Nature, not human activity, is to blame for sandstorms that plague the arid and semi-arid areas of northern China, according to a new study by mainland scientists.
After more than a decade of field research, Wang Xunming and his colleagues from the Cold and Arid Regions Environmental and Engineering Research Institute in Gansu concluded that the tiny dust particles which make up the sandstorms originated in rocky areas in China's northwest and were formed by floods, glaciers and strong winds over tens of million years.
Such dust, according to Dr Wang, is rarely found in deserts and sand dunes, and areas desertified through human activity cannot have been the source of sandstorms. He said the team's analysis revealed that sandstorms had actually been declining since the mid-1980s and were at their rarest and weakest in five decades.
The trend of desertification had been reversing in northern China in recent years, but the reversal was due to climate change rather than human conservation efforts.
Once the wind blew weaker, he said, plants could grow better.
'The favourable cycle is entirely initiated by nature, and it can turn bad when it changes its mind one day,' Dr Wang said.
