National Geographic : 2012 Sep
Precious Water Many farmers already struggle to get enough water for their crops. Foods like beef, which people crave as they become more affluent, take far more water to produce than fish or plants. Water-efficient techniques like drip irrigation, conservation tillage, and mulching help make the most of a dwindling resource. New, less thirsty varieties of crops will help too. But ultimately we will have to learn to sip where we once gulped. ---Nancy Shute WATER COSTS Animal production (in red) requires large volumes of water for feed, drinking water, and maintenance. 10.8 4.5 3.2 2.4 2.3 2.2 1.9 1.4 1.3 0.5 0.5 Water footprint* per unit of nutritional value, quarts/kcal ROOTS CEREALS LEGUMES/PULSES VEGETABLES MILK FRUITS PORK EGGS CHICKEN SHEEP/GOAT BEEF PHOTO: REBECCA HALE, NGM STAFF. GRAPHIC: JASON TREAT, NGM STAFF SOURCE: MESFIN MEKONNEN AND ARJEN HOEKSTRA, UNIVERSITY OF TWENTE, NETHERLANDS *Defined as the total volume of fresh water used to produce each item NEXT | FUTURE OF FOOD Food demand is expected to rise some 70 percent by 2050. To help meet the need, the next green revolution is focused on aiding small farmers.