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China has stepped up efforts to curb land erosion along the Yellow River, the nation's second longest waterway in the past five years, said the Yellow River Water Conservancy Committee under the Ministry of Water Resources.

The current sand content in the water has dropped by 300 million tons a year, compared with the previous annual average of 1.6 billion tons, said the committee, which is based in Zhengzhou, capital of Central China's Henan Province.

Erosion-affected land in the Yellow River area stood at 430,000 square kilometers in 1997, but damage to 190,500 square kilometers has been brought under control over the past five years.

Land protection projects have been launched in more than 200 counties on the Loess Plateau, the main source of sand in the river. These projects include returning farmland to forest and grassland.

Meanwhile, the Yellow River can expect dry runs more often than ever due to a shrinking water supply, says a newly released geologic report.

The geological survey around the river's source area in Northwest China's Qinghai Province was started in 1999 and jointly conducted by the Qinghai Geological Survey Institute and the China Geological University.

Zhang Senqi, a senior engineer from the institute and member of the survey team, said three factors coincided to reduce the water supply: the declining groundwater levels, the deteriorating ability of local vegetation to conserve water and the extremely cold winters that can freeze the river's entire flow.

In Madoi County which is closest to the river's source, underground water levels are dropping at an annual average rate of 0.1 meters and the land suffering severe desertification is expanding at an annual average rate of 5.33 percent, the survey found.

Statistics from the Madoi hydrological station reveal that the river dried up in 1960, 1979, 1997, 1998 and 1999 with its longest dry period lasting for more than seven months.

Li Haihong, an expert with the Qinghai Meteorological Bureau, said the dry runs had severely affected the normal life and the production of people in the middle and lower reaches and led to a further deterioration in the local ecology.

(Xinhua News Agency December 23, 2002)