Why Water Will Be the Driving Force behind Agricultural Sustainability.

In the latter half of the 20th century, world population more than doubled to 6 billion; staple food prices in constant dollars decreased dramatically; and the nutritional status of the world’s population improved. The Green Revolution is cited as accounting for this paradox; but often ignored is the impact of increasing irrigated acreage, irrigation efficiency and water use efficiency on the effectiveness of the green revolution of improved plant varieties and fertilization. From 1950 to 2000, irrigated area in the world more than doubled; and the acreage irrigated through pressurized systems increased greatly while water applied per unit area decreased. In our increasingly water short world, efforts to address the World Hunger problem must be cognizant of the interacting effects of water, plant species and variety, and soil fertility. In this presentation, examples from the Middle East, Central Asia and the USA will highlight ways in which water management is key to crop water productivity.