Drover's Cattle, "More Than 150,000 Breeding Cattle Leave Texas in 2011 Drought," February 2012, http://www.cattlenetwork.com/e-newsletters/drovers-daily/More-than-150000-breeding-cattle-leave-Texas-in-2011-drought-138513934.html.

339 will run completely dry before the end of this decade

"Dry Lake Mead? 50-50 Chance by 2021 Seen," MSNBC, February 2008, http://www.msnbc.msn.com/id/23130256/ns/us_news-environment/t/dry-lake-mead--chance-seen/#.UGSvsBh9lbo.

340 has dropped more than 100 feet

Brown, Plan B 4.0.

341 two minutes on average, twenty-four hours a day

Charles Duhigg, "Saving US Water Systems Could Be Costly," New York Times, March 14, 2010.

342 like groundwater resources-"out of sight, out of mind"

Ibid.

343 vast new quant.i.ties of needed freshwater

Power, "Peak Water."

344 agricultural irrigation practices are still extremely wasteful

T. Marc Schober, "Irrigation: Yield Enhancer or Farmland Destroyer?," Seeking Alpha, July 11, 2011, http://seekingalpha.com/instablog/362794-t-marc-schober/194359-irrigation-yield-enhancer-or-farmland-destroyer; "No Easy Fix," Economist; World Health Organization, "Progress on Drinking Water and Sanitation: 2012 Update."

345 farmers have been slow to make the change

Sandra Postel, "Drip Irrigation Expanding Worldwide," National Geographic, June 25, 2012.

346 amounts of salt that build up with continued use

World Wildlife Fund, "Farming: Wasteful Water Use," 2005, http://wwf.panda.org/what_we_do/footprint/agriculture/impacts/water_use/.

347 safe for watering plants

Nancy Farghalli, "Recycling 'Grey Water' Cheaply," NPR News, June 2009, http://www.npr.org/templates/story/story.php?storyId=105089381.

348 purify it, and put it into drinking water systems

Kate Galbraith, "Taking the Ick Factor out of Recycled Water," New York Times, July 25, 2012.

349 communities have successfully implemented the approach

Ibid.

350 more of the rainfall and store it for drinking water

Peter Gleick and Matthew Herberger, "Devastating Drought Seems Inevitable in American West," Scientific American, January 2012.

351 roughly 10 percent of the Earth's surface

Susan Lang, " 'Slow Insidious' Soil Erosion Threatens Human Health and Welfare as Well as the Environment, Cornell Study a.s.serts," Cornell Chronicle, March 2006.

352 accelerate the emission of carbon dioxide into the atmosphere

Personal conversation with Rattan Lal.

353 increasing the fertility of the topsoil

David R. Huggins and John P. Reganold, "No-Till: The Quiet Revolution," Scientific American, July 2008, pp. 7077.

354 replenish soil carbon and nitrogen

Michael Pollan, The Omnivore's Dilemma: A Natural History of Four Meals (New York: Penguin, 2006), p. 42.