The sandstorms in Beijing are actually "dust storms". The dust is blown to Beijing from dried salt lakes, wasteland, and degraded grassland, said experts from the Institute of Geology under the Chinese Academy of Geological Sciences (CAGS) on Wednesday when attending an academic seminar.

Han Tonglin, a researcher from CAGS, said that on April 16, last year, a total of 336,000 tons of sand fell in Beijing in the form of a large sandstorm. After the sandstorm, he and his 7 other fellow researchers carried out an investigation in Hebei and Inner Mongolia. Later they wrote two reports on the research results titled "The Nature of the Sandstorms in Beijing and Tianjin and How to Handle Them" and "Proposals on the Beijing and Tianjin Sandstorms Handling Work". The two reports aroused high attention from the State Development and Reform Commission, which later responded to their reports. Both reports give scientific analysis of the sandstorm happening in Beijing on April 16 from geological environmental perspective. The two reports conclude that the sandstorm that occurred on that day was caused mainly by dust in the dried salt lakes in Inner Mongolia, and some by dust from wasteland and degraded grassland. Since deserts and sand land contained little dust, they were not the sources for the sandstorm that occurred on April 16 in Beijing.

For the past 50 years, people in Beijing and Tianjin have tried to control sandstorms by planting many trees. However, this method has not been very effective, because the sandstorms in Beijing and Tianjin are not actually "sandstorms" but "duststorms". The dust can be blown to 2,000-3,000 meters high in the air by wind before it falls down to the ground. Trees can not stop such dust at all, said Lin Jingxing, one of Han's fellow researchers.

In order to prevent such duststorms, people should improve the ecological environment of dried salt lakes. Instead of trees planting , more grass should be grown on the earth.

(Chinanews.cn April 13, 2007)