毛竹林下多花黄精种群生长和生物量分配的立竹密度效应

Population growth and biomass allocation of Polygonatum cyrtonema within a Phyllostachys edulis forest utilizing bamboo density treatments

为优化出毛竹Phyllostachys edulis-多花黄精Polygonatum cyrtonema复合经营的立竹密度,以立地条件基本相似的3种立竹密度D1(1 500～2 500株.hm-2),D2(2 500～3 500株.hm-2),D3(3 500～4 500株.hm-2)的陡坡地粗放经营毛竹林为对象,调查分析了不同立竹密度毛竹林下多花黄精种群生长状况和生物量积累与分配规律。结果表明:毛竹林立竹密度对多花黄精地径、叶片叶绿素值和各构件生物量分配比例影响不明显,而对多花黄精种群密度、株高、各构件生物量和总生物量积累有一定的影响,均随着立竹密度的增大而减小。不同立竹密度毛竹林下的多花黄精生物量分配格局均为地下块茎>根、叶、地上茎,地下块茎生物量分配比例占70%以上,显著大于生物量分配比例差异不明显的其他器官(P<0.05)。立竹密度是影响毛竹林下多花黄精种群生长的重要因素,在试验毛竹林立地条件和经营水平情况下,毛竹-多花黄精复合经营适宜的立竹密度为1 500～2 500株.hm-2。

To optimize bamboo density for compound management of Polygonatum cyrtonema within a Phyllostachys edulis bamboo forest,population growth conditions,biomass accumulation,and allocation rules of Polygonatum cyrtonema at three different bamboo densities（1 500-2 500,2 500-3 500,and 3 500-4 500 stems· hm-2） in extensively managed Phyllostachys edulis stands with similar site conditions were studied.One-way ANOVA showed that for Polygonatum cyrtonema,population density,height,and biomass accumulation of each component as well as total biomass accumulation within bamboo density of 1 500-2 500 stems·hm-2 were significantly greater（P＆lt;0.05） than them in the other two bamboo densities;whereas no effect on diameter, leaf chlorophyll values,or biomass allocation ratio of each component was realized.Distribution patterns of Polygonatum cyrtonema showed that biomass allocated to underground tubers was significantly greater（P＆lt;0.05） than biomass of the sum of roots,leaves,and above stem grounds.Thus,bamboo density was the important factor affecting population growth.And for compound management of Polygonatum cyrtonema in Phyllostachys edulis stands with these site conditions,1 500-2 500 stems·hm-2 was best.