China's top environment watchdog will begin environmental impact assessment on the Qinghai-Tibet railway this week.

"The State Environmental Protection Administration (SEPA) will focus its attention on the examination of the protection of ecosystems around the construction site of the Qinghai-Tibet railway," said Zhu Xingxiang, head of the administration's Department of Environmental Impact Assessment.

The Qinghai-Tibet railway, the highest-altitude railway in the world, is built on the Qinghai-Tibet Plateau in northwestern China, where the ecosystem is primary, unique and fragile.

The plateau is the place of origin of the country's five major river systems - the Yellow River, Yangtze River, Lancang River, Nujiang River and Yarlung Zangbo River. Also, the plateau is the home to some rare wildlife, such as the Tibetan antelope, wild ass and snow leopard.

The mean annual temperature of the plateau is between -4 C and 6 C. Once vegetation is destroyed it is almost impossible to recover.

"For protection of the vegetation along the railway line, we required that earth excavation for construction be carried out at least 500 metres from the railway lines," said Zhu. "And every piece of vegetation removed must be replaced."

The other problem concerning SEPA is whether or not the freedom of migration of Tibetan antelopes will be influenced.

Although September is not the best season for the examination of this problem, some investigations will be carried out, according to Zhu

Every year, the migration period for the antelope is from June to August.

During the period in 2002 and 2003, to ensure smooth migration the project was temporarily suspended, Zhu added.

Special passageways for the migration of Tibetan antelopes and wild yaks have been designed and built. And passengers will see some signs along the railway reminding them about the wildlife.

"We will also check the infrastructure construction of pollution control and prevention mechanisms," said Zhu.

The country pays high attention to environmental protection during the project.

It has invested 1.2 billion yuan (US$148 million) so far, the most spent on environmental protection during a railway construction project in the country.

Work on the line from Golmud in Qinghai Province, to Lhasa, a distance of 1,142 kilometres, began on June 29, 2001. About 960 kilometres of the track are over 4,000 metres above sea level, with the highest point 5,072 metres.

The project will be ready for trial operation by next July.

(China Daily September 19, 2005)