Thirty years of gritty determination - China's desert warriors

En route to Shapotou, there is nothing much to see but sand: endless sand.

Shapotou in northwest China's Ningxia Hui Autonomous Region nestles where the Yellow River meets the Tengger Desert. For more than five decades researchers have been coming here to fight desertification. Li Xinrong is one of them.

"Sands are as precious as forests," is his mantra. Having been here for three decades, he clearly has a very personal perception of this arid land.

"Deserts are landmarks god has given us. They nurture special biotic resources. We must protect them."

Shapotou came into the public eye in the 1950s with the construction of the Baotou-Lanzhou Railway, an artery that traverses the Tengger Desert six times. The project ran into difficulties in Shapotou's ever shifting sand dunes: hardly an ideal substrate for railway track. That was when the first group of scientists arrived.

When the trains finally began running in 1958, Shapotou had gained worldwide fame as a paradigm of successful sand control, principally the result of the "straw checkerboard" technique.

Checkerboarding requires straw, usually wheat or rice straw, to be laid out in a grid across the desert and partially buried.

The checkerboards have remarkable, though poorly understood, windbreaking properties and help to keep dunes in place, allowing topsoil to form. When a sufficiency of soil is established, drought-resistant plants can be grown. However, a receding water table has led to recent degradation of vegetation and a decline of the fixative effect.

"We can't just sit back and relax. We must become tireless tree planters so that others may rest in the shade," said Li to his colleagues when he first arrived in Shapotou in 1987.

"Upon our arrival, my colleagues were gnashing their teeth and wringing their hands," Li recalled. "There was no toilet. There were rat holes all over our dorm. The only way to receive a radio signal was to climb up to the top of the dunes."

So isolated were that they almost starved. "In the end, we survived by eating the seeds of elm trees," Li said.

One third of China's territory faces the threat of desertification, and almost 400 million people are subject to frequent sandstorms and strong winds. An old saying goes, "People in Gansu eat three jin (1.5 kilograms) of dust every day".

Li's latest weapon in the war against erosion is a microbe which inhabits the soil crust growing from the straw checkerboards. It can lock up the soil, but the crust evolves much too slowly, taking at least five years to grow.

Li's team has extracted similar microbes from alga and moss and cultured them in the lab. When sprayed on the sand, the crust grows much faster, and holds the soil "just like a carpet."

"This biotechnology protects local plants from invasive species. It helps defend the original desert ecosystem," Li said.

Shapotou now has over 30 kinds of cultivated vegetation, including calligonum, caragana and scoparium. Biodiversity is crucial to combating desertification.

"The oldest vegetation has been here for a little over 60 years, while the youngest was planted ten years ago," said Zhang Zhishan, deputy chief of the Shapotou research center. "Time has shown that we made the right choice of vegetation for this area."

The lessons learned at Shapotou have helped many other places, such as the Muus Desert in Shaanxi province; Horqin, China's largest sandy area; and Erdos in Inner Mongolia. Researchers from the Middle East and Africa have been trained in Shapotou.

"Our work here can easily be transferred to central Asia," said Li, who is now working on a system to monitor transpiration rates of various plants and stimulate natural ground cover in different regions.

"Data from field observations can be inaccurate, or below international standards. Li's research is an important benchmark and all our data can be freely shared," said Zhang.

"Despite decades of research, we still know very little about deserts," Li said. "I believe deserts, generally regarded as a threat to oases, may also have positive effects on greenbelts. There's so much that remains to be explored."