Abstract: In this paper, the bioecological characteristics of 7 populations of Allium wallichii in Jizu Mountain were systmatically analyzed. There were diploid 2n= 2x= 14) and tetraploid (2n=4x=28) observed in the species Allium unllichii Kunth in Jizu Mountain. The habitats of diploid population are constant and barrener, which restricts the intrusion of tetraploid plants. No obvious differentiation existed between diploid population. Tetraploid populations' habitats are various, and the differentiation in niche, morphology and phenology between the population are significant. The diploid plants can't stand the shortage of light in forest, however, on the grassland and the rocks, the dwarf diploid plants have no capacity to compete with tetraploid plants and grass, so the diploid also couldn't intrude into the habitats of tetraploid plants. The dominant ecological factors causing population differentiation are light, soil and biotic factors. However,the water factor is the restricted factor which is the distributing underline of Allium wallichii in Jizu Mountain.

Key words: Jizu Mountain

摘要： 对鸡足山地区7个多星韭（Allium wallichii Kunth）种群的生物生态学特性进行了比较全面的研究。结果表明：鸡足山地区的多星韭有二倍体和四倍体2种倍性。多星韭二倍体比四倍体更能忍受较恶劣的环境条件。二倍体多星韭生境单一，种群分化不明显；四倍体多星韭生境多样，种群间变异丰富，分化强烈。二倍体多星韭生境中土壤浅薄的条件限制了植株根深而高大的四倍体多星韭的侵人，而四倍体生境中，林内光照较弱、草坡杂草深而较密集等条件也限制了较矮小的二倍体多星韭的人侵。在鸡足山地区，水分是多星韭在该区分布下限的限制因子，光、土壤和生物因子是促使多星韭种群变异分化的主导因子。

关键词: 鸡足山, 多星韭, 主导因子, 生态因子, 种群分化