ISRO-led study analysed satellite imageries of the country over an eight-year period

Nearly 30 per cent per cent of the country’s total geographical area is undergoing degradation, according to a study that analysed satellite imageries of the country over an eight-year period.

The degrading area has increased over 0.5 per cent to 29.3 million hectares during the period, as shown by comparative remote-sensing satellite imageries of the States for the periods 2003-05 and 2011-13. Desertification increased by 1.16 million hectares (m ha) and stood at 82.64 m ha during 2011-13.

There was high desertification and degradation in Delhi, Tripura, Nagaland, Himachal Pradesh and Mizoram, while Odisha, Telangana, Rajasthan and Uttar Pradesh showed some improvement.

The ongoing study, initiated by the Ministry of Environment, Forests & Climate Change, was led by the Indian Space Research Organisation and involved 19 institutes. ISRO’s Space Applications Centre released the findings last month in the form of a ‘Desertification and Land Degradation Atlas’, combining GIS and remote sensing data.

India has committed itself to the U.N. Convention on Combating Desertification that it would fully stop land degradation by 2030. The atlas, adding 68 vulnerable districts, would form part of the country’s action plan to arrest the phenomenon and also be a status report to the U.N. body, ISRO said. The SAC had undertaken a similar study in 2007.

Just nine States together account for nearly 24 per cent of desertification; the other States have less than one per cent of this land. The culprit States in that order are Rajasthan, Maharashtra, Gujarat, Jammu & Kashmir, Karnataka, Jharkhand, Odisha, Madhya Pradesh and Telangana.

Southern State Kerala figures among northern and northeastern States where less than 10 per cent land is degraded. With it are relatively greener States of Assam, Mizoram, Haryana, Bihar, Uttar Pradesh, Punjab and Arunachal Pradesh.

The bad news is that 3.6 million ha of productive land are getting lost, while on the positive side, some land has been reclaimed and the intensity of degradation has been slowed down in a few other areas. “Desertification and land degradation are major threats to agricultural productivity in our country. Combating them is a thrust area identified [by the MoEF&CC],” ISRO said.

The main culprit is water erosion (26 per cent) followed by degrading vegetation (rising slightly nearly nine per cent) and land or soil erosion due to wind.

Rajendra Hegde, head of the National Bureau of Soil Survey and Land Use Planning, Bengaluru, which partnered ISRO in interpreting the data in three southern States, affirmed that even a marginal increase in degraded land is a cause for concern.

“The definition of desertification implies it is degradation that cannot be reversed in a lifetime (around 60 years).”