黄土高原灌丛对人工油松幼树生长的影响  

Effects of shrubs on the growth of saplings of Pinus tabuliformis plantations on the Loess Plateau

作　　者：韩兵兵[1] 王孝安[1] 李静[1] 王丽娟[1] 原志坚 

机构地区：[1]陕西师范大学生命科学学院,西安710119

出　　处：《生态学杂志》2016年第12期3197-3204,共8页Chinese Journal of Ecology

基　　金：陕西师范大学中央高校基本科研业务费专项(GK201603069)资助

摘　　要：为探讨灌丛对人工油松幼树生长的影响,以黄土高原灌丛边缘、灌丛中和砍伐释放区3种生境中的9年生同龄油松(Pinus tabuliformis)幼树种群为研究对象,分析了人工油松幼树的冠形特征以及当年主干、枝条和针叶的生长状况。结果表明:(1)人工油松幼树的株高在灌丛边缘、灌丛中和砍伐释放区间差异不显著,冠幅、树冠率、着生绿叶年限、基径表现为灌丛边缘>砍伐释放区>灌丛中,而枝下高与其相反。幼树的冠形特征在砍伐释放区与灌丛中差异不显著。(2)高出灌丛的油松幼树当年生长量与灌丛边缘个体差异不显著;当人工油松幼树低于灌丛时,灌丛不利于油松幼树当年主干及枝叶的生长;砍伐释放(人工抚育措施)减小了灌丛对油松幼树生长的不利影响。(3)灌丛中的油松幼树通过对树冠下层枝叶的自然整枝来减少不必要的营养消耗,进而改变植株的冠形特征。(4)当灌丛对人工油松幼树产生遮阴效应时,幼树将大部分干物质用于主干和枝条长度的生长,在枝条水平上增大叶的生物量比例,增大比叶面积,以适应弱光环境。In order to explore the effects of shrubs on the growth of 9-year-old saplings of Pinus tabuliformis on the Loess Plateau, the saplings were planted in 3 types of habitats： the edge of shrubs, the central of shrubs and shrub-cutting release area. The characteristics of crown shapes and the growth conditions of current-year trunk, branch and leaf of samplings were compared. The results showed that the tree height was not significantly different among the 3 habitats. The crown width, living crown ratio, the duration years of green leaves in the branch, basal diameter of the saplings all changed with the same pattern across the three habitats, being ranked as the edge of shrubs 〉 shrub-cutting release area 〉 the central of shrubs ; however, the height under branch showed an opposite pattern among habitats. The crown shapes did not differ between the central of shrubs and shrub-cutting release and leaf of P. tabuliformis was affected by area. The growth of the current-year trunk, branch shrubs only when the saplings were lower than the shrubs. The negative effects of shrubs on the tending measures in the shrub-cutting release self-pruning. They would take some bionomic were shaded by the shrubs, such as allocating growth of such saplings were alleviated by forest area. The saplings changed their crown shape by strategies to adapt to the environment when they more biomass to the growth of length than to the growth of diameter in current-year trunk and branch, increasing leaf biomass proportion at the branch level, and increasing specific leaf area.

关 键 词：黄土高原 油松幼树 灌丛 砍伐释放区 遮阴 

分 类 号：S791.254[农业科学—林木遗传育种]