摘要
全球暖化是當前物種保育所重視議題，並常關注暖化對物種及生態系的影響。冰河孑遺生物應是受暖化影響最大的物種，目前太魯閣國家公園園區屬冰河孑遺生物者，如臺灣小黃鼠狼及山椒魚等脊椎動物，故以山椒魚為受暖化影響之指標生物辦理本計畫。太魯閣國家公園是臺灣產山椒魚遺傳多樣性最高的區域，在此地區分布有臺灣山椒魚、楚南氏山椒魚及南湖山椒魚，實屬太魯閣國家公園的重要資產特色。
由於近年來暖化的影響，高山氣候已逐漸改變，如氣溫升高、夏季變長、冬季變短、暴雨加劇、小雨變少等等皆可能影響山椒魚的生存，因此本計畫針對太魯閣國家公園三種山椒魚分布與微棲地喜好、族群動態、遺傳結構及親緣關係等進行研究，以利後續保育經營管理作為。
計畫的分布調查方面，一則對以往研究有記錄之處進行族群現況的瞭解，一則對園區中現今可能分布的區域進行調查。調查同時記錄山椒魚的巨棲地、微棲地的各項因子，以及個體訊息。第二項則是利用前項所得到的資料，對比於前人研究瞭解族群在這些年間的變化，以得到族群的動態資料。第三項為對臺灣山椒魚、楚南氏山椒魚及南湖山椒魚的遺傳結構進行分析。第四項為臺灣各種山椒魚間的親緣關係分析，以前述三種再加以阿里山山椒魚、觀霧山椒魚的族群，瞭解臺灣各種山椒魚的演化歷史。
本計畫共調查到89隻太魯閣國家公園之山椒魚，其中南湖山椒魚只分布在南湖中央尖區域，無論在被調查到的數量、棲地範圍與海拔分布皆是最小。臺灣山椒魚分布從南湖、中央尖山與畢祿山皆有分布。楚南氏山椒魚除過去在武嶺、合歡山至小奇萊等地有發現外，今年發現在磐石至立霧主山也有山椒魚的分布。三種山椒魚喜好利用針葉與闊葉混合的巨棲地，分別占62.86至100%。三種山椒魚亦喜歡棲息在有苔蘚遮覆之石頭質材下。臺灣山椒魚與南湖山椒魚在底質為碎石子棲地被調查到的占大多數，分別為68.57%與55.88%。楚南氏山椒魚則是在腐植土的微棲地被調查到較多，占54.29%。利用全長粒線體cytochrome b DNA序列進行遺傳親緣關係研究，臺灣五種山椒魚被分成兩大類群，其中觀霧山椒魚自成一主要類群，其親緣關係與亞洲大陸山椒魚較為接近。楚南氏山椒魚與阿里山山椒魚親緣關係較近，被分在同一類群。臺灣山椒魚與南湖山椒魚兩族群內又可以被分成兩個次類群。臺灣山椒魚在820林道族群與中央尖山族群有顯著遺傳分化。臺灣山椒魚與楚南氏山椒魚在cytochrome b遺傳多樣性較南湖山椒魚高。結合棲地、海拔分布範圍與遺傳分化資料顯示，南湖山椒魚分布範圍小、遺傳多樣性低且有遺傳分化，顯示有較強的選拔壓力，在物種保育上急需被關注。本研究同時提供一個臺灣的山椒魚一個遺傳演化路徑的假設。
Abstract
Global warming is a serious issue of protected species. We keep an eye on the impacts of it, not only on animals but also on the ecosystems. Glacial relict species like Taiwan least weasel (
Mustela formosanus) and Asiatic salamander (family
Hynobiidae) in Taroko National Park may be adversely affected by global warming, therefore, we decided to study Asiatic salamander as an indicator species of the impacts caused by global warming. There is the highest genetic diversity of Asiatic salamander in Taiwan in Taroko National Park, there are
Hynobius formosanus,
Hynobius sonani and
Hynobius glacialis inhabiting in it. Undoubtedly, they are the most important asset of Taroko National Park.
Elevation of temperature, longer summertime and strong sudden downpours due to climate change have posed a great threat to Asiatic salamander which lives in the alpine climate. We study the microhabitats preference, population dynamics, genetic structure and phylogeny of
Hynobius formosanus,
Hynobius sonani and
Hynobius glacialis in Taroko National Park for the conservation and management in the future.
Accordingly, the purposes of this study in 2016 include:
First, we investigate the place which was recorded to get the information of Asiatic salamander population, also, we do a field study on the habitats that Asiatic salamander may inhabit in them. During the field study, we record the habitats, microhabitats, and individual information. Second, we compare the data that received from the field study with previous studies to understand the population dynamics. Third, we analyze the genetic structure of
Hynobius formosanus,
Hynobius sonani and
Hynobius glacialis. Fourth, we analyze the phylogeny of all Asiatic salamander in Taiwan, includes
Hynobius formosanus,
Hynobius sonani,
Hynobius glacialis,
Hynobius fuca and
Hynobius arisanensis to understand the evolutionary process.
We collected 89 Asiatic salamanders in Taroko National Park this time, in which,
Hynobius glacialis inhabit Mountain Nanhu Gien Shan area only. The amount of
Hynobius glacialis is less, moreover, the range of habitats and altitude distribution are narrowest among five kinds of Asiatic salamander in Taroko National Park.
Hynobius formosanus inhabit not only in Mountain Nanhu and Gien Shan but also in Mountain Bilu.
Hynobius sonani was found in many places apart from Wulin, Mountain Hehuan and Chenggong Cabin. In our study, we found Asiatic salamander in Mountain Panshi and Mountain Liwu this year. These three kinds of Asiatic salamander prefer to inhabit in mixed coniferous-broad-leave forests, and it takes from 62.86% to 100% respectively, in addition, they like to stay under the rocks which were covered by moss.
Hynobius formosanus and
Hynobius glacialis prefer to stay at the ground with gravel, it takes 68.57% and 55.88% respectively; and
Hynobius sonani prefer to stay in the humid soil, it takes 54.29%.
We analyze the genetic structure and phylogeny of five kinds of Asiatic salamander in Taiwan with mitochondrion cytochrome b DNA sequence and divide them into two major groups, among them,
Hynobius fuca who is a close relative of Asian salamander is the only member of one group.
Hynobius sonani and
Hynobius arisanensis are relative-associated, so they are in the same group. It can be further divided into two sub-group in both
Hynobius formosanus and
Hynobius glacialis group. There is an obvious genetic differentiation of
Hynobius formosanus which inhabit in 820 Forest Road and Gien Shan. There is a higher cytochrome b genetic diversity in
Hynobius formosanus and
Hynobius sonani than in
Hynobius glacialis. The study demonstrates that
Hynobius glacialis has narrower distribution range and lower genetic diversity, and we need to pay more attention to its conservation. We also establish a hypothesis about the evolution path of
Hynobius formosanus.