New Delhi: The rapid decline of groundwater levels around the world is a huge cause of concern.
A comprehensive research, which spanned over four decades and included data from more than 1,70,000 wells across 40 countries, pointed to unsustainable irrigation practices and worsening effects of climate change as primary culprits behind this scary trend.
India is among around 40 countries where the situation is serious. Some areas in Indo-Gangetic basin have already passed groundwater depletion tipping point, according to the study published in the Nature journal.
Severe depletion of groundwater — which is a critical source of freshwater for agriculture, households and industries — could potentially lead to dire economic and environmental consequences.
Among serious consequences as a result of less and less groundwater are reduced crop yields and land subsidence, especially in coastal regions, according to the study published in the Nature journal.
Co-author Scott Jasechko, from University of California, emphasised that “excessive withdrawal of groundwater for irrigated agriculture in dry climates” is a major reason for groundwater decline.
The study has found that dry areas with extensive croplands have been the hardest hit. Regions which have been experiencing sharp decline in groundwater include northern China, Iran and western USA.
Quite alarmingly, over one-third of the aquifer systems studied revealed an annual drop of at least 0.1 metre (3.94 inches) from 2000 to 2022, while 12% witnessed decline of over 0.5 metre annually.
Some of the most affected aquifers in Spain, Iran, China, and the United States experienced yearly reductions greater than 2 meters during the same period.
Since the beginning of the millennium, around 30% of aquifers have witnessed an acceleration in rate of groundwater depletion. Signs of recovery, because of local conservation efforts and policies, are “relatively rare.”
The study has said that aquifers can be replenished by diverting water from other sources, but Jasechko said much more effort is needed to reverse the widespread downward trends.