3 desert patches found in Ganga basin

Unusual occurrences

Scientists have found the formation of three tiny pockets of deserts in the river-rich Gangetic basin by using satellite images.

These arid zone patches are in western part of the Great Indian desert (Rajasthan), northern Aravalli range (western Madhya Pradesh-eastern Rajasthan) and western Chota Nagpur plateau (Jharkhand and bordering areas of Odisha).

While the first zone is located on the fringe of the Thar desert region, aridity has increased in the other two pockets more recently due to urbanisation.

As many as 36 districts in these areas are becoming drier and drier over the last three and half decades, triggering concerns among scientists.

The alert comes from researchers at the Indian Institute of Technology Kharagpur, who extensively studied the 1975 satellite images of the Ganga river basin and compared them with space-based imageries from 2010.

“Our analysis clearly elucidated the emergence of 3-pockets of the alarming increase in aridity that could cause other cascading impacts in future, including encroachment of more lands under ‘desert’, making them nearly unfit for human use,” said Shafique Matin, who carried out the aridity anomaly study as a part of his doctoral thesis.

There are several signatures of increased aridity. One of the first sign is a visible change in the vegetation landscape.

In 1975, forests of dhok tree (Anogeissus pendula) was commonplace in Japiur and surrounding areas whereas in 2010, only a few sparsely distributed A. pendula trees were around.

“Another species named Prosopis juliflora (Indian name: Junglee kikar or Vilayati babool) that can survives even with increasing aridity is now replacing the endemic flora in high aridity zone. The cascading effect of such aridity is high,” Matin, who now works for the Irish government told DH from Dublin.

Overexploitation of natural resources for farming and expansion of opencast mining are the causes of desertification in other two pockets in the 844,000 sq km Ganga river basin. Changing rainfall pattern adds to the woes.

Matin and his colleague M D Behera published the results of their study in the latest edition of the journal Current Science.

Increased desertification threat is one of the ecological threats the world is facing along with climate change and loss of biodiversity.