两个生态型羊草种群的营养更新特征分析

在西辽河平原天然羊草草地上取样研究了灰绿型和黄绿型两个羊草种群分株的数量特征．结果表明，地上分株生物量、新世代无性分株生物量和新世代有性分株生物量存在显著差异，再生世代分株生物量没有显著差异，分株生物量分配均以新世代分株、无性分株占优势；反应种群营养更新特征的种群新生系数和种群再生系数两个生态型分别为0.63，0．37和0.57，0．43没有显著差异．羊草两个生态型在种群结构相对稳定期有趋异适应方式，又有相似的适应规律。

Analysis of Vegetative Renovation Characters on Two Ecotypes of Leymus Chinensis Population

Leymus chinensis(Trin.) Tzvel.is a perennial rhizome grass with two ecotype grey-green type and yellow-green type. Quantitative character of ramets was analyzed by sampling in the natural grassland of the Xiliao River Plains. The result showed that biomass of ramets, biomass of new generation vegetative ramets and biomass of new generation reproductive ramets had significantly different on the two ecotypes. Biomass of regenerative ramets had no significantly different. New generation ramets and vegetative ramets were dominant rate in biomass allocations. Population vigorous coefficient and population preservable coefficient played a great role in manifesting vegetative renovative characters of population. Population vigorous coefficient of grey-green type and yellow-green type were 0.63 and 0.57, while population preservable coefficient was 0.37 and 0.43. The two ecotypes demonstrated divergent adaption and similar adaption regulation simultaneously in stable stage of population structure.