【摘要】 在黑龙江省穆棱东北红豆杉自然保护区内,对10株天然东北红豆杉结实母树冠下的土壤种子库进行了调查分析。结果表明:东北红豆杉土壤种子库中的种子数量在垂直方向和水平方向上都表现出明显的规律性。在不同深度土层中的种子数量差异显著(p<0.05)。枯枝落叶层及0～5cm土层集中了最大量的种子,占总量的84%,随土层深度的增加,种子数量逐渐减少,15cm以下极少有种子出现。土壤种子库中具有活力的种子数量极少,不到总量的1%。种子丧失活力的首要原因是被昆虫和啮齿类动物啃食,占损失量的52%,其次是腐烂,占29%。在水平方向上,东北红豆杉种子具有近母株分布的特点,且在不同方向上种子数量差异极显著(p<0.01)。当年下落到地面的东北红豆杉种子,按远离母株的顺序,种子数量逐渐减少;在围绕母株的八个方向上,东向的种子数量最多,其次是东北、北和东南方向,西面的种子数量最少。当年下落的3%的完好种子补充到土壤种子库中。自然条件下,东北红豆杉以种子繁殖,土壤种子库是其自然更新及种群恢复的重要基础,本研究结果对于东北红豆杉濒危机制的探索及种群恢复具有重要的理论意义。更多还原

【Abstract】 We investigated and analyzed the soil seed bank under 10 female Japanese yew(Taxus cuspidata)trees in Muling Nature Reserve of Heilongjiang Province.The distribution of Japanese yew seeds in soil was consistent.Seed density declined with increasing depth of soil(p<0.05).Most seeds were in the litter layer and in the top 5 cm of soil(84%).There were almost no seeds at soil depths greater than 15cm.Viable seeds accounted for less than 1 percent of total seeds.The most important factors affecting Japanese yew soil seed bank were predation by insects and animals,accounting for 52% of total seeds,and decay,accounting for 29%.The seeds fall around the female tree when they are mature.Seed density declined with increasing distance from mother tree.Seed distribution varied with orientation(p<0.01),with most seeds to the north of the female tree,followed by northeast,north and southeast.Fewest seeds were recovered to the west of female trees.Over 3 percent of the total seeds on the ground were intact and recruited to the soil seed bank.The soil seed bank is important for reproduction of Japanese yew in nature.This research provides theoretical guidance for protection and restoration of the natural population of Japanese yew.更多还原