Climate Change and Winter Wheat Yields in Northern China
Fang, SB, Tan, KY, Ren, SX, Zhang, XS and Zhao, JF. 2012. Fields experiments in North China show no decrease in winter wheat yields with night temperature increased by 2.0-2.5C. Science China Earth Sciences 55: 1021-1027.
Working at the Gucheng Agrometeorological Experiment Center of China's Meteorology Administration in Dingxing County, Hebei Province, and taking winter wheat as a test crop, the five researchers conducted field experiments where infrared heaters were used to increase night temperature by about 2.5°C in contrast to the normal night temperature in two whole growing seasons of winter wheat: 2008-2009 (a warmer year) and 2009-2010 (a colder year). In doing so, Fang et al. found that, in the warmer year, winter wheat yield was unaffected in the high-night-temperature treatment by the extra warming directed towards the surface of the soil and crop. In the colder year, on the other hand, winter wheat yield was increased by more than 30% in response to the nighttime warming, largely due to the fact, as they describe it, that "the higher temperatures extended the growth period before over-wintering, and significantly increased the number of tillers and effective panicles."
Given such findings, it would appear that the greater warming of daily minimum temperatures, as compared to daily maximum temperatures, has been a great boon to winter wheat production in Northern China.
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