China will cover the slopes on both sides of the 1,110-kilometer-long Qinghai-Tibet Railway with cold-resistant grass to form a "green great wall" on the Qinghai-Tibet Plateau.

The project along what is known as the roof of the world is expected to cost 1.2 billion yuan (US$145 million) which will be provided by the central government, said Lu Chunfang, an official in charge of the construction.

Explaining the advantages of the scheme, Mou Ruifang, an associate professor from the Southwest China Communications University, said the roots of the grass will help stabilize the soil while the grass itself will protect both the roadbed and the slopes from heavy rain.

Though the railway is not as long as the Great Wall, which stretches for more than 6,000 km along the ridges of two mountain ranges and runs through at least seven Chinese provinces and autonomous regions, it will be a great eco-wall maintaining the ecological balance of the Qinghai-Tibet Plateau, Mou added.

Grass in a 10 by 100 meter experimental area beside the railway has survived the frigid winter. Early next spring workers will begin the extensive grass-planting on gradient slopes which range from three to 10 meters in height.

The planting of grass alongside the railway line will be a challenging undertaking as more than 960 kilometers, or over four-fifths of the railway, will be at an altitude of more than 4,000 meters with 547 kilometers, or half its total length, being laid on long-frozen earth.

"We will take effective measures to preserve the moisture, temperature and soil nutrients," said Bao Liming, a senior engineer of the No. One Railway Survey and Design Academy.

Tests have proved planting in this way raises the grass survival rate to 70 percent, doubling the natural growth rate, he added.

The gigantic afforestation scheme also includes conservation of the bush areas the railway cuts through, and the building of 30 animal tunnels to ensure antelope and other species can pass over the railway safely after the line opens to traffic.

The 1,956 railway extends from Xining, capital of northwest China's Qinghai Province, to Lhasa, capital of the Tibet Autonomous Region in southwest China. It will be the first railway to link Tibet with the rest of China.

The section between Xining and Golmud City was completed in 1984 and areas surrounding it were planted in grass and trees. Work on the line connecting Golmud with Lhasa started in June 2001and is expected to be completed by 2007.

Afforestation along the 1,956-km-long railway line is an important part of the project. This is because ecological balance in the region is fragile.

The Qinghai-Tibet Plateau is the source of major rivers in both China and some southeast Asian countries and home to many rare plants and animals.

(Xinhua News Agency October 28, 2002)