Why the Aravallis come to die in NCR
Among the 23 districts where Aravallis exist, Delhi, Gurugram, and Faridabad are the most urban.
What are the exact boundaries of the Aravalli range? How much of the forests that cover them have been destroyed? Where is this destruction happening the most? These questions have long been part of the story of this old mountain range. The Haryana government’s attempt to open up the Aravallis for development and the Supreme Court order that has stopped it is only the latest episode in this story.
The latest developments in Haryana, however, show that these three questions are interconnected. An HT analysis of satellite data shows that it is easy to cast doubt on the mountain status of what is considered the Aravalli range and the forest status of vegetation existing on it, particularly the parts in the National Capital Region (NCR). This is perhaps why since the 1990s, these forests have suffered the biggest proportional destruction in the NCR part of Aravallis than elsewhere.
So, are there Aravallis in Delhi and Haryana?
The short answer, according to both official and unofficial research, is yes. This, however, does not explain why the answer is being challenged in Haryana by claiming, among other things, that Aravallis do not exist in the state beyond Gurugram. Two maps explain this: the elevation profile and land-cover pattern in north-western India.
The elevation profile shows that the land in Delhi and Haryana, although not flat, is not very high (Map 1). A global map of mountains as they exist now also does not show mountains extending beyond Rajasthan in north-western India. This is because the Aravalli range is about 2 billion years old, around half the earth’s age, and has therefore decreased in height.
On the other hand, deforestation for development had turned the vegetation in this region to shrubs even in 1992, the earliest year for which satellite data has been processed by the European Space Agency’s Climate Change Initiative (ESA-CCI). Using other datasets, researchers have shown that 80% of the Great Aravalli range was covered with vegetation at the beginning of the 20th century, which decreased to 7% by 1998-2001 (Map 2).
Doubts about preserving Aravallis have cost them their vegetation cover
Given the unique position of the Aravallis in NCR, it is clear that the region needs a special legal definition for forests. The Supreme Court order in July 2022, which said that the term “forest” cannot be limited to areas notified as such under the Indian Forest Act, is a step in that direction, as part of the Aravallis are protected by other laws and regulations. However, the Aravallis have already suffered.
How much have the Aravallis suffered? To roughly delineate the range for such calculations, HT used a 2017 report of the Wildlife Institute of India. This report maps the range to 23 districts (Delhi districts counted as one) extending from Delhi to Gujarat. In this region, 213 sq km of natural vegetation (equivalent to a square of side 14.6 km) has been lost between 1992 and 2015. While this is the most direct loss of vegetation, 1,257 sq km (equivalent to a square of size 35.5km) of agricultural land has also been lost. Most of this land is now classified as urban, which has increased by 1,315 sq km since 1992. This makes the land vulnerable to soil erosion and further deforestation (See chart below).
Delhi, Gurugram, Faridabad are the leaders in vegetation loss
Among the 23 districts where Aravallis exist, Delhi, Gurugram, and Faridabad are the most urban. They are also the top three districts in the fractional loss of the 1992 vegetation cover, having destroyed 29%, 17%, and 15% of it. Even in terms of area lost, Delhi (31.4 sq km), Gurgaon (24.5 sq km), and Faridabad (10.9 sq km) rank second, fifth, and eighth among the 23 districts (Plotted over Map 2).
This shows that deforestation in NCR is significant. To zone in on the exact places where most vegetation has been lost in NCR, HT divided the region of the 23 districts into square grids of side 10 kilometres or of area 100 sq km. Except the grids truncated by the boundaries of the region, the 1,736 grids obtained are of the same area. Of these, 491 had no vegetation in either 1992 or 2015. In 999, the vegetation cover did not change, in 17 (mostly in Udaipur) it increased, and in 229 it decreased. Of the 229 deforestation grids, the grid with the highest loss falls in the Lachhmangarh assembly constituency (AC) of Sikar district, the district with the most overall deforestation. However, just as in the case of districts taken in their entirety, grids in the three NCR cities are also deforestation hotspots, occupying six positions among the top 20. Moreover, in the NCR grids, vegetation has been replaced by urban areas unlike cropland replacing vegetation in districts such as Sikar, the Panchmahals, or Nagaur (Map 3).
What does all this mean for the future of the Aravallis?
In sum, the data above shows that the three NCR cities were already very urban in 1992 and, yet, have lost big chunks of forest since then. If they are to remain habitable – deforestation makes a place vulnerable to disasters ranging from floods to toxic air pollution – this process needs to stop, and the lost forest needs to be restored. However, as the grids of most vegetation loss also show, the focus of preserving the Aravallis also needs to expand to places where a large fraction of vegetation still exists and is currently being destroyed.