Flowers in the Desert?

Recognized as the largest desert in the world, the Sahara Desert extends across North Africa, covering over 3 million square miles from the Atlantic Coast to the Nile River Valley. Except for an occasional oasis, this vast and barren landscape consists mainly of sand dunes, stone plateaus, surface gravel, and eroded mountains. The intense sun causes daytime temperatures to rise above 135 degrees Fahrenheit in the shade, and droughts commonly last for years. However, scientists are trying to restore the Sahara so that it can sustain life as it did many years ago.

Desert Life Long Ago

Paintings found on the walls of caves in the Sahara Desert suggest that a few thousand years ago lush vegetation thrived and covered the desert floor. Many curious and unusual insects, reptiles, birds, and other animals had access to food sources that allowed them to grow and reproduce. At that time, huge river systems and many oases supported growing and flourishing communities where many people lived.

Destruction of a Land

Research scientists believe that the land became a desert for three reasons. For centuries, wilderness tribes have wandered from place to place in search of food, water, and grazing land for their herds of animals. These nomadic people have always considered the number of animals they have as a sign of wealth. It is considered more important to have 100 sick and starving animals than 15 healthy ones. The large herds have been allowed to roam freely and graze on desert plants and grass. Over time, enormous sections of land have been left exposed, causing soil erosion. Today, the Sahara Desert is expanding southward as these wandering tribes continue to allow their animals to overgraze.

In addition to allowing overgrazing, these people cut down whatever trees they could find and used them for firewood. The sand is unable to hold on to the intense heat of the day, so nighttime temperatures often drop below freezing. Looking for warmth, the wilderness tribes stripped the desert of whatever hardy shrubs and stunted trees did grow.

As tribesmen and animals slowly consumed and destroyed the vegetation, nothing was left to hold the soil together and protect it from erosion. Wind and rain carried away precious elements, such as nitrogen, that could keep the soil fertile.

Desert Restoration

Scientists have been exploring different ways to revive and restore the Sahara Desert. Through research and experiments, they hope to be able to produce vegetation that will once again support an abundance of life.

Huge aquifers filled with large quantities of rainwater lie under much of the desert surface. Scientists believe this rainwater simply filtered down through the sand over hundreds of years and collected in these giant, rocky holding tanks. By harnessing the sun's power, scientists in the Sahara have conducted experiments in which they generated huge amounts of electricity. This electricity was then used to operate drilling machines and pumps to pull the rainwater up from the aquifers. By drilling a hole one mile deep into the floor of the desert, one machine was able to recover more than 80 gallons of ice-cold water each second, or 288,000 gallons per hour.

Scientists have had some success turning this barren wasteland into useful farmland. Today the desert is dotted with huge wheat fields irrigated by an elaborate system of pipes that carry water from the underground aquifer. Farmers have also learned that plants grow better if seeds are planted next to stones. Studies suggest that stones provide protection from the sun, allowing seeds to grow in a shady and cool environment.

Science is helping to restore the desert in other ways. Greenhouses have been built to protect plants from the sun and provide enough humidity so that less water is needed for irrigation. Another idea involves growing plants that can live on a diet of salt water, since the ocean is so close to the desert. Finally, scientists are experimenting with different ways to return life-supporting nitrogen to the soil.

The results of the desert experiments have been promising. Scientists hope that the Sahara will one day flourish with the plant life and flowers that bloomed there thousands of years ago.