Thirsty crops and hungry people

Seed Daily via SPX: ...Agriculture is in fact one of the world's most insatiable consumers of water. And yet it's facing growing competition for water from cities, industry, and recreation at a time when demand for food is rising, and water is expected to become increasingly scarce. Take irrigation, for example, says Fred Vocasek, senior lab agronomist with the nation's largest crop consulting firm, Servi-Tech, Inc., in Dodge City, KS.

"Irrigation withdrawals in the United States have stabilized since about 1980, but food consumption trends are following the upward population trend," he says. "In other words, we have an increasingly hungry world with stable, or limited, freshwater supplies for food production. So, how do we keep pace with the widening gap?"

The principal answers, say the symposium speakers, lie in three areas: Protecting our limited stores of freshwater in lakes, streams, and the ground (blue water); optimizing the use of water in crop production (green water); and reusing "waste" water (gray water) that has already served some purpose, such as food processing or energy production.

But those answers also raise a host of additional questions, says Vocasek, who co-organized the session with John Sadler of the USDA-Agricultural Research Service. Who gets the water from an aquifer when farmers want it for irrigation, a gas company wants to pump it for fracking, or a city hopes to water a new golf course? How do we convince producers to adopt water-conserving technologies and practices when it's not in their economic interest to do so? Why can't farmers simply irrigate less?...

Mobile irrigation equipment on a field outside Motala, Sweden. Photo by Riggwelter, July 5, 2006. Wikimedia Commons, under the Creative Commons Attribution-Share Alike 3.0 Unported license