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Northwest China is of high importance, said an article in the Economic Daily. Many areas in Gansu Province and the Ningxia Hui Autonomous Region in Northwest China which used to be rich pastures are now endangered by desert encroachment, the article said.

Cultivation of land in the area, which originated in the beginning of the Qing Dynasty (1644-1911), has helped support the growing population there. But its direct result has been the shrinking percentage of forest coverage.

It is estimated that there are a total of 1.7 million square kilometers of desert across the country, 700,000 square kilometers of which are part of the Gobi Desert, 620,000 square kilometers are ancient desert, and 380,000 square kilometers came into being in the Han Dynasty (206 BC-AD 220) and especially in the past century.

Human activity, especially farming and herding, in the last two decades produced 60,000 square kilometers of desert. Mainly located in the north, these lands become the major source of sandstorms, a frequent visitor to Beijing in recent years.

The Gobi is covered by a natural shell which prevents dust from being transported by the wind. Sand from the ancient deserts are too heavy to be blown away. But the remaining lands that do not have a long history of being deserts are rich in soil and humus and attractive to farmers. As long as there is drought and wind, sandstorms can be caused easily on these lands, according to the article.

In order to improve the ecological environment, the central government implemented a policy of converting farmland into pastures and forests in 1998.

More than a policy shift, the conversion of farmland into pasture and forest will benefit not only the nation and the people, but also humankind in the future.

The article stressed the necessity and urgency of implementing this policy. It also added that the conversion should be carried out in line with specific local conditions.

In most cases, the key to improving the current ecological environment is to stop farming and herding, and let nature cure itself, the article said.

As of June 10, there was more than 100 millimeters of rain in Ningxia and Gansu this year, which is said to be one of the biggest amounts in several decades. Many areas have been covered by indigenous grasses because of the precipitation.

It is said that 52 percent of vegetation was restored in Dulan County of Qinghai Province after farming and herding were stopped for two years although the annul precipitation was only 90 millimeters there.

Artificial planting of grass can be of great assistance in other cases.

In a farm developed with ecological technology in Alxa League in the Inner Mongolia Autonomous Region, alfalfa of high nutritional value to livestock was irrigated with the water from the Yellow River. On this farm, the grass was irrigated, harvested and stored by machines. Other plants of high economic value were also grown to make profits.

Grasses can be grown for profit in areas where irrigation is accessible or where annual precipitation is over 400 millimeters. In other areas, the conversion of farmland into pasture should rely on nature.

A plan implemented in areas near Lanzhou, capital of Gansu Province, has successfully restored the green coverage of a mountain by planting trees, and 80 per cent of the planted trees have sufficient water.

But such efforts should only be made if the environmental conditions are right, the article said.

According to experts from the Lanzhou-based Cold and Arid Regions Environmental and Engineering Research Institute at the Chinese Academy of Sciences, it is impossible to turn the deserts in the northwest green by growing trees on a large scale. Only an annual precipitation of 400 millimeters can support trees. And an annual precipitation between 200 and 400 millimeters can support shrubs.

The experts pointed out that it would be against nature to plant trees where conditions are not proper, but there are many kinds of shrubs that can survive in the northwest.

The practice has proven that the best plan to restore green coverage in the northwest is to plant trees, shrubs and grasses according to local conditions, and shrubs are preferred among the three, said the article.

Judging from the situation in the northwest, it is not enough to improve the ecological environment simply by prohibiting farming and herding. To create more room for nature to cure itself, it is necessary to move people out of the region. What is more, it will also be an effective way to raise the incomes of local people.

The experience in Xilingol League in Inner Mongolia indicates that the migration of 2,000 local residents would revive 5,000 square kilometers of grassland.

Ningxia has also established a well-run system to help people migrate to areas where irrigation is more convenient, encourage them to adjust agricultural production and even establish processing enterprises for the products.

In order to protect and improve the ecological environment in Northwest China, the article gave some suggestions.

The focus of fighting desertification should be clearly laid out. It is neither possible nor necessary to turn all desert into green land. The Gobi and ancient desert are integrated parts of the natural environment in Northwest China, and they pose no danger to people in any sense if left alone.

The land that needs treatment is the 380,000 square kilometers that has became desert due to human activity in the last 2,000 years. Special attention should be paid to the 60,000 square kilometers of desert that are no more than two decades old. Repair work should begin with the area between deserts and oases.

To ensure the advancement of ecological protection, the most important step is to move people from the region to places where irrigation is more convenient and agriculture is easy to develop. The government should lend a hand in their movement.

The experiences in the Inner Mongolia Autonomous Region, Guizhou Province, Yunnan Province and the Ningxia Hui Autonomous Region in migration should be copied and promoted.

Irrigation projects should be established to make full use of water. Aside from raising water prices properly, the article pointed out that agriculture in this area should be restructured and the practice of wasting water should be eliminated.

(China Daily August 3, 2002)