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|CHONGQING， Sept. 3 (Xinhua) -- Chinese scientists announced they have converted sand into fertile soil using a new method they developed， which they hope to use to fight desertification.
A team of researchers from Chongqing Jiaotong University has developed a paste made of plant cellulose that， when added to sand， helps it retain water， nutrients and air.
A 1.6-hectare sandy plot in Ulan Buh Desert in Inner Mongolia Autonomous Region，north China， has been transformed into fertile land， yielding rice， corn， tomatoes， watermelon and sunflowers， after being treated by the new method.
A forthcoming issue of the English-language journal "Engineering，" published by the Chinese Academy of Engineering (CAE)， will publish the research by the Chongqing scientists Yi Zhijian and co-author Zhao Chaohua.
The new method will hopefully help turn desert areas into an ideal habitat for plants， said Yi.
The plants in the sandy test plot needed about the same amount of water as those grown in regular soil， but required less fertilizer and bore higher yields， according to estimates by experts.
Since 2013， scientists have been experimenting with outdoor cultivation at two sites with areas of approximately 550 and 420 square meters in Chongqing， where scientists simulated desert landform conditions.
The plants have survived the heavy rain and high temperatures， the typical climate conditions in Chongqing.
The crops， including rice， corn and potatoes， flourished in the newly converted soil， according to the scientists.
To verify the method， a large-scale planting experiment in Ulan Buh Desert began in April this year. There is very little rain fall in the area.
The converted sand has proved to be an ideal habitat for plant species with a strong resistance to wind erosion， according to the research findings.
The paste is non-toxic， environmentally friendly， cheap， and suitable for mass production， they said.
The cost of sand conversion is between 22，500 yuan and 40，500 yuan (3，373 to 6，071 U.S. dollars) per hectare， Yi said.
Enabling plants to thrive in deserts just like in soil is a major breakthrough said， Li Jia'na， with the China Agro-technological Extension Association.
The new method is an important breakthrough in combating desertification and may prove fundamental in transforming deserts into fertile， arable land， said Zhong Zhihua， an academic with the CAE.
Desert control is a global challenge. If the sand conversion method could be used on a large-scale for agriculture it could help address several environmental problems， such as deforestation， bio-diversity loss and climate change， the paper said.
There have been no publicized studies internationally about this method， according to Zhong， and the paper itself cautioned that its experiments had all been carried out in places with underground water.
Despite the lack of rainfall， Ulan Buh Desert has abundant underground water reserves， perfect to support irrigation.
Large-scale desert control through the sand-to-soil conversion "must take into consideration the risks of excessive or undue exploitation of underground water resources，" the paper said.
Before the large-scale application， planning and assessment must be carried out， and this might start in areas with access to adequate water resources， the paper added.
By Michael Place
RIO DE JANEIRO， Aug. 14 (Xinhua ) -- South Africa's Wayde van Niekerk revealed that words of support from Usain Bolt helped drive him to break the world record in the 400m final at the Rio Olympics on Sunday.
The 24-year-old claimed the gold medal by clocking 43.03 seconds， beating the previous record held by American Michael Johnson by 15 hundredths of a second.
Grenada's Kirani James grabbed silver in 43.76 seconds with the USA's Lashawn Merritt taking bronze in 43.85.
Van Niekerk said he had spent time with seven-time Olympic gold-medallist Bolt in Jamaica earlier this year.
"I was over there for about two weeks training，" Van Niekerk said. "He's been such a huge rock， inspiring me as an athlete. He told me back in Jamaica that 'you will break the world record'. And he came to me tonight and said 'I told you you can do it'."
Johnson's mark had been one of the longest standing records in athletics， having stood since August 1999.
Van Niekerk became the second Olympic champion from South Africa in the men's 400m after Bevill Rudd， who achieved the feat in 1920.
He admitted he was unsure what to think late in the race when his rivals were nowhere in sight.
"Yeah， I thought someone was going to catch me， because I felt very alone and I was like 'what's going on， what's going on?'，" he said.
"It gave me so much motivation to keep on pushing， keep on pushing， and as I got to the finish line I just dove for the finish line."
Van Niekerk said he prepared for the race on Sunday by watching his favorite football team， Liverpool， defeat Arsenal 4-3 in the English Premier League.
"Yes， I watched the Liverpool match before，" he said. "I was losing my mind because it was quite a tight match. I was so excited that we got the win over Arsenal. And my brother's an Arsenal fan. Now I've got the world record and Liverpool beat Arsenal. I've got a lot to brag about tonight."
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