URUMQI, Oct. 7 (Xinhua) -- China has closed fast-melting glaciers in the Tianshan Mountains to 2,000 tourists who were found to be driving their vehicles on the rivers of ice in the far western Xinjiang Uygur Autonomous Region.

The move is an attempt to preserve the glaciers which are shrinking at a rate of eight meters a year and are a source of drinking water for about 2.3 million residents of Urumqi, Xinjiang's capital.

Several years ago, a number of travel agencies started to organize unauthorized tours to the No.1 glacier of the Tianshan Mountains, according to Urumqi City Tourism Bureau.

Tickets cost only 20 yuan (about 2.5 U.S. dollars) for a visitor. Some tourists even drive on the glaciers, said the tourism bureau.

The increasing number of visitors caused a lot of pollution and left a lot of trash said the Cold and Arid Regions Environmental and Engineering Research Institute of Chinese Academy of Science.

The visitors also damaged some of the institute's research equipment at the Tianshan glacier research station, which is based in northwestern city of Lanzhou.

Over the past couple of years, the No.1 glacier has been shrinking by about eight meters a year due to global warming and increased human activity, according to observation by the Tianshan glacier research station.

The glacier in Tianshan Mountains, 120 kilometers southwest of Urumqi, is one of the most closely studied glaciers by the World Glacier Monitoring Service. Enditem