中文摘要：

在科尔沁沙地证明低覆盖度行带式固沙林具有显著的防风效果后,进一步对雨养条件下杨树（赤峰-36号）固沙林的密度、配置及林木生长过程与林龄的动态关系进行研究。结果表明：1）1～5a林木的生长基本不受密度的影响,密度大单位面积材积量大;6～11a是密度对林木生长的显著影响阶段,杨树固沙林的胸径、株高和材积量的增长率随林龄增大而逐年加快;大约在11a之后趋于稳定;单位活立木蓄积最大（153.39m^3.hm-2）的固沙林密度是825株·hm^-2,其他密度按蓄积大小排序依次为540株·hm^-2、420株·hm^-2和1215株·hm^-2;2）边缘林木的平均胸径和单株材积量分别比林内高20%～70%和90%～260%,且低密度林分的边缘林木的生长优势比高密度林分边缘林木的生长优势更加明显;3）同密度（500株·hm^-2）13a的一行一带式固沙林,其胸径、树高和材积量分别比等株行距的片林高37.4%、17.4%和81%;而10a的两行一带式的胸径、树高和材积量分别比等株行距的片林高19.8%、16.2%和64.8%,说明行带式配置还具有生物生产力优势。

英文摘要：

Research on the dynamics between the density,planting composition,average DBH,height,canopy width,tree volume,forest volumes,and the changes through the growth of the stand of a natural rain-fed,sand-fixing,Chifeng-36 poplar forest in Horqin sandy land of dry sub-humid climate reveals that：1）Planting density shows no discernable effect on the growth of 1～5-year-old stands.Densification of the stand will effectively increase the forest volume per hectare.When stands enter 6～11 years of age,the effect of planting density on the forest growth starts to mount,in that the growth rates of the DBH,height,and timber volume will expedite as the stands age.At age 11 and above,such effect appeases.Among the all stands involved in the experiment,the volume reaches the maximum（153.39 m^3·hm^-2）with a stand of 825 stems·hm^-2.The volume decreases as the forest density changes from 540 stems·hm^-2 to 420 stems·hm^-2 and minimizes at 35.18 m^3·hm^-2 with a density of 1 215 stems·hm^-2.2）The average DBH and the timber volume of single plant along the stand edge are 20%～70% and 90%～260% higher respectively than those at the forest core.Moreover,the growth along the stand edge is even more remarkable when the stand has a low density.3）Holding constant the density at 500 stems·hm^-2,the DBH,height,and timber volume of a 13-year-old,one-row-and-one-belt sand fixation forest are 37.4%,17.4% and 81% higher than those of a evenly planted stand,respectively.The same measurements of a 10-year-old,two-row-and-one-belt sand fixation forest will be 19.8%,16.2% and 64.8% higher than a evenly planted stand,respectively.