年初氣溫變化對於福山植物園栽植樹種花期之影響

Influences of Temperature in Early Months on the First Flowering Dates of the Planted Trees in Fushan Botanical Garden

溫帶地區的植物物候研究已證實，全球暖化現象已導致溫帶地區植物的開花期提早。然而，全球暖化對於亞熱帶地區植物開花物候所造成的影響仍尚未明朗。受到聖嬰與反聖嬰現象的影響，位居亞熱帶的福山植物園在2010年（聖嬰年）1－3月的均溫較2011年（反聖嬰年）高2.8˚C。根據園區內植栽物候調查的結果，於2010及2011年2－6月期間皆有開花紀錄的37科、102種、244株樣木，在聖嬰年平均首次開花日較反聖嬰年提前約2週，顯示年初的溫度變化確實對於園區植栽的春季開花時間造成影響，故推測亞熱帶地區植物開花物候亦會受到全球暖化的影響。從園區栽植樹種中篩選出在聖嬰年開花日明顯早於反聖嬰年的16個物種以及3個科別，其中烏皮九芎和黑星櫻普遍分布於台灣中低海拔地區，鐘萼木花大且易於觀察，而冬青科、殼斗科、薔薇科植物則普遍分布於全台灣，上述物種與分類群有潛力成為台灣地區監測氣候暖化的指標物種與科別。

Flowering phenology researches conducted in temperate regions demonstrate that increased surface temperature caused by global warming can significantly influence the flowering time of plants. However, the impacts of global warming on subtropical plant flowering phenology remain unclear. According to temperature records of subtropical Fushan Botanical Garden, the El Nino event in 2010 and La Nina event in 2011 had caused the mean temperature during January to March in 2010 2.8˚C higher than in 2011. The flowerings of 37 families, 102 species and 244 trees in Fushan Botanical Garden were investigated between February and June, and their mean first flowering dates in 2010 were about two weeks earlier than in 2011. This result suggests that the flowering phenology of subtropical plants may be also influenced by global warming. Sixteen species and three families were selected as potential indicator species and families for monitoring the influence of global warming on flowering phenology in subtropical Taiwan. Styrax formosana and Prunus phaeosticta, commonly distributed in Taiwan, and Bretschneidera sinensis, having big flowers, are suggested as indicator species. Families Aquifoliaceae, Fagaceae and Rosaceae which dominate low to middle elevation forests in Taiwan might be good indicator families.