Fact Box: Shrinking of Cauvery Delta Region
It is due to anthropogenic factors such as diversion of land for non-agricultural purposes and factors like climate change.
As per the study undertaken by S. Janakarajan, retired professor of the Madras Institute of Development Studies (MIDS), Cauvery delta region has shrunk and the cultivable lands are increasingly deteriorating into waste lands.
• The researchers tracked land use and changes to land cover to show that the delta region has shrunk by 20 per cent.
• It is due to anthropogenic factors such as diversion of land for non-agricultural purposes and factors like climate change.
• The drastic decline in crop cover and a 13-fold increase in wastelands between 1971 and 2014 indicate a worrisome phenomenon.
• There is 14 times increase in the mangrove cover since 1971 in the region.
• Due to sea water access, there has been a significant rise in shrimp farming along the coast, which is unfavourable for agricultural practice.
• With 72 per cent of the low-lying land in the State falling under the delta region, the land is at greater risk of submergence as a result of rising sea levels.
• The Cauvery delta has also witnessed a decline of 80 per cent in sediment deposit over the last century.
• A noticeable result of climate change has been the cycle of drought and flood that the coastal areas have been enduring.
• There has been a decline in the overall rainfall between 1974 and 2004, however, the delta districts received 1200 mm of rainfall, which is high.
• Periodic storms in the delta region exerted additional stress on the 14 regulators in the canals at Nagapattinam district, that help divert drainage water flowing from the Cauvery river system.
• Another major vulnerability is the soil type. The delta region has clay soil, of which 52 per cent is cracking clay, which is very much at risk if it doesn’t receive continuous irrigation.
• There is a decline of dairy as a secondary occupation in the delta districts, with the cattle population also registering a steep decline.