Impacts of climate warming on plants phenophases in China for the last 40 years

Based on plant phenology data from 26 stations of the Chinese Phenology Observation Network of the Chinese Academy of Sciences and the climate data, the change of plant phenophase in spring and the impact of climate warming on the plant phenophase in China for the last 40 years are analyzed. Furthermore, the geographical distribution models of phenophase in every decade are reconstructed, and the impact of climate warming on geographical distribution model of phenophase is studied as well. The results show that (ⅰ) the response of phenophase advance or delay to temperature change is nonlinear. Since the 1980s, at the same amplitude of temperature change, phenophase delay amplitude caused by temperature decrease is greater than phenophase advance amplitude caused by temperature increase; the rate of phenophase advance days decreases with temperature increase amplitude, and the rate of phenophase delay days increases with temperature decrease amplitude. (ⅱ) The geographical distribution model between phenophase and geographical location is unstable. Since the 1980s, with the spring temperature increasing in the most of China and decreasing in the south of Qinling Mountains, phenophases have advanced in northeastern China, North China and the lower reaches of the Changjiang River, and have delayed in the eastern part of southwestern China and the middle reaches of the Changjiang River; while the rate of the phenophase difference with latitude becomes smaller.