Abstract: Global climate change affects ecosystem processes by altering vegetation phenophases. However, there is few consensus on how vegetation phenophases respond to climate change at the regional scale. By using the Google Earth Engine platform and MOD09GQ, MOD13Q1 and MOD11A1 satellite data products from 2000 to 2020, we analyzed the latitudinal zonality of vegetation phenophases and the influence of temperature on forest vegetation distribution in the Greater Khingan Range. The results showed that there were significant variations in the latitudinal gradient of vegetation phenophases in the study area, and that the start of growing season (SOS) advanced on average by 0.34 d for each degree of latitude increase. Similar to the SOS, the end of  growing season (EOS) increased on average by 0.19 d for each degree of latitude increase. The length of growing season (LOS) exhibited a curvature change with an inflection point at around 50°N, and was shortened on average by 1 d for each degree of latitude increase before the point, and prolonged on averaged by 0.57 d for each degree of latitude increase after the point. SOS and LOS were more sensitive to latitude changes than EOS. Among them, the extension of LOS was mainly caused by the fact that the advance of SOS was more significantly than that of EOS. In addition, temperature directly affected vegetation phenophases in the study area, with stronger effect on SOS and LOS than on EOS. The effect of temperature in April on SOS and LOS was the most significant. The higher the temperature, the earlier SOS and the longer the LOS. The increase of LOS was mainly due to the advancement of SOS and the delay of EOS was relatively short in magnitude. The study of large-scale vegetation phenophases is principal supplementary for understanding the responses of ecological processes to climate change, with implications for forest zoning management.

Key words: vegetation phenology, latitudinal zonality, Google Earth Engine, Greater Khingan Range.