【摘要】 本文以两个生长季的调查测定为基础．分析了松嫩平原碱化草甸天然碱地肤种群不同数量性状的密度制约规律及其数量调节机制。两个生长季取样合并拟合的幂函数模型，是碱地肤种群平均植株重、平均植株籽实重、单位面积籽实重、籽实重比率以及在籽实成熟期的地上生物量等性状密度制约的最好描述模型。综合分析的结果表明，环境容纳量随环境条件而变化，在环境容纳量和密度制约上，两个生长季均表现为籽实成熟期比开花期大。密度制约作用是一个连锁反应过程，碱地肤种群最终是以增减对生殖生长能量分配的生殖对策来实现其种群的数量调节。更多还原

【Abstract】 Kochia sieversiana is an alkali-tolerant annual herb belonging to Cheno- podicccae. Based on data measured in tow growing seasons,the density-depe-ndent rule of different quantitative characters and the mechanism of quanti- tative regulation on the natural population of K. sicversiana in the alkaline meadow in tlie Song-Nen Plain of China were analysed in this paper. The mergence equations of power function that were simulated by sampling twogrowing seasons were the best descriptive models describing the density-depe-ndence of the population characters,including mean weight per plant, mean fruit weight per plant, fruit weight per unit area,fruit weight/above-ground biomass ratio in the ripening stage.The results of our comprehensive analvsis showed that the carrying capacity of environment varied with habitat condi-tions,and that both the carrying capacities of environment and the effects of density-dependence were larger in the ripening stage than in the flowering stage in the two seasons.The effcct of density-dependence was a process of chain reaction。The population regulation was lastly realized by reproductive strategies which increased or lessened energy allocation to the reproductive growth.更多还原