Feature Stories

World Water Day 2005:  Water for Life

It is possible to grow economically useful plants, such as barley, varieties of wheat, dates, and olives, in saline waste land using saline ground water (Photo credit: IAEA).

Washing Out the Soil

Utilizing Saline Groundwater Productively in Agriculture

(From World Water Day 2002)

To raise crops in the dry soil around Faisalabad, wells had to be dug 30 metres, sometimes deeper, to tap water scarce water beneath Pakistan´s arid central plains, says Dr. Mujtaba Naqvi. After only a couple of hours, pumps would sputter and run dry.

So at the turn of the 20th century when dams were built and a network of canals turned the plains of north Pakistan green, there was rejoicing. But silently and unnoticed, the irrigation system began to blight the land it had brought to life. Seepage from the network of unlined channels was raising the water table, washing salts from the soil into water, becoming saltier, as it moved higher.

At the surface sunlight and wind evaporated the water. Only the salt remained. Its touch withered plants and killed soil organisms, creating dead and barren wasteland.

From Morocco to China, Canada to Australia - as a result of human activity, irrigation, or removal of tree cover - 77 million hectares, an area twice as big as Germany, is devastated by salt and salt water, according to the Food and Agricultural Organisation (FAO).

About 16 million hectares of land in Pakistan are irrigated by a network of canals and tube wells and 26 percent of it is affected, to different degrees, by salinity.

"There are some regions where there is so much salt on the land, when people see pictures of it they think it is snow," said Dr. Naqvi. Naqvi, the former head of Pakistan´s Nuclear Institute for Agriculture and Biology, is a biochemist and provides technical advice to a nine-country IAEA programme that is successfully using salt ground water to irrigate crops.

According to FAO estimates, the advance of salinity renders three hectares of land barren every minute, adding to the amount already devastated by human action and to the several hundred million hectares of salt land that occur naturally in Earth´s arid regions.

Around the world, seven per cent of land - one million square kilometres - is salty and the estimated one billion people living in arid regions associated with it suffer high rates of poverty, malnutrition and illiteracy. Many flee to the slums of sprawling urban centres.

In Australia salt land and the saline water beneath it is known as the white death.

"No one uses salty water in agriculture. You normally dig channels and take it out of the system," said Dr. Naqvi.

But the Earth´s human population can ill afford to lose resources to meet the needs of its rapidly increasing numbers. To provide the food for the Earth´s growing population, the FAO calculates that in the next 30 years over 200 million hectares of additional agricultural land will be needed. Shortages of fresh water may also force agriculture to adapt to coastal zones and make use of seawater for irrigation to grow crops.

Most of the water on the planet is salty, not only in its seas, but also in the ground water beneath arid regions defined by geography and geology. Dr. Naqvi has demonstrated that even this salty ground water can be put to use to feed the planet.

More than a quarter century since he began exploring the possibilities for using salt ground water, he and an international network of scientists are making salt lands bloom. Their techniques are being taken up by more and more farmers, based on the success of projects in Pakistan, in Morocco, Tunisia, Egypt, Syria, Iran, Jordan, the United Arab Emirates and Algeria.

It has taken the accuracy of tools provided by nuclear science and technology, close observation of nature, and in the case of Dr. Naqvi, tenacity and passion, to achieve the startling results.

Humans make commercial use of only two per cent of the 250,000 higher species of plants, many of which are salt tolerant. In the IAEA project, with technical advice from Dr. Naqvi, 30 salt tolerant plants, from pistachio trees to barley and Acacia, were selected and are growing in Pakistan´s salt lands, arid saline regions in Morocco, Tunisia, Egypt, Syria, Iran, Jordan, the United Arab Emirates and Algeria. The IAEA initiated the project, helps to train experts, and continues to provide financial and technical support to the project.

Food crops, fodder for animals, and firewood are being grown on the saline lands, using saline ground water for irrigation with minimum cultivation and no fertiliser, or pesticides. In the areas selected for cultivation, nuclear techniques provided critical information about whether crops could be maintained: by determining that the source of water would not run out and how to use it without building up more salt deposits.

"We have shown that it is possible to grow economically useful plants, such as barley, varieties of wheat, dates, and olives, in saline waste land using saline ground water."

Dr. Naqvi took the view that water, not its quality, should be seen as the constraint because "even if you have water whose salinity is from sea water you can still grow something. It is up to you to make it economically viable."