School of Ecology and Nature Conservation, Beijing Forestry University, Beijing 100083, China.
Key Laboratory of Tree Breeding and Cultivation of State Forestry Administration, Research Institute of Forestry, Chinese Academy of Forestry, Beijing 100091, China.
Sci Total Environ. 2023 Feb 25;861:160337. doi: 10.1016/j.scitotenv.2022.160337. Epub 2022 Nov 26.
Leaf phenology is one of the most reliable indicators of global warming in temperate regions because it is highly sensitive to temperatures. Temperature sensitivity (S) is defined as the values of changed days of leaf flushing date (LUD) per degree increase in temperatures. Climate warming substantially advanced LUD in the temperate region, but its effect on S of LUD is still not clear. We used spring phenological records of 12 woody plants in eastern China in the years of 1983-2014 to explore temporal and spatial changes of LUD and S. Furthermore, we compared the difference of S and preseason temperatures in two periods (1983-1997 and 2000-2014), and explored the main factors regulating S. The results showed that the average LUD significantly advanced (-2.7 days per decade). The mean LUD over the period 1983-2014 was in day of the year (DOY) 87 ± 7 across sites and species for the early leaf flushing species (EFS), and mean DOY 102 ± 5 for the late leaf flushing species (LFS). LUD was earlier in low latitude than that in high latitude. S of Armeniaca vulgaris was the most sensitive to temperature across all sites (-3.66 d °C), while Firmiana simplex was the most insensitive (-2.37 d °C). LUD of EFS was more sensitive to temperature warming than that of LFS. At the same site, LUD of EFS would advance more obviously than that of LFS under global warming. For all species, S decreased significantly with shorter preseason length and warmer temperatures at the preseason end. Our results had demonstrated a strong relationship between S and the preseason length (mean temperature at the preseason end).
叶片物候是温带地区最可靠的全球变暖指标之一，因为它对温度高度敏感。温度敏感性 (S) 定义为每度升温导致叶片展叶日期 (LUD) 变化的天数。气候变暖极大地提前了温带地区的 LUD，但 LUD 的 S 对其的影响仍不清楚。我们使用了 1983-2014 年中国东部 12 种木本植物的春季物候记录，以探讨 LUD 和 S 的时空变化。此外，我们比较了两个时期（1983-1997 年和 2000-2014 年）S 和 preseason 温度的差异，并探讨了调节 S 的主要因素。结果表明，平均 LUD 显著提前（每十年减少 2.7 天）。在 1983-2014 年期间，早展叶种（EFS）的 LUD 平均在每年的 87 ± 7 日，晚展叶种（LFS）的 LUD 平均在 102 ± 5 日。低纬度的 LUD 早于高纬度。所有地点中，杏花（Armeniaca vulgaris）的 S 对温度最敏感（-3.66 d °C），而青桐（Firmiana simplex）最不敏感（-2.37 d °C）。EFS 的 LUD 对温度变暖的敏感性高于 LFS。在同一地点，在全球变暖下，EFS 的 LUD 比 LFS 更明显地提前。对于所有物种，S 随着 preseason 长度的缩短和 preseason 末期温度的升高而显著降低。我们的结果表明，S 与 preseason 长度（ preseason 末期的平均温度）之间存在很强的关系。
