Simulating spatiotemporal variation in full-flowering dates for tree peonies (1955-2011) in the middle and lower reaches of the Yellow River, China: using a panel data model

Abstract:

In China, the tree peony (Paeonia suffruticosa) is well known as the “king of flowers” since ancient times. The springtime flowering of it attracts a great number of tourists every year. Under the current background of rapid climate change, the flowering time of the tree peony has changed accordingly, which affected the travel arrangements of tourists. This paper is concerned with developing a panel data model to describe the relationship between full-flowering date (FFD) of the tree peony (Zhongyuan cultivar group) and relevant temperature change in the middle and lower reaches of the Yellow River. Then FFD time series at 24 sites in the period 1955–2011 were reconstructed using the above-mentioned model. At last, spatial and temporal variations in FFD were analysed. The results showed that the panel data model could simulate the FFDs of the tree peony accurately, with explained variance (R²)>0.65 and the root-mean-square error (RMSE)＜4.0 in the steps of double cross-validation. The simulated 57-year mean FFDs in the distribution area generally followed the latitudinal gradient. The FFDs in this area have advanced by 6 to 9 days over the past 57 years, at the rate of 0.8 to 1.8 days/decade. Compared with the other sub-areas in this area, the eastern forelands of Taihang Mountains and Luliang Mountains showed clearer advances of FFD. These conclusions reflected the comprehensive impact of climate change and the foehn on phenophases and are helpful for historical climate studies and festival events management