海南霸王岭五唇兰两种生态型生态位特征

Niche characteristics of Phalaenopsis pulcherrima (Orchidaceae)with two ecotypes in Bawangling Nature Reserve, Hainan Island

关键词:  兰科植物  东亚特有种  生态位宽度  生态位重叠

Key words:  Orchidaceae  East Asia endemics  niche breadth  niche overlap

摘要:

东亚特有种五唇兰自然状态下存在叶背红色和绿色两种生态型。对海南岛霸王岭地区的五唇兰群落中草本层生态位特征进行测定和分析,探讨两种生态型五唇兰在群落中的地位和作用以及彼此间的竞争关系。结果表明: 狭穗草、叶背红色型五唇兰和毛俭草在该层占据较大的重要值。叶背红色型五唇兰较叶背绿色型具有更广的生态位宽度; 拟金草和叶背红色型五唇兰以相似的生态位宽度值居该层物种生态位宽度的首位。两种生态型五唇兰均与该层其他大部分物种具有较大生态位重叠值,两者间的生态位重叠亦很大。这说明五唇兰对其生境有很好的适应性,两种生态型间可能存在较大的竞争。

Abstract:

Phalaenopsis pulcherrima,an endemic orchid plant species in East Asia,presents two ecotypes which are characterized by green and red on the leaf dorsal side under natural conditions. Niche breadth and niche overlap of plant species in herb layer of P. pulcherrima communities in Bawangling Nature Reserve of Hainan Island were investigated for the position and relationship of the two ecotypes. The results indicated that Garnotia patula,P. pulcherrima and Mnesithea mollicoma had biggish important values in this layer. Niche breadth of Hedyotis consanguinea and Phalaenopsis pulcherrima with red dorsal are the greatest. Moreover,P. pulchrrima with red dorsal had higher value in niche breadth than P. pulcherrima with green dorsal. The niche overlap between P. pulcherrima and most of other species were great. High niche overlap was also showed between the two ecotypes of P. pulcherrima. These findings suggested that both ecotypes of P. pulchrrima were highly adapted to the local habitat,while competition between these two ecotypes might be potentially high.