种植密度对桉树苗生物量分配的影响

Effect of Planting Density on Biomass Allocation of Eucalyptus Seedlings

为研究种植密度对桉树苗生物量分配的影响,以3月龄尾巨桉无性系DH32-29生物质能源组织培育苗为研究对象,对比分析了低、高种植密度下桉树苗的发育性状、生物量及其分配情况。结果表明:低种植密度下,桉树苗的基径、冠幅、冠长以及生物量均显著增加,基径提升约26.3%、基径月发育量提升约67.8%、冠幅与冠长分别提升约56.2%、28.2%,差异性水平显著;差异种植密度的叶、枝、茎在0.05水平上差异显著,跟随种植密度的增大,其生物量均呈减少态势;低种植密度下,枝的生物量占比为22.2%、叶的生物量占比为19.3%、茎的生物量占比为58.5%,枝、叶的生物量跟随种植密度的增加均呈降低态势,茎呈升高态势,表示种植密度会对桉树苗各部分生物量的分配情况造成一定影响,综合表明:种植密度能够较好地调控桉树苗的所有发育性状,较低的种植密度更有利于桉树苗的发育。

In this study,the effects of planting density on biomass allocation of Eucalyptus grandis seedlings were studied,and the development characters,biomass and biomass allocation of Eucalyptus grandis seedlings were compared and analyzed under low and high planting density.The results showed that the basal diameter,crown width,crown length and biomass of Eucalyptus seedlings increased significantly under low planting density.The basal diameter increased by 26.3%;the monthly growth of basal diameter increased by 67.8%,and the crown width and crown length increased by 56.2%and 28.2%,respectively.Leaf,branch and stem with different planting densities had significant differences at the 0.05 level,and their biomass decreased with the increase of planting density.At low planting density,the biomass of branches,leaves and stems was 22.2%,19.3%and 58.5%,respectively.The biomass of branches and leaves decreased with the increase of planting density,while the biomass of stems increased,indicating that planting density would have a certain effect on the biomass allocation of each part of Eucalyptus seedlings.The results showed that planting density could regulate all developmental characters of Eucalyptus seedlings better,and lower planting density was more favorable to the development of Eucalyptus seedlings.