林缘与林内生境中黄花杓兰生态适应性研究

Ecological Adaptation of Cypripedium flavum at Forest Edge and in Forest

黄花杓兰(Cypripedium flavum)为中国特有的兰科植物,喜生于疏林下。生境破碎产生大量的生境边界,喜光杂草、先锋树种的侵入形成荫蔽环境不利于黄花杓兰的生存。对香格里拉处于林内与林缘两种生境中的黄花杓兰植株进行了研究,探讨生境破坏产生的边缘生境对黄花杓兰种群生存的影响。研究发现林缘植株叶片长、叶鲜质量、比叶面积等指标小于林内植株并具有统计学意义(p<0.05),林缘植株株高、叶面积小于林内植株但不具有统计学意义;叶片数、叶片干物质含量显著高于林内植株,林缘植株叶绿素相对含量、叶片宽高于林内植株但不具有统计学意义。林内植株的花部形态指标中,除唇瓣开口宽外,其他均较林缘的大,表明林内植株在积极适应弱光照环境,但林内植株的座果率比林缘的低、幼龄植株个体少,表明林内荫蔽环境影响到黄花杓兰种群更新与生殖过程。研究认为对该植物应该加强生境的保护。

Cypripedium flavumis an orchid endemic to China,and prefers to grow in sparse forest.Habitat fragmentation can produce lots of edge,then photophilous weeds and pioneer trees invade the edge,which leads to shade environment and does harm to the survival of C.flavum.This article aims to study the edge effect on the individuals at the edge and in the forest.The results show that leaf length,leaf fresh weight,and specific leaf area in the forest are significantly smaller than that at forest edge,and the height and leaf area are smaller in forest than that at forest edge without significant level.Leaf number and leaf dry material content at the edge are significantly higher than that in the forest;Chlorophyll relative content and leaf width at forest edge are higher than that in the forest without significant level.The flower characters except the labellum width in the forest are bigger than that at the edge,but the difference is not significant,which indicates the individuals in the forest try to adapt to the low light environment.The fruit rate is zero for two years in the forest,and the number of seedlings is very scarce compared with that at the edge,which means that the shade environment under the forest affects population reproduction and regeneration.The habitat of this plant should be protected from fragmentation and loss.