物候学方法在历史气候变化重建中的应用

利用历史物候记录重建的气候变化结果，显著地增进了人类对过去气候变化特征的认识。但现有研究在历史物候记录的提取与处理、重建方法的选择、重建结果的精度评估等方面需要进一步总结梳理。通过归纳历史物候记录的资料源以及在历史物候记录预处理过程中需要解决的物种鉴别和物候期确定问题，对现有重建方法进行总结，发现较早的研究采用了古今对比法，而近年来的研究多采用更为复杂的回归和过程模型法。上述物候学方法的重建结果对认识中世纪暖期、小冰期和近百年等典型时段的历史气候变化特征提供了重要依据，同时物候学方法重建结果与其他代用资料重建结果往往表现出较高的一致性。未来研究可在历史物候记录的整编与利用、重建方法的准确性评估与改进以及不同重建结果比对等方面，进一步深入开展工作。

The application of phenological methods for reconstructing past climate change

Climate variations inferred from historical phenological records enhance our understanding of the characteristics of the past climate changes. However, the extraction and processing of historical phenological records, the selection of the reconstruction method and the assessment of reconstruction results need to be further summarized. This study first analyzed the data sources and spatial distribution of historical phenological records. Then we discussed pre-processing issue in phenological reconstruction studies such as identification of plant species and specific phenological phases. With regards to the reconstruction methods of past climate changes, we found that earlier studies used the simple comparative method, i.e. directly comparing phenological timing in ancient vs. modern times to reflect climate change. Recent studies often used more complex methods, such as regression and process-based models. Regression models combine the timing of phenological events with climatic factors without considering specific biological process, while process-based models formally describe known or assumed cause-effect relationships between biological processes and some driving factors, e.g. certain environmental variables for plants. The reconstruction results derived from these methods have been conductive to recognize historical climate changes in typical periods of the past 2000 years such as the Medieval Warm Period, the Little Ice Age and quick warming during the last 100 years. In addition, reconstruction results derived from the phenological evidences are consistent with the results derived from other paleoclimatic proxy data, such as tree rings and lake sediments. In the future, in order to obtain more solid and pronounced conclusions in this field, it is necessary to investigate the extraction techniques of historical phenology records, to improve the reconstruction methods and to comprehensively compare the previous reconstruction results, as well as to improve problematic approaches.