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The land desertification in northwest China is still on the expansion. The "Strategic Study on Disposition of Water Resources, Construction of Ecological Environment and Sustainable Development in northwest China" published on February 25, 2003 by the Chinese Academy of Engineering holds, the land desertification has constituted a major crisis affecting the ecological environment in northwest China.

The result out from the comparison of a group of numerical data deserves our attention. According to the comparison of the two surveys done by State Forestry Administration in 1994 and 1999, the area of land desertification expanded by 52,000 square km in a time-span of five years. It is an annual average net expansion of 10,400 square km, of which the annually net expansion of desertified land came to 3,436 square km. 1999 saw the desertified land come to a total of 2.674 million square km all over the country. However, that in the northwest China took up around 2.183 million square km.

The land desertification in northwest China is a critical and comprehensive representation of all problems, such as drought and shortage of water, drying-up of rivers and lakes and water and soil erosion and so on that cropped up during the long evolution of ecological environment in the region, the study report by the Chinese Academy of Engineering puts forward. Among the total areas of the land desertification due to unreasonable exploitation of water and land resources in the northwest that can be returned to the normal come to a total of some 600,000 square km or so.

Why sandstorms turn out much fiercer?

The report is of opinion that this must be ascribed to the expansion of land desertification in northwest China over the past few years.

In China, the areas in which sandstorms highly erupted fall into the following four categories: 1) desert and sandy soil, wilderness, Gobi Desert and grassland; 2) exposed and loose loess on the Loess Plateau; 3) crisscrossed area of pastureland and grassland on the north and south of the Yinshan mountain; and 4) cultivated dry-land in the semi-dry zone in north China lack of vegetation protection. Of the four categories, except that coming into being due to the geological factors in history all belong to the confines of land desertification. The comparison of the two surveys carried out by the State Forestry Administration in 1994 and 1999 tells that in a time-span of five years the area of land desertification expanded by 52,000 square km. It is an annual average net expansion of 10,400 square km, of which the annually net expansion of desertified land came to 3,436 square km. The report shows that the expanded areas of land deterioration mainly happened in northwest China.

The northwestern area referred to in the research report is meant for the inland water reaches (including international watercourses in Xinjiang) and the Yellow River reaches in the six provinces and autonomous regions of Xinjiang, Qinghai, Gansu, Ningxia, Shaanxi and Inner Mongolia. Those participating in the research include 35 experts and academicians in the Chinese Academy of Engineering and Sciences.

(People's Daily March 4, 2003)