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Perhaps no one is better prepared for hot, dry summers than Israel's farmers. The Israelis, using drip irrigation and other techniques, have made plants bloom on land that has been barren for millenniums. Portions of the arid Negev, an area once written off as largely uncultivable, today grow fruit, flowers and winter vegetables eagerly sought by European markets. Through a process known as "fertigation" -- dripping precise quantities of water and nutrients at the base of individual plants -- crops can be grown in almost any soil, even with brackish water.
Plant genetics is another option that needs to be energetically pursued. At / the University of California at Riverside, plant physiologist Anthony Hall is working on a way to make cowpeas more tolerant to heat. Other scientists are using genetic engineering to transfer genes from bacteria that act like natural insecticides. But though they have tried, scientists have not yet been able to develop farm crops that are drought resistant. Says Hall: "You can't grow plants without water."
There are things people can do if the well runs dry. Several communities located near the sea have built desalinization plants. Denver, meanwhile, has pioneered the unsavory concept of turning sewer water into drinking water. In 1985 the city opened an experimental plant that produces 1 million gal. a day of high-quality H2O from treated effluent.
Some scientists have suggested that the depletion of the ozone layer could be counteracted by a variety of Star Wars-like techniques. They include lofting frozen ozone "bullets" into the upper atmosphere and blasting apart ozone-depleting molecules in the air with huge terrestrial laser beams. But such grandiose schemes would be unreliable and could change weather patterns in unpredictable ways. In the end, it may be safer and cheaper, if inconvenient, to cope with ozone depletion by wearing wide-brimmed hats, sunglasses and sunscreen.
Man has always shown a great capacity for adjusting to change. Past generations have survived floods and ice ages, famines and world wars. But when dealing with the environment, there is a grave danger in relying on adaptation alone: societies could end up waiting too long. Many of the global processes under way, like the wholesale destruction of species, are irreversible. Others, like global climate changes caused by man, are so profound that if allowed to progress too far, they could prove to be overwhelming. Simple prudence suggests that taking forceful preventive action now -- to save energy, to curb pollution, to slow population growth, to preserve the environment -- will give humanity a much better chance of adapting to whatever comes in the future.