Water management in northern states and the food security of India.

摘要

India has had a history of famines because of rainfed agriculture and rapid population growth. After the era of Green Revolution that began in the 1960s, India never experienced a famine-like situation; it did, however, experience a drought of the century in 1987. Northern states (Punjab, Haryana and western Uttar Pradesh) with a high level of irrigation are contributing almost all of wheat and two-thirds of rice to the central pool of India. Punjab has the largest area (97%) under irrigation, with a corresponding contribution (60% of wheat and 40% of rice) to the central pool. Large-scale cultivation of rice and its early transplantation facilitated by early (in the month of June) regular supply of electric power to tubewells are currently the major factors responsible for the fall of water table and indebtedness of farmers in Punjab. Shifting rice transplantation from June 10 to June 30 can arrest approximately two-thirds of the water table fall. Technologies for making efficient use of irrigation water and enhancing groundwater recharge are available. Shifting of subsidy from input (subsidized power to tubewells) to output (increase in procurement price or bonus on agricultural marketable produce) would encourage farmers to use irrigation water more efficiently. To feed India's projected population of 1.35 billion in 2025, agricultural production would have to be increased by ~25%. Agricultural production in Punjab, Haryana, and western UP might not be sustainable unless major steps are taken for improved management of groundwater.