【摘要】 通过人为控制种群密度的栽培实验，从基株和构件水平上观察羊草无性系种群的生长动态，分析不同密度水平上羊草种群通过调节种群的生长、发育、增殖以及死亡过程来适应密度制约的途径。研究结果表明：１）羊草种群密度可在不同的构件水平间得到调节。当基株密度得到适当调节后便可减缓构件密度（无性系枝条、根茎芽等）的变化幅度和影响构件的发育进程。２）无性系枝条是羊草种群的主体，常在生长季后期出现大量增长，都处于生长旺盛的幼苗期，为翌年春季的返青积累能量和物质。３）单位面积总生物量随密度增加而提高，虽然尚未出现产量恒值现象，但存活枝条平均单株重（地上生物量）随密度增加呈下降趋势，这已反映出密度制约的作用。４）不同密度下羊草种群的生殖过程表现为：低密度时以无性繁殖为主，根茎芽的存活力较高；高密度时以有性繁殖为主，生殖分配值较大。更多还原

【Abstract】 The influence of Leymus chinensis population density on growth dynamics at modular level was investigated.The correlation between density and growth dynamics of single experimental　L.chinensis was analyzed.The results were as follows:① Genet’s density influenced ramet’s density and developmental process.Adjusting genet population density can narrow the variation range of ramet density.② The population biomass increased as density increase,but it did not come to a constant value.But the biomass per genet began to decrease as density became bigger.③ Under low density,vegetative propagation dominated and survival capacity of rhizome buds was high while sexual reproduction dominated and the reproduction allocation value was big under high density.更多还原