Under particular threat is the Chengdu plain, a source of grain since ancient times, the China Daily reported, citing the Sichuan forestry department.

The reason is spreading desertification of the Ruo'ergai Grassland, located 300 kilometers (190 miles) away at an altitude of between 3,500 and 4,000 meters (11,700 and 13,300 feet) above sea level, according to the paper.

Since the 1980s, 37,000 hectares of grassland have been turned into desert, amounting to nearly four percent of the entire area of Ruo'ergai county, the paper said.

The Ruo'ergai Grassland was covered in green pasture until a few decades ago, when the number of cows and goats grazing there suddenly started multiplying, the paper said.

In 1958, the area was home to 344,000 head of livestock, rising to more than 900,000 according to the latest count four decades later, the paper said.

More than a quarter of China's total land area has been classified as desert and the degradation is adversely affecting the lives of more than 400 million people, or 30 percent of its population.

China now has 2.64 million square kilometers (1.05 million square miles) of land under desertification, or nearly 2.5 times the country's total farmland, government statistics show.

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