東沙島之植物相

The Flora of Tungshatao (Pratas Island)

本文係國內外植物界首次報導東沙島植物相。東沙島屬於東沙群島，位於台灣，海南島及呂宋島之間，距高雄港約430公里，面積1.74平方公里。本島植被可分原生植被，次生植被及人工植被，植被帶以海岸灌叢為主，最顯要植物為草海桐（Scaevola sericea），伴生植物有白水木（Messerschmidia argentea），海人樹（Suriana maritima），葛塔德木（Guettardia speciosa），小葉桑（Morus australis），檄樹（Morinda citrifolia）及量較少的白避霜花（Pisonia grandis）。另有草本植被帶，以海馬齒（Sesuvium portulacastrum），芻蕾草（Thuarea involuta）。雙花蟛蜞菊（Wedelia biflora）及馬鞍藤（Ipomoea pes-caprae ssp. brasiliensis）。本島共登錄111種植物名錄，24種為栽培種，14種為馴化種。本島植物中有橙花破布子（Cordia subcordata），白避霜花，海人樹，葡匐垂桉草（Triumfetta procumbens），大花疾（Tribuluscistoides）及水韭葉絲粉藻（Syringodium isoetifolium）等6種不見於台灣及其附近小島。東沙島與西沙群島之植物相極為類似。感謝行政院農委會漁業處之經費及交通支援而完成本文。

Tungshatao, situated among Taiwan, Hainan and Luzon, about 430 kilometers from Kaohsiung harbor, Taiwan, is 1.74 square kilometers in area. The vegetation of this island can be classified into three kinds native, secondary and artificial vegetation. The most important community is coastal thicket composed mainly of Scaevola sericea mixed with members of Messerschmidia argentea, Suriano maritima, Morus australis, Guettarda speciosa, Morinda citrifolia and Pisonia grandis. The grassland, occupying a smaller part in the island, is mainly composed of Sesuvium portulacastrum, Thuarea involuta, Wedelia biflora and Ipomoea pes-caprae ssp. brasiliensis. A total of 111 species, including 24 cultivated species and 14 naturalized species. are recorded from this island. Among the natives Cordia subcordata, Pisonia grandis, Suriana maritima, Tribulus cistoides, Triumfetta procumbens, and Syringodium isoetifolium are not recorded from Taiwan proper and its adjacent islands.