By ANDREW MARTIN

CAIRO - Global food shortages have placed the Middle East and North Africa in a quandary, as they are forced to choose between growing more crops to feed an expanding population or preserving their already scant supply of water.
For decades nations in this region have drained aquifers, sucked the salt from seawater and diverted the mighty Nile to make the deserts bloom. But those projects were so costly and used so much water that it remained far more practical to import food than to produce it. Today, some countries import 90 percent or more of their staples.
Now, the worldwide food crisis is making many countries in this politically volatile region rethink that math.
The population of the region has more than quadrupled since 1950, to 364 million, and is expected to reach nearly 600 million by 2050. By that time, the amount of fresh water available for each person, already scarce, will be cut in half, and declining resources could inflame political tensions further.
“The countries of the region are caught between the hammer of rising food prices and the anvil of steadily declining water availability per capita, Alan R. Richards, a professor of economics and environmental studies at the University of California, Santa Cruz, said via e-mail. “There is no simple solution.
Losing confidence in world markets, these nations are turning anew to expensive schemes to maintain their food supply.
D jibouti is growing rice in solar-powered greenhouses, fed by groundwater and cooled with seawater, in a project that produces what the World Bank economist Ruslan Yemtsov calls “probably the most expensive rice on earth.
Several oil-rich nations, including Saudi Arabia, have started searching for farmland in fertile but politically unstable countries like Pakistan and Sudan, with the goal of growing crops to be shipped home.
“These countries have the land and the water, said Hassan S. Sharaf Al Hussaini, an official in Bahrain’s agriculture ministry. “We have the money.
In Egypt , government officials say they are looking into growing wheat on 800,000 hectares straddling the border with Sudan.
Economists and development experts say that nutritional self-sufficiency in this part of the world presents challenges that are not easily overcome. Saudi Arabia tapped aquifers to become self-sufficient in wheat production in the 1980s. By the early 1990s, the kingdom had become a major exporter. This year, however, the Saudis said they would phase out the program because it used too much water.
“You can bring in money and water and you can make the desert green until either the water runs out or the money, said Elie Elhadj, a Syrian-born author who wrote his doctoral dissertation on the topic.
Egypt, too, has for decades dreamed of converting huge swaths of desert into lush farmland. The most ambitious of these projects is in Toshka, a Sahara Desert oasis in a scorched lunar landscape of sand and rock outcroppings.
When the Toshka farm was started in 1997, the Egyptian president, Hosni Mubarak, compared its ambitions to building the pyramids, involving roughly 200,000 hectares of farmland and tens of thousands of residents. But no one has moved there, and only 12,100 hectares or so have been planted.
The farm’s manager, Mohamed Nagi Mohamed, says the Sahara is perfect for farming, as long as there is plenty of fertilizer and water.
“You can grow anything on this land, he said, showing off fields of alfalfa and rows of tomatoes and grapes . “It’s a very nice project, but it needs a lot of money.
Economists say that countries in this region should grow crops for which they have a competitive advantage, like produce or flowers, which do not require much water and can be exported for top dollar. For example, Doron Ovits, 39 , runs a 60- hectare tomato and pepper empire in the Negev Desert of Israel. His plants, grown in greenhouses with elaborate trellises and then exported to Europe, are irrigated with treated sewer water that he says is so pure he has to add minerals back. The water is pumped through drip irrigation lines .
A pumping station outside each greenhouse is equipped with a computer that tracks how much water and fertilizer is used.
“With drip irrigation, you save money. It’s more precise, he said. “You can’t run it like a peasant, a farmer. You have to run it like a businessman.
Egypt is establishing an estimated 80,000 hectares of farmland in the desert each year, even as it loses 24,300 hectares of its best farmland to urbanization, said Richard Tutwiler, director of the Desert Development Center at the American University in Cairo. “It’s sand, he said, referring to the reclaimed desert land. “It’s not the world’s most fertile soil.
As Cairo’s population has grown - to an estimated 12 million today - hastily constructed apartment buildings have sprouted among the fields.
Outside of Cairo, Talaat Mohamed’s 1.2 hectares of sweet potatoes are squeezed between four-, five- and seven-story apartment buildings .
“The Egyptians invented farming, he said, peering despairingly at a landscape of electric wires and buildings, traffic and trash. “And this is what it has become.