Use of chemicals 'threatens grain output'

Use of chemicals 'threatens grain output'

The heavy use of agrochemicals has led to a severe deterioration of arable soil and poses a serious threat to domestic grain output.

The situation has led to some leading ecologists calling on authorities to reduce the use of pesticides and chemical fertilizers.

Despite floods and droughts, China's grain production hit 546.4 million tons in 2010, the seventh consecutive year of growing output.

"But this (grain growth) will not last long if the government fails to take timely and effective measures, as the soil is already too poor to support high-yield crops," Jiang Gaoming, a leading researcher at the Chinese Academy of Sciences, said.

The average level of organic matter in soil, which is crucial in determining crop output, is now 1 to 5 percent for northeast China's arable land, compared with 8 to 10 percent in the 1950s, according to figures from the academy's institute of soil sciences.

Statistics from the Chinese Academy of Agricultural Sciences (CAAS) also show that more than one-third of land now has harder and thinner tillage layers, which mean crops cannot be planted as deep.

Jiang said the problems have been caused by the massive overuse of chemical fertilizers over the past 30 years, following China's pledge to realize grain self-sufficiency.

Annual grain output increased from 320.56 million tons in 1980 to 546.4 million tons in 2010, according to the National Bureau of Statistics.

However, since 2007 China has been the world's largest consumer of chemical fertilizers, using more than 50 million tons every year, four times the amount in the 1980s.

"More chemical fertilizer, more grain output - that's been a common misunderstanding among government officials and farmers for dozens of years. Crops were always fertilized, regardless of cost, to guarantee high production," Jiang said.