Change in flowering dates of Japanese Cherry Blossoms (P. yedoensis Mats.) on campus of Wuhan University and its relationship with variability of winter temperature

Change in first-flowering dates and its correlation with climatic factors was mainly analyzed, and several predicting models for the first-flowering dates were established based on the flowering dates of Japanese Cherry Blossoms (P. yedoensis Mats.) during 1947–2008 on campus of Wuhan University and the climatic data in the same period. The results show that: 1) in 1947–2000, the first-flowering dates advanced with 2.17 d per decade, with an overall trend of 11.72 d in the 54 years, the fading dates were postponed for only 1.83 d in the same period, and the florescence duration increased by 13.55 d; 2) the first-flowering dates have negative correlation with monthly average temperature from December to March. The increasing winter (from December to February) temperature is the main reason for the advancement of the first-flowering dates. Per 1°C increase in average temperature of February and wintertime makes the first-flowering dates advance by 1.66 d and 2.86 d, respectively; 3) some statistical models of the first-flowering dates were built up with average temperature of February and wintertime based on the data during 1947–2000, and they are detected independently during 2001–2008