論臺灣的蕨類植物及其地理親緣關係

Taxonomy and Phytogeography of Taiwanese Pteridophytes

臺灣的蕨類植物種類繁多顯然與其地理位置、地形、氣候有關。由臺灣蕨類植物的採集史，進而指出許多亞洲植物命名上的問題，必須追溯至現存於歐洲樣本館，早期採自亞洲的標本。本研究材料主要來自作者自行收集，自民國57年至70年間野外資料，及自民國70年至73年間日本、歐洲各大標本館中資料；全臺灣蕨類植物本文確認617種，其中包含4新種，13新紀錄種，15新組合，33新異名，27新更正，1/3的學名在臺灣植物誌第一版中並未提及。臺灣蕨類植物的垂直分佈，大致與臺灣植被帶的垂直分佈相符，43.%的種類生長在臺灣的暖溫帶；在針葉樹林帶的臺灣蕨類植物，大多數是以喜馬拉雅山區為其分佈中心，同時也尋找此植被帶固有蕨類植物的最親緣種，發現其分佈中心同前。本文首次提出，將植被學的選擇重要植物觀念，運用在植物地理學上，經用此觀念，得到臺灣闊葉林帶蕨類植物的地理親緣關係如下：一、與馬來西亞植物區系關係極為薄弱；二、臺灣的亞熱帶與琉球羣島，大陸東南沿海諸省，中南半島低地，應屬同一植物地理單位；三、臺灣的暖溫帶與大陸西南諸省，中南半島北部高地，印度東北角，屬另一植物地理單位。臺灣本島雖然位於馬來西亞植物區系的北緣，但其植物地理親緣關係却顯然偏向亞洲大陸。

The position, topography, and climate of Taiwan are briefly described and shown to be very important for the richness of its pteridophytic flora. The history of botanical exploration of Taiwan is briefly described. It is pointed out that many nomenclatural problems pertaining to Asiatic plants can only be solved by work in European herbaria. The present study is mainly based on the author's field work from 1968 to 1981 both on flora and vegetation, and herbarium studies in Japanese and western European herbaria. 617 taxa were critically examined; they include 4 new species, 13 new records, 15 new combinations, 33 new synonyms, 27 new corrections. One-third of the names had not been used in Taiwanese botanical literature before. The elevational distribution patterns of Taiwanese pteridophytes agree very well with the vegetation zones in Taiwan. 43% of the Taiwanese pteridophytes belong to the warm-temperate forest zone. Most of the pteridophytes in the coniferous forest zones extend to or are mainly distributed in the Himalayan region. The closest relatives of endemic species in the coniferous forest zones were also studied; they show the same phytogeographical connections. Selective criteria are proposed for comparing floras of neighbouring regions. An analysis of the distribution of selected pteridophytes in the broad-leaved forest zones gave the following results: the pteridophytic flora of Taiwan has very weak relationships with that of Malesia; the pteridophytes of subtropical Taiwan form links with those of the Ryukyus, SE. China, and the lowlands of Indo-China; the pteridophytes of the warm-temperate zone are closely related to those of SW. China (especially Szechwan, Yunnan, Kweichow), N. Indo-China, and NE. India. Thus, Taiwan can be said to have an East Asiatic, rather than a SE. Asiatic-Malesian fern flora, in spite of its position between the two areas.