由館藏標本探討溫度變化對臺灣熱帶及溫帶植物花期之影響

Using Herbarium Collections to Evaluate the Influence of Air Temperature on Plant Flowering Time in Tropical and Temperate Taiwan

全球暖化已逐漸改變許多生物的物候現象，雖然大多數地區仍缺少長期的植物物候調查紀錄，但是透過植物標本館保留的採集標本，仍可評估過往至現今的植物物候變化情形。本研究以恆春半島、蘭嶼的熱帶植物及高山地區的溫帶植物為對象，藉由查閱台灣主要植物標本館之館藏標本及氣象站紀錄，檢驗氣溫變化對於這些地區植物花期的影響情形，並找出具有潛力的指標性物種。分析的結果顯示高山地區的植物開花期集中於夏季，且有較高比例的物種開花日與氣溫呈現明顯的負相關，亦即氣溫升高容易導致植物出現提前開花現象，因此推測高山地區之溫帶物種比恆春半島、蘭嶼的熱帶物種更適合作為氣候變遷的指標。本研究初步評估，具有氣候變化指標潛力的物種有6種，包括分布在蘭嶼的貝木，以及分布在高山地區的玉山卷耳、臺灣龍膽、玉山薄雪草、短距粉蝶蘭、臺灣黎蘆。

Global warming has influenced many animal and plant phenological phenomena. Although most areas lack long-term plant phenological records, researchers can still estimate plant phenological changes from the past to present through the specimens reserved in herbarium. Our study focused on tropical species of Hengchun Peninsula, Orchid Island, and temperate species in high mountain areas. Based on the specimens in Taiwan's main herbariums and weather station records, we examined the influence of air temperature change on plant flowering time in tropical and temperate Taiwan, and tried to find potential indicator species. The results show that the flowering time of high mountain specie were more synchronized and concentrated in the summer, and higher proportion of species showed negative correlation between mean annual flowering date and annual mean temperature. We propose that the flowering time of high mountain area species is more sensitive to climate change than the Hengchun Peninsula and Orchid Island species. Six species were evaluated as having the potential to be indicator species of climate change. They are Timonius arboreus on Orchid Island, and Cerastium trigynum, Gentiana davidii, Leontopodium microphyllum, Platanthera brevicalcarata, Veratrum formosanum in high mountain areas.