■ Thar desert expanding fast with land degradation –
✓Recently, the Central University of Rajasthan conducted a study on desertification of the Thar region.
✓The study was undertaken as part of an assessment of the environmentally sensitive areas within the framework of the UN Convention to Combat Desertification (UNCCD).
✓The scientists associated with the project studied the climate and vegetation in Thar to understand the desertification process.
● Key Findings:
✓Focused Areas: It focused on Barmer, Jaisalmer, Bikaner and Jodhpur districts covering more than 50% of the Thar desert.
✓It found that Jodhpur had witnessed a slow speed of desertification.
✓It also found that the vegetation cover and water bodies had increased in the area in the last 46 years and the complex sand region had decreased by 4.98%.
✓Expansion of Thar desert: Along with the gradual destruction of the Aravalli ranges, the Thar desert is expanding fast because of the migration of people, changes in the rainfall pattern, spread of sand dunes and unscientific plantation drives.
✓Impacts: The degradation of land is posing a threat to the desert ecology, while climate change has contributed to the spread of arid regions.
✓The loss of Aravali hills because of unchecked mining activities would result in the sandstorms travelling to NCR and Delhi.
✓The suspended particles from the arid region are contributing to air pollution in NCR.
✓Suggestions: new plans should be evolved for the conservation of the Aravali ranges to stop the desertification towards eastern parts of the State.
● What is Land degradation?
✓Land degradation is temporary or permanent degeneration of productivity of land due to physical, chemical or biological factors.
✓Land degradation is caused by multiple forces, including extreme weather conditions, particularly drought.
✓It is also caused by human activities that pollute or degrade the quality of soils and land utility.
● Present status of India’s Land Degradation:
✓Some 97.85 million hectares (MHA) of India’s total geographical area (TGA) of 328.72 MHA underwent land degradation during 2018-19.
✓Land degradation within dryland regions (arid, semi-arid and dry sub-humid regions) is termed ‘desertification’.
● State Wise breakup:
✓Around 23.79 per cent of the area undergoing desertification/land degradation with respect to TGA of the country was contributed by Rajasthan, Maharashtra, Gujarat, Karnataka, Ladakh, Jharkhand, Odisha, Madhya Pradesh and Telangana.
✓However, land degradation and desertification were declining in Uttar Pradesh, Rajasthan and Telangana in 2018-2019.
● Reasons for Land Degradation:
✓Loss of Fertility by Mismanagement: Due to the use of various scientific inputs like irrigation, fertilisers, pesticides etc. Unscientific cropping practices are also causing harm.
✓This results in problems like soil erosion, loss of natural nutrients, water-logging and salinity and contamination of ground and surface water.
✓Soil Erosion: This is the process by which the topsoil is detached from land and either washed away by water, ice or sea waves or blown away by the wind.
✓Salinity/Alkalinity: This problem occurs in areas of temporary water surplus and high temperatures due to over-irrigation or high rainfall.
✓The salt layer plays havoc with the fertility of topsoil and renders vast stretches of useful land infertile.
✓This problem is particularly serious in areas with assured irrigation in Punjab, Haryana, Uttar Pradesh, western Maharashtra, Bihar and northern Rajasthan (the Indira Gandhi Canal command area). Such lands are known by local names, such as reh, kallar, usar, chopan etc.
✓Waterlogging: This happens when the water table gets saturated for various reasons—over-irrigation, seepage from canals, inadequate drainage etc. The land under waterlogged conditions can be used neither for agriculture nor for human settlements.
