Climate change can alter and disrupt the phenology and phenological interaction between organisms from various trophic levels in forest ecosystems. In temperate forests, the breeding phenology of birds is correlated to local microclimate, especially spring temperature to match the timing of food availability. Recent studies revealed that the temperature warming is more pronounced in high-elevation areas (elevation-dependent warming), while the breeding phenology shift of birds in this condition needs further investigation. We studied the annual change in the egg-laying dates of varied tits (Poecile varius) and a pre-breeding temperature index in three plots located along with the elevational gradient in South Korea and a low-elevation plot in Japan. We found strong support for disproportionate rates of changes in higher elevation for warming trends in pre-breeding period and advances in egg-laying dates over the last decade. Next, we compared three segments of 36-year data from Akazu Research Forest. The evidence from pre-breeding temperature during 36 years indicates that we could detect the change in thermal environment and breeding phenology with longer years of data, especially in lower elevation regions. This result shows the need for long-term research to understand the change in local temperatures and the ecology of forest birds. Our study presents evidence of elevation-dependent phenological advance in avian breeding activities and discusses the need for systematic long-term research on multiple taxa and climatic drivers in Asia.

气候变化可以改变和破坏森林生态系统中各个营养级别的生物之间的物候学和物候学相互作用。在温带森林中，鸟类的繁殖物候与当地的小气候有关，尤其是春季温度，以适应食物供应的时间。最近的研究表明，在高海拔地区，温度变暖更为明显（取决于海拔的变暖），而在这种情况下鸟类的繁殖物候变化需要进一步研究。我们研究了各种山雀（Poecile varius）的产卵日期的年度变化）和三个地块的繁殖前温度指数，以及韩国的海拔梯度和日本的低海拔地块。我们发现，对于前繁殖期变暖趋势和近十年来产卵日期的增加，高海拔变化率不成比例得到了强有力的支持。接下来，我们比较了来自Akazu研究森林的36年数据的三个部分。来自36年的育种前温度的证据表明，我们可以用较长的数据来检测热环境和育种物候的变化，尤其是在海拔较低的地区。该结果表明需要进行长期研究，以了解当地温度的变化和森林鸟类的生态。