The desert state of Rajasthan has just gained a huge tract of land — one lakh hectares to be precise. For a state that is known for its arid topography, it is heartening news. An assessment has revealed that Rajasthan is the only state among nine falling within the major arid regions of the country where the degraded land area has registered a decrease over the years.
The assessment is based on maps created using satellite imagery for two different periods, 2011-13 and 2003-05.
The other eight states — Gujarat, Andhra Pradesh, Haryana, Himachal Pradesh, Karnataka, Maharashtra, Punjab and Tamil Nadu — together recorded an increase of 18.72 lakh hectare degraded area in the same period.
The assessment, led by the Central Arid Zone Research Institute (CAZRI), has found that extent of sand dune area is now limited to 48 % in western Rajasthan. Earlier, sand dune area extended to 60% of western Rajasthan.
The maps created under the nationwide mapping project funded by the Union Ministry of Environment, Forest and Climate Change and Indian Space Research Organisation (ISRO) for assessment period 2011-13 found about 29.32% of country’s total Geographical Area (TGA) degraded due to various process of desertification. In 2003-05 this was 28.76%. Thus there has been an overall increase of 1,872,523 hectare degraded compared to 2003-05 when it was 9,45,25,643 hectare.
“Desertification is land degradation in arid, semi-arid and dry sub-humid areas resulting from various factors including climatic variations and human activities, which was adopted in United Nations Conference on Environment and Development (UNCED-1992).” Dr OP Yadav, director, CAZRI said.
“There are several reasons behind Rajasthan registering a decrease in the degraded area. Wind erosion affected area has also reduced by 1.34 lakh hectare. Land use wise, 1.23 lakh hectare under croplands (irrigated and rainfed) is now free of wind erosion hazards compared to 2003-05 assessment,” Yadav said.
“In Rajasthan, only degradation due to mining, water erosion and vegetation has increased,” Dr PC Moharana, principal scientist, said, adding that much of the improvement in desertification scenario of the region has been achieved due to combined efforts. Controlling wind erosion and sand spread was a priority activity as it was the single largest environment problem of this region
CAZRI at Jodhpur is engaged in assessment and mapping of desertification status of arid areas in India since the preparation for the first United Nations Conference on Desertification (UNCOD) at Kenya in 1977. Studies have been carried out by CAZRI to understand the problem, its severity and its spatial distribution. The first database on desertification was prepared by CAZRI in 1990 for western Rajasthan which showed that wind erosion of moderate to severe intensity affected 50 % area, water erosion affected 9% area, and waterlogging and salinity affected 2% area. Around 62 % area of western Rajasthan was assessed as being moderate to severely degraded, 31 % as slightly affected by various processes and rest 7 % area was free from degradation.