Chinese scientists have launched the world's first experimental plant project for sucking poisonous arsenic from soil.
Chen Tongbin, a senior researcher with the Chinese Academy of Sciences (CAS) Institute of Geographic Science and Resources, said Saturday in an interview with Xinhua that he led to build three experimental sites in Hunan, Zhejiang and Guangdong provinces, for tryouts in removing heavy metal elements from soil.
The one-hectare experimental site in Chenzhou, central Hunan Province, are planted with 30 tons of a kind of arsenic-sucking plant, with a scientific name of Pteris vittata L. The plant could remove 10 percent of arsenic from the soil in one year, Chen said.
Soil recovery technology depends on poison-accumulating plants, widely regarded as "hyper-accumulators" in academic circles. The heavy metals accumulated by those plants are to be recycled. The primary targets of the technology are arsenic, copper and zinc.
A global leader in technology for collecting arsenic from soil, Chen's team, which is sponsored by the state hi-tech development program, proved that Pteris vittata L., a brake fern widely found in southern China, has a strong ability to draw arsenic from the soil.
After Pteris vittata L., Chen's team found another dozen of hyper-accumulators, which could be used in the future for soil cleaning.
His team have applied for more than 20 patents, with two invention patented and one design patent being granted.
Since the 1980s, global scientists have blazed a new way in cleaning polluted soil with hyper-accumulators. Decontamination by plants and recycling technologies would make heavy industries lessen environmentally damaging.
Statistics showed that 20 percent of China's farmland was polluted by heavy metals, which caused 10 million tons of crop losses annually.
It is estimated that soil recovery technologies through plants might have a market worth two billion US dollars in the coming two years.
(Xinhua News Agency November 5, 2005)
