being placed on the operating and marketing advantages gained from assembling such data as quickly as possible.
Making comparisons between water and grain requires in-depth understanding of the water situation. The world’s water supply is a fixed quantity, which can be neither increased nor depleted. Scarcity is totally a factor of use or demand. Of course, that is where the principal warnings are being sounded. Thus, attention is on the need to embrace levels of efficiency in use of the fixed supply of water, extending from agriculture through food processing to consumers. Drawing an analogy to debating whether the global supply of oil has peaked and is on decline or not, the supply of water does not change, holding at its peak, but facing the likelihood of shortages and chaos on account of wasteful use of that supply.
Few numbers are as terrifying as those used to describe the future of the water supply in relation to demand. According to the Food and Agriculture Organization of the United Nations, it was the availability of water, mainly through irrigation, that allowed the world to respond to the food needs of the global population that doubled in the last 50 years. Expanded food production was achieved in the face of a gain of hardly 12 per cent in cultivated land. Most of that new cropping area was irrigated land, which currently accounts for 20 per cent of the world’s cultivated area. But the superiority of irrigated land for crop production over rainfed regions is underscored by the estimate that irrigated accounts for 40 per cent of global agricultural production and for 60 per cent of the cereal grain outturn.
The water problem reflects the reality that expanding irrigation must take into account the water scarcity that already exists, especially in regions where population pressures are causing unsustainable crop practices. Shortages are due largely to rising populations and higher incomes, which are projected to require 70 per cent more food. Some developing regions facing those needs already have experienced water shortages. The F.A.O. says that the Middle East and East Asia “are operating very close to their limits.”
In trying to assure sufficient water to produce the grain the world is going to need, the F.A.O. is leading in stressing crop efficiency and less waste. “More crop per drop” is the motto. Yet, that only addresses a part of the problem, which some suggest would best be corrected by changes in both crops grown and foods eaten to focus on foods requiring less water. According to the F.A.O., a single slice of bread requires 40 liters of water. Bread’s position is best examined in relation to the finding that producing 1 calorie of food requires 1 liter of water, and that the world‘s average daily calorie requirement is 2,800 per person. Bread looks quite efficient in relation to, say, a hamburger, requiring 2,400 liters of water. Whatever the solution, it is obvious that avoiding water scarcity will occupy increasing attention from grain-based foods.