city is the Asola-Bhatti Wildlife Sanctuary spread out over about an area of 20sqkm. Besides an overall decrease, what worries ecologists is the fact that the green landscape of Delhi is becoming increasingly fragmented.
Connected green spaces are ecologically more important than fragmented green patches, and they help in harbouring biodiversity and offsetting impact of pollution to a great extent. Green cover also helps in noise reduction and acts as a carbon sink.