鴛鴦湖自然保留區位於臺灣東北部新竹縣及桃園縣境交界，其集水區係源自大漢溪之上游，高度自1,650公尺至2,432公尺。自然保留區面積共374公頃，全湖包括沼澤區面積共約3.6公頃，但湖面僅2.2公頃。此自然保留區蘊育著豐富的珍稀植物，其植物相共185種維管束植物，分屬71科115屬；蕨類植物14科，23屬，33種；裸子植物3科，3屬，4種；雙子葉植物46科，70屬，108種；單子葉植物8科，19屬，22種。出現種類較多之科有蕨類的水龍科7種，薔薇科9種，冬青科8種，杜鵑花科10種，均屬溫帶樹種。然而，在溫帶較優勢的穀斗科與樟科植物在本區內極為罕見，只出現7種。以優勢度（包括相對密度及覆蓋度），雙向列表分析法及降趨對應分析本區之植被，再配合環境因子而歸納出六型植物即： （一）森林植物社會，包括：第一型：臺灣扁柏型（Chamaecyparis obtusa var. formosensis type），第二型：柳杉人工型（Cryptomeria japonica plantation type）；（二）水、溼生草本植物社會，包括：第三型：高山芒型（Miscanthus transmorrisonesis type），第四型：眼子菜型（Potamogeton octandrus type），第五型：東亞黑三稜型（Sparganium fallax type）及第六型：水毛花型（Schoenoplectus mucronatus type）。此六型植物以扁柏林為主要優勢種，並有自然更新的機能，吾等認為其植物消長已近末期而呈現一個穩定的植物社會。
The Yuanyang Lake Nature Preserve is located in the northeastern part of Hsinchu County, Taiwan. It is the uppermost head water of the Tahan River watershed at 1,650-2,432 m altitude. The total area of the natural preserve is about 374 ha, of which the lake occupies about 3.6 ha and the marshy area encircling the lake about 2.2 ha. The surrounding hillsides are dominated by cypress forests. Floristic analyses by means of Two-Way Indicator Species Analysis (TWINSPAN) and Detrend Correspondence Analysis (DCA) were conducted at the site. The findings of the former analysis concluded that the forest could be divided into two communities, namely a coniferous-hardwood community, and a swamp or early succession community. The former comprises (a) Chamaecyparis formosensis, C. obtusa var. formosana, Tsuga chinesis and (b) Rhododendron mariseii-Rhamus cranata. The swamp or early succession community comprises (a) Potamogeton octandrus, Sparganium fallax and Schaenoplectus mucronatus, (b) Miscanthus transmorrisonesis and Schoenoplectus morrisonensis. In total, there are 185 species of vascular plants, in 115 genera and 71 families. The cypress community has reached its stable stage, and Chamaecyparis species are capable of self regeneration. A successional trend of vegetation in the nature preserve area was proposed; however, the mechanism of the successional trend on the aquatic communities needs further investigation.
關聯:
Botanical Bulletin of Academia Sinica 41:1 民89.01 頁61-72
