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Protective farming can cut dust storms

(China Daily)
Updated: 2008-07-31 10:15

Protective farming should be further expanded nationwide to help cope with dust storms, China Agricultural University said July 30, 2008.

By practicing protective farming, wind erosion of farmlands could be reduced by 40 to 70 percent, the university's research found.

Covering farms with straw after harvesting could effectively stop dust from rising and thus reduce the sand and silt that is blow into rivers.

This could be applied in 16 provinces in northern China.

"To prevent and control dust storms, the key is to control farmlands, to keep them from bareness," Li Hongwen, a professor at the university and head of the research team, said.

"The deterioration of farmlands is the main cause of dust storms, as pm100, granules with a diameter of less than 100 microns, can easily be blown by winds into the air and to cities and villages where people live.

"Take Beijing as an example, all dust storms are formed this way," Li said.

He said covering farmlands with straw, "surface wind speed is lowered while the soil remains moist preventing granules from being blown away".

Currently, protective farming is employed on about 2.3 million hectares in 15 provinces in northern China.

It is expected to cover 2.6 million hectares by the end of the year, the Ministry of Agriculture said.

Wang Tao, an expert on land desertification from the Chinese Academy of Sciences, said: "Human beings have to take greater responsibility for the deterioration of land.

"Protective farming should be widely encouraged."