Trudging up a sand dune about five meters high outside the town of Cele County at the southern edge of China's largest desert, Taklimakan, Gui Dongwei could not help but exclaim "amazing."

As large as ten soccer fields, it was once one of the moving dunes of Taklimakan, the world's second largest moving desert. The desert had forced the town of Cele to relocate three times in history, but Gui saw it being enclosed by green trees.

That was 2007, when Gui, a doctoral candidate, went for the first time to the Cele Research Station of the Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences (CAS). Since then, he has accompanied many scientists and experts from home and abroad up the dune to relate how his predecessors "locked" the moving dunes with trees.

"There were many dunes like this surrounding the town. But all of them have been changed into farmland, with only this one left since it's too large. And it's a reminder of history," said Gui, now vice director of the Cele Research Station.

Since China proposed the Silk Road Economic Belt initiative, aiming to rejuvenate the ancient trade route, experts have worried whether people could cope with serious desertification along the route.

Sustainable development of the oases is crucial to the success of the construction of the Belt.



Writing on sand
Cele County in Khotan Prefecture, south of China's northwestern Xinjiang Uygur Autonomous Region, is extremely dry, with annual precipitation of only 35 mm and annual evaporation exceeding 2,500 mm.

Every year, the county sees about 20 days of sand storms, 90 days of blowing sand and 150 days of floating dust.

For the last thousand years, the desert has consumed more than 20 towns along the ancient Silk Road in Xinjiang. As recently as the 1980s, several towns, including Cele, Pishan and Minfeng, were threatened by intruding sands.

In these circumstances, the CAS Xinjiang institute set up the Cele station in 1983 to study the arid environment and the sandstorms. The station has since helped prevent the invasion of desert.

In 1995, the United Nations Environment Program awarded Chinese scientists two honors for controlling drifting sand and breeding desert plants.

"Southern Xinjiang still lags in the research of oasis ecology and deserts," Gui said. "We need to know how to achieve sustainable development."

After his academic pursuit in the United States from 2011 to 2014, Gui turned down a few better-paid job opportunities and chose to return to Cele.

"I have a strong attachment to my home Xinjiang," Gui said, "we can make world-class achievements on the barren land with advanced technologies and research methods as long as we persist."

"The real research should be written on the ground to embed our accomplishments, not just on academic journals," he said.



Sea of death
Huang Ziyou, 52, and his wife live in a shack of less than 10 square meters in the heart of the Taklimakan Desert. The bed next to the stove, their home is actually coded No.021 well pump chamber.

For seven years, the couple have spent 12 hours each day in maintaining a well and a pump connected by many thin, black pipes, in the noises of a diesel generator. These pipes provide drip irrigation to the shelter forest of the 522-kilometer highway running through Taklimakan.

After breakfast, Huang inspects the pipes along his 4-kilometer patch everyday. In this remote place with neither television signals nor Internet connection, the plants flourish and protect the highway through the moving desert.

Taklimakan, covering 337,600 square kilometers, is one major petroleum bed. In 1995 PetroChina invested 800 million yuan (127 million U.S. dollars) in building the highway, which, however, has since faced a serious threat of burial and soaring costs for maintenance.

A shelter forest was built from 2003 to 2006 on both sides of the highway, with a total investment of 218 million yuan.

Xu Xinwen, director of the CAS Taklimakan Desert Research Station, said the green corridor has decreased wind speeds on the highway by 50 to 77 percent and the volume of moving sands in the shelter forest is only 0.98 to 12.55 percent of that in drifting sand areas.

"The shelter forest has curbed damage to the highway and improved the ecological environment," said Xu, who has worked in the desert for more than two decades.



Balanceing oasis and desert
Li Xinhu everyday weighs sand and soil in 12 huge barrels on an underground scale, and calculates the evaporation volume according to the change in weight.

The scale, or lysimeter developed by the CAS Water Balance Research Station in Aksu, measures the evaporation volume with an accuracy of 0.01 mm.

Director Zhao Chengyi said his station, located in the largest oasis in the Tarim Basin, is an ideal site to study the changing patterns of water and salt of the oasis farmland ecosystem.

"The oases in Xinjiang are expanding," Gui said. "What we are focusing on is to keep a balance between oasis and desert."

"The use of water is the key to realizing the sustainable development of oases," Gui said.

Researchers said the underground water in Khotan is still within sustainable limits, but on a decreasing trend.



Green technologies
The desert prevention and control technologies developed by Chinese experts have been introduced to countries in Central Asia and Africa, including Turkmenistan, Egypt, Libya and Mauritania, said Lei Jiaqiang, deputy director of the CAS Xinjiang institute.

The Chinese have helped design the wind and sand prevention project for a coastal highway and a desert highway in Libya, and a forestation project for a natural gas base in Turkmenistan, Lei said.

They have also been asked to provide technological support to the construction of the Great Green Wall Initiative, a pan-African project to green the continent. The project is also aimed at tackling poverty and the degradation of soils in the Sahel-Saharan region, focusing on a strip of land of 15 km wide and 7,100 km long from Dakar to Djibouti.

Ramadan Mohammed, a researcher with the Egyptian Desert Research Center, said the sand control project in the northern Sinai Peninsula has employed technologies developed in China, such as covering and fixing dunes with crop straw and gravel.

"China's sand control technologies are simple but effective with low resource consumption," said Ramadan, adding that Arab countries also have their own sand control technologies that might help China.