- 期刊
萬里桐熱帶復舊林：乾旱火災後的動物群聚現象
TROPICAL FOREST RESTORATION ON WANLITONG: CROWDED FAUNA AFTER DROUGHTS AND WILDLAND FIRE
摘要
本研究探討臺灣南部恆春西海岸，於2015年乾旱後火災與動物相重建之過程，可做為未來極端氣候變遷下森林復育之參考。萬里桐試驗林於2008年開始局部移除銀合歡，並進行熱帶低地的復舊造林，有17種原生樹種撫育迄今，林下棲地動物相復原良好。在自動相機記錄中，活動量居首位的優勢物種是白鼻心(54%)、赤腹松鼠(23%)，和和其他鼠類(20%)，皆為植食動物。到了2014-2015年連續二年乾旱，恆春年雨量分別只有1489、1480 mm的降雨，為十年平均值的65%左右，在2015年3月之乾季末期遂有一場小規模林火，焚燬樣區共1.72 ha中的0.56 ha (32.5%)，主要在試驗林南段。本研究同時亦記錄到海岸林兩種猛禽的出沒與繁殖狀態，受益於植食動物的群聚避災現象。掠食者持續盤據未燒到的試驗林北段，關聯於高密度的松鼠與家鼠族群，間接受益於當地防風原生樹與新復育植株對鼠類供食的混生設計。自動相機所記錄之優勢植食動物有：白鼻心穩定占據北段；鼠類災前在南段，災後移往北段；赤腹松鼠災後在南北段皆有增加。其中尤以鼠類和赤腹松鼠在焚毀的南段都有較大族群波動，災後從＜10%的活動量，迅速成長到33-41%重新佔回南段。整體而言，熱帶海岸林原生植群多樣的食花、食果與食葉資源，值得在復育過程中推廣並增強其生態功能。試驗所得關於災後韌性的栽植樹木特質，包括快速更新的大冇榕（稜果榕）、七里香（臺灣海桐）與繖楊；以及燒後受損輕微的海檬果、雀榕與林投，可供新造林以強化栽植樹木與動物互動之整全生態考量，俾能及早開花結果以回應野生動物的季節需求，並思考在未來極端氣候下，增加耐乾旱、耐啃咬、耐火災、高產量的原生樹種來修復野地，以即時承受災害衝擊。
並列摘要
This study documents an ecological restoration of tropical coastal forest, and the process of reconstructing mammal fauna after a wildland fire of 2015. Bird and wildlife fauna can be used as a reference for improved forest restoration in the future under extreme climate change. In the beginning, a fallowed farm on Wanlitong was restored from seventeen native tree species that built up a core forest in the southernmost coast of Hengchun Peninsula in 2008. Infrared auto-cameras were deployed across three blocks of random complete design during 2014-2016. In the rebuilt plant communities, red-bellied tree squirrel was most dominant in day time, occupying 23% of automatic camera records. Formosan gem-faced civet (54%) and rats (20%) were predominantly at night. Animal community confronted a drought peaked in 2014-2015. Respectively, there was only 1489mm and 1480mm rainfall, about 65% of the average of past- 20 years. Wildlife were disturbed by a small-scale fire in March 2015, burning 0.56 ha (32.5%) of the study regions (1.72ha). After the fire, the squirrel and rats in the next year moved back to the burned south slowly, from less than 10% of total animal activities in the burned year (2015) toward 33-41% during the recovery.