By Dr Amal Kar and Prasad
The author is Principal Scientist and Head of Division of Natural Resources & Environment, Central Arid Zone Research Institute (CAZRI), Jodhpur
The vulnerability of drylands is now markedly visible with acres of cropped land degraded. The 1977 Landsat MSS image, shows Ghaggar Diversion Channel bringing excess water of Ganga Canal to the interdune plains. The fertile valley of the Drishadvati palaeo channel, with crop lands depicted in blue, covering about half the image can be seen. The 2000 Landsat ETM image shows the same area where the Drishadvati palaeochannel is full of water that seeped out of the flooded interdunes. Milky white tone is indicative of the salinity developed due to waterlogging while red, indicates cropped lands, which show a steep decline from the previous image.
Land degradation is one of the most potential environmental threats for any nation, more so where the livelihood of people depends largely on agriculture and related land based activities. Although land degradation is common to all climatic zones of the world, its occurrence in the arid, semi arid and dry sub humid zones - the drylands, is of more concern because of the low production potentials of the land in these zones vis-à-vis high human and animal population pressures that...