ABSTRACT
Among the developing countries, India has pioneered in the use of agrometeorological advisories in optimizing water use in agriculture. Agrometeorological advisories have a great potential to meet the challenges of the climate change impacts on water and agriculture. This chapter gives an account of Indian experiences in this regard which are relevant to other countries, particularly those with monsoon climate. Indian agriculture has to provide food for 1.2 billion people and fodder for about a billion animals. The Green Revolution in India has been made possible through the introduction of
high-yielding Mexican Dwarf wheat and IR8 rice varieties. The dwarf Mexican wheat varieties have an average yield of 5-6 t ha−1, as against 1.5 t ha−1 of the traditional varieties. Similarly, the IR8 rice has yields of 5 t ha−1 without use of fertilizer and 10 t ha−1 under optimal conditions. Consequently, the wheat production which was 10 million tonnes in 1960, rose to about 86Mt. in 2010-2011. Similar increases have been recorded in the case of rice (95Mt), coarse cereals (42Mt) and pulses (18Mt), totaling 241Mt. in 2010-2011 (The Hindu, July 20, 2011). At this rate, the goal of 280 Mt. of food grains for 2020, as envisioned by the Prime Minister, appears to be realizable. The Green Revolution has a dark side. As the inputs of irrigation and fertilizer are
necessary to realize the benefits of the high yielding varieties, groundwater has been intensively used for irrigation, particularly in Punjab and Haryana. During the last 30 years, the number of tube wells in India went up from 2 million to 23 million, with the consequence that the water table has been going down from 1 to 3m per year. This led to extensive depletion of groundwater and soil salinization. GRACE
(Gravity Recovery And Climate Experiment) satellite technology has made it possible to monitor the depletion of groundwater. Tiwari, Wahr, and Swenson (2009) found that northern India and its surroundings which is the home of 600 million people and the most heavily irrigated region in the world, has been losing groundwater at the rate of 54±9km3/yr. This is probably the largest groundwater loss in any comparable region in the world. Evidently this cannot go on indefinitely. There is urgent need to reverse this trend. The intensive use of fertilizer led to high nitrate levels in ground water in
Haryana −114-1,800mg/l, as against the permissible level 50mg/l, thus rendering the groundwater non-potable.
