习水特有极危植物吴氏石山苣苔种群结构和叶面积特征

Population Structure and Leaf Area Characteristics of Critically Endangered Plant Petrocodon Wui Endemic to Xishui

摘要: 为了理解贵州省习水国家级自然区特有极危植物吴氏石山苣苔的生物学和生态学特性，调查了该物种的种群结构特征，基于无损方法建立了该物种的叶面积模型。结果表明：吴氏石山苣苔目前处于极小种群和极危状态；该物种兼具有性和无性2种繁殖方式；由于适应特殊的陡峭岩壁生境，该物种中下部的茎发展出了贴着岩面向下俯垂生长的特殊习性；该物种的植株常具有宿存的枯叶，但枯叶数量不与其龄级呈显著的正相关性；幂函数能很好反应该物种叶面积与叶片长和叶片宽乘积之间的关系，且单株叶面积和叶柄长都有波动着向上减少的趋势。吴氏石山苣苔亟需通过人工快繁的方法来增加个体数量，进行迁地保护；如能通过人工快繁获得生长良好的植株，还可以进行野外回归，扩大该物种在原产地的种群和个数数量。

Abstract: In order to understand the biological and ecological characteristics of the critically endangered plant Petrocodon wui endemic to Xishui National Nature Reserve in Guizhou Province, the popula-tion structure characteristics of this species were investigated, and a leaf area model of this species was established based on non-destructive methods. The results indicate that this species is cur-rently in a very small population and extremely dangerous state. This species has both sexual and asexual reproductive modes; due to adapting to the unique steep rock habitat, the stems in the middle and lower parts of this species have developed a special habit of growing downwards against the rock surface; individuals of this species often have persistent withered leaves, but the number is not significantly positively correlated with their age class; a power function can well reflect the relationship between the leaf area of this species and the product of leaf length and leaf width, and both the leaf area and petiole length of a single plant show a fluctuating upward decreasing trend. P. wui urgently needs to increase its individual quantity through artificial rapid propagation for ex situ protection; if well-growing plants can be obtained, field regression should also be carried out to expand the population and number of the species in the original area.