THE health of the Yellow River continues to deteriorate as it faces a series of manmade challenges that endanger its entire ecosystem, experts said yesterday.

Li Guoying, director of the Yellow River Conservancy Committee, said the waterway - known as the cradle of China's early civilization - is suffering from pollution, silting and a dramatic decrease in water flow.

Li said the overuse of water resources was threatening the river's life.

Sixty percent of the water in the Yellow River is used for human and economic activity, compared with an internationally recognized limit of 40 percent, Li said.

"The overuse of water has led to repeated cases of the river drying up," Li said.

An Xindai, director of the conservancy's Water Flow Control Bureau, said the amount of water flowing from the river into the sea has dropped to a tenth of what it was 40 years ago.

The Yellow River runs nearly 5,500 kilometers from its source in the Tibet-Qinghai plateau to the Bohai Sea in Shandong Province in east China. It supplies water to more than 155 million people and 15 percent of China's farmland.

About 1.3 billion tons of silt from the Loess Plateau are carried down the river each year. Some 400 million tons are washed into the river's lower reaches.

The heavy sediment has turned the river into a "waterway above the ground" as the riverbed in the lower reaches is about five meters above ground, according to Hou Quanliang, a researcher with the conservancy.

The silting in the lower reaches adds the equivalent of 667-hectares to the river's delta each year, according to the Yellow River Affairs Bureau of Shandong Province.

The central government has spent about 100 billion yuan constructing 3,000 reservoirs along the waterway and its tributaries since 1949. The economic spinoff from the reservoirs is worth one trillion yuan, said the conservancy's Li, but the cost of environmental degradation may exceed that amount.

"The Yellow River has made a tremendous contribution to nurturing the Chinese nation, but the demand of the people has far exceeded the sustainability of the river," Li said.

"It is necessary to let the Yellow River regain its health so that it can continue to support its eco-system and social and economic life."

Editor: Yan