對一物種進行長期監測調查可以探討該物種族群的變化，進而瞭解其未來的可能發展動向。近年由於人為過度開發而影響氣候的變化，造成許多物種無法適應而族群量縮減，甚至是瀕臨滅絕。本研究的目標物種為槲櫟(Quercus aliena Blume var. aliena)，其在臺灣野外族群數量極小，本團隊於2012年底至2020年持續對槲櫟族群進行監測，並針對其族群存活數量、小苗更新狀況、樹冠幅大小、樹高變化以及林木健康度進行調查，以瞭解其族群的變動。　　研究結果發現，槲櫟族群逐漸縮小，2014年起每年至少有6株植株死亡，但是卻鮮少發現新的植株，自然更新的小苗僅有2015年較多，也發現大多數小苗生長速度偏慢，甚至尚未大幅成長就死亡。自2013年存活至2021年的槲櫟中，過半數植株之樹冠幅和樹高則有縮減現象，樹冠大幅減少的植株大多也伴隨著樹高變矮，整體成樹的林木健康度則偏向衰弱。目前發現颱風帶來的強風造成槲櫟族群植株斷裂嚴重，而伴生樹種競爭激烈，密集的草本以及藤本植物掩蓋與攀附也嚴重干擾槲櫟的生長，因此槲櫟族群生長勢漸弱，許多植株頂端枯萎但是基底卻長出許多萌櫱，之後便逐漸死亡，而目前的氣候變化也增加槲櫟生存的危機，同時又受到人為嚴重盜採果實的影響，小苗更新不易。因此為了維持槲櫟族群生存，必須積極地進行相關的保育措施與持續進行監測，才能避免臺灣槲櫟族群消逝滅絕。

The long-term recorded survey data, which focuses on single species, can provide detailed information to understand the population changes. It is also useful for exploring the future situation trend of the species. Due to the industrial revolution and over development caused by humans, the global climate has been severely damaged. The changes resulted in an unbearable environment for many species and gradually reduced their population size or even became extinct. The target species studied in our research was Quercus aliena var. aliena in a small and isolated population in Hsinchu County, Taiwan. From 2012 to 2020, we kept monitoring their population size, seedling regeneration, individual canopy width, tree height and health condition in order to understand the population dynamics change. Our results showed that the population of Q. aliena var. aliena was decreasing. Since 2014, at least six adult individuals have died annually but few new individuals recruited. However, the naturally regenerated seedlings were observed mostly in 2015. Most of them were dead before they performed fast and significant growth. The crown width of canopy and tree height of the dwarf and adult trees which survived from 2013 to 2020 were both reduced in more than half. In most of the monitored trees, the tree height reduction was highly associated with crown width shrinking, so the adult trees were determined unhealthy. We also recorded that, in a short period, the windy typhoons frequently attacked Taiwan severely caused the tree trunk breakage. The nearby dominant trees, herbaceous plants and climbing vines all interrupted the growth of Q. aliena var. aliena. Therefore, the vitality of Q. aliena var. aliena became weaker and they started to show wilting tree top with active basal sprouting and finally died. The climate warming also increased the survival risk in Q. aliena var. aliena. The illegal collection of acorns was considered another threat critically escalated the difficultly in seedling regeneration. In conclusion, continuous monitoring and necessary conservation strategies must be enforced to ensure the population size of Q. aliena var. aliena and to avoid its extinction in Taiwan.