Below are extracts from an article written by Charles Whelan and published by Seed Magazine:

TAIPUSI, China (AFP)—Officials in Inner Mongolia say they have established a living barrier of trees, grass and shrubs wide enough to hold back the Gobi desert and to curb the sandstorms blowing over northeast Asia and hitting the United States.

Taipusi, one of Inner Mongolia's banners or counties, is at the centre of a project to plant a so-called Green Wall of China, designed to act as a buffer between the expanding desert and Beijing, just 200 kilometres (120 miles) to the south.

Like the original Great Wall, the green wall straddles a patchwork of counties in several northern provinces including arid Hebei and Shanxi.

But unlike the crumbling stone structure, which failed to keep out invading nomads from the north, officials say they believe the new wall will work.

"We are pretty confident it will be effective," Hu Cun, Inner Mongolia's vice director of forestry, told some 30 journalists invited from Beijing to inspect the work ahead of World Environment Day on Tuesday [5 June 2007].

"Already the number of sandstorms has been reduced," he said, saying that from 18 in 2001 the number fell to none this year, a figure disputed by experts who say four sandstorms were recorded in Beijing in March alone.

[…]

The journalists were taken to a small hill on the southern edge of the "green wall" from where they could look north towards the desert five kilometres away over a ridge.

Between the hill and the desert were hardy young poplar trees, newly planted Mongolian pine that had yet to grow beyond a metre in height, as well as apricot bushes and grassland.

"This area was in an atrocious state a few years ago," said Zhang Boawen, the deputy mayor of Taipusi, home to 230,000 people, mostly farmers or herdsmen.

One third of the entire land of Inner Mongolia is desert and the sand wilderness has been spreading for decades.

Taipusi county is in Xilongol league, a province of central Inner Mongolia which was once more than 90 percent grassland but is now overrun by the Hunsandake desert, an eastward extension of the Gobi that now claims more than 30 percent of its land.

Most of the rest of the Xilingol grassland is severely distressed by population pressure and over-grazing.

As a result of this and other factors including an extended drought, the desert has been marching southeast at a rate of three kilometres a year heading directly for Beijing. But the expansion has stopped, at least for now, officials say.

"So far we have had some success," said Hu. "The desert is being held back. However, the ecology of this arid land is very delicate and the desert has been expanding for decades. We have just begun our job so we will need more time."

Millions of trees have been planted and grass seeds dropped from airplanes, while herdsmen have been banned from fragile grassland and thousands of families have been relocated from distressed areas.

But sceptics say the root of the problem, overpopulation and unsustainable development, has not been addressed by a narrow corridor of grass and trees.

Jiang Gaoming, of the Institute of Botany at the Chinese Academy of Science, said that 60 billion yuan (7.6 billion dollars) spent on projects to control sandstorms hitting Beijing had been largely wasted.

"Do not get too excited by those recovered grasslands and forests you see alongside the highways. They only cover 10 percent of the total affected area. The other 90 percent causes the continuing sandstorms," said Jiang.

US government experts said progress had been made since the 2001 study. They described Xilingol as a "disaster area."