Policy Update 025

Agriculture and Environmental Problems in Uzbekistan

YAMASHITA Kazuhito
Senior Fellow, RIETI

Purpose of my business trip to Uzbekistan

In late November I traveled to the Central Asian country of Uzbekistan on business. Tashkent is the capital of the republic. There are also many historic towns and cities including Samarkand, a Silk Road city that flourished as a trade center. The purpose of my visit to Uzbekistan, which was made on the request of the Japan International Cooperation Agency (JICA), was to provide technical assistance to the country in preparation for its accession to the World Trade Organization (WTO). More specifically, I organized a seminar and lectured to Uzbekistan government officials on the mechanism of the WTO agreements and other matters.

Actually, there was another aim of my visit to Uzbekistan. I wanted to see the Aral Sea, which is known as a site of the most devastating environmental destruction of the 20th century. In the 1950s, irrigation projects were vigorously promoted in Uzbekistan and Kazakhstan diverting water from the Syr Darya and Amu Darya rivers. As a result, the water volume of the Syr Darya decreased and the Aral Sea, into which the river flows, was lowered in water level and diminished in size. Moreover, the increased salinity of the sea water has turned the Aral Sea into a dead sea uninhabitable by fish.

Unfortunately, this second aim was not realized during my visit this time. The Aral Sea is far away from Tashkent; I was told that that I would have to take a flight to the nearest airport and then drive some 200 kilometers from what used to be the seashore to the point at which the body of water is viewable. Merely hearing this is enough to convince me of the scale of environmental destruction.

Instead of traveling all the way to the Aral Sea, I inspected the situation of the Syr Darya region where irrigation projects were promoted. Here, the land is badly affected by salinization (salt damage).

What is salinization?

In arid areas, rainfall is so scarce that irrigated agriculture is carried out by diverting river and ground water to farming fields. This does not cause any problem if such sprinkled water is properly discharged. If it is not, however, the water stays in the soil and the salt in the soil begins to dissolve. Furthermore, water that seeps from the surface into the soil connects with the saline groundwater by the capillary phenomenon. In arid areas, evapotranspiration under the scorching sunlight is so high that salt in the soil is brought to and stays at the surface of the ground by the capillary phenomenon as water evaporates. When salt accumulates in the surface soil layer, the land is not arable.

In Uzbekistan, the water accumulated in the surface soil layer is flushed out with massive amounts of water in winter, which further dries up the Aral Sea.

Where salt accumulation is extremely severe, salt-contaminated soil needs to be removed. This is a form of soil loss through salt damage, which also poses a serious problem. Plants usually grow roots in the top 30 centimeters of the soil layer. However, it takes an estimated 200-300 years to form 1-centimeter-thick soil, meaning that the top 30 centimeters of the soil layer has slowly developed over 6,000-9,000 years. Losing this is tantamount to giving up the capability for agriculture. Salt damage has been blamed for as the cause of the fall of Mesopotamian civilization.

To be sure, irrigated agriculture in arid areas has its positive side; crops suffer little pest damage thanks to lower humidity. However, the problem of salt damage is becoming increasingly global; for instance, in newly developed upland farming areas in Australia, the Midwestern region of the United States, and areas along the Black Sea. In southern Iraq where Japan's Self-Defense Forces are dispatched, salt damage is severe and a scene resembling a snow-covered land is spreading. A United Nations report on agriculture and the environment warns that 80 million hectares, out of the 260 million hectares of irrigated farmland worldwide, is suffering from salt damage.

What about Japan?

In places like Japan where rainfall is relatively high, salt in the soil is usually washed away by rainwater and saline groundwater would not rise because of the high seepage pressure of water from the surface. Thus, salt would not be brought to the surface of the ground.

Rice paddies have cleverly prevented the occurrence of salt damage. Rice paddies are a mechanism in which the flow of water takes in nutrient elements from forests and washes away infectious agents and salt from within the soil. That is, rice paddies have been letting the problem of salt damage, literally, drift away with the water. Indeed, it is thanks to this mechanism that the Changjiang basin has remained fertile for 7,000 years. Rice paddies also work to prevent the soil from draining with water and wind by holding rainwater and covering the surface soil with that water.

What is the solution?

Pursuing high profits in a short period of time leads to ill-fated agriculture, which ignores the possibility of salt damage and other potential problems, because it is costly to properly treat drainage. In other words, this is unsustainable agriculture. Should the current trade practice remain unchanged, farm production in countries practicing unsustainable agriculture such as the U.S. and Australia will further expand while sustainable but feeble farming in Asian rice paddies will shrink. This is not the problem of trade per se; practicing of unsustainable agriculture is what should be blamed. In order to ensure food security, Japan must urge the U.S., Australia and other developed countries from which it imports food to properly address various problems including the one of salt damage. At the same time, Japan needs to extend assistance to help promote sustainable agriculture in developing countries such as Uzbekistan.

The original text in Japanese was posted on December 14, 2005.

January 27, 2006

January 27, 2006

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