Smog in major grain-producing areas of China, such as the North China Plain, may lead to a reduction in grain yields, according to a recent academic report.
Tie Xuexi, a research fellow with the Institute of Earth Environment under the Chinese Academy of Sciences (CAS), published an article in June in Scientific Reports, an online journal published by the Nature Publishing Group, which said that his research team has concluded that smog could seriously affect crops' growth.
Tie's study indicates that smog could lower the amount of sunlight that crops receive by as much as 49 percent, which they speculate may lower rice yields by up to 2 percent and wheat yields by up to 8 percent, according to the institute's official website.
Tie has been studying China's smog problem since he was hired by the institute in 2009 as part of the Recruitment Program of Global Experts, also known as the "Thousand Talents Plan."
His research looked at four major crop-growing areas of China: the North China Plain, the Yangtze River Delta region in East China, Central China's Hunan and Hubei provinces and Southwest China's Sichuan Basin.
These areas contribute a combined 45 percent of the country's total rice yield and 75 percent of its total wheat yield, yet they are also the most smog-polluted areas.
Cao Junji, the director of the Institute of Earth Environment and the designer of the study, told the Global Times on Wednesday that smog's high concentration of PM 2.5 - airborne particulates under 2.5 micrometers in size - hinders plants' ability to absorb enough sunlight for photosynthesis, which causes an overall drop in the yields of crops.
Moreover, after pollutants including heavy metals sink into the soil, they will also lower the quality of the crops, ultimately affecting human health, said Cao.
He admitted, however, that the current research method relies mainly on data collected from satellites and could have been affected by many blind spots created by cloud cover.
He also pointed out that the study will help evaluate the losses caused by pollution and will help policymakers better combat smog.
（Source：Global Times）
