思茅松种子园疏伐强度探究

为探索思茅松种子园保留密度对生长量和球果产量的特性,对7年生相同家系的思茅松种子园开展5种不同疏伐强度(疏伐强度25%、疏伐强度30%、疏伐强度45%、疏伐强度50%和不疏伐)的疏伐试验,观测试验前、2年后的生长量(树高、胸径、冠幅)和球果数,计算出相应的增长量,对增长量进行方差分析。结果表明:5种不同疏伐强度2年后树高、胸径、冠幅和球果数增长量最大的处理均是疏伐强度为50%的处理,树高增长量次之的处理是疏伐强度为25%的处理,胸径、冠幅和球果数增长量次之的均是疏伐强度为42%的处理。树高、胸径、冠幅和球果数增长量小的处理均是对照CK。5种不同疏伐强度的树高增长量差异不显著,胸径、冠幅和球果数增长量差异均显著。该差异可作为思茅松种子园郁闭期保留密度依据之一。

Study on Thinning Intensity of Pinus kesiya Seed Orchard

In order to explore the effect of reserved density in seed orchard on growth and cone yield of Pinus kesiya,five thinning experiments with different thinning intensities(25%,30%,45% and 50% of thinning intensity and no thinning)were carried out in 7-year-old Pinus kesiya seed orchard with the same family.The growth(tree height,DBH,crown diameter)and cone number before and after the experiment were observed and calculated.The variance analysis showed that the highest increase of tree height,DBH,crown diameter and cone number after 2 years of five different thinning intensities was 50% thinning treatment,followed by 25% thinning intensity for tree height,42% thinning intensities for DBH,crown diameter and cone number,and the smallest was CK.There was no significant difference in height increment among five different thinning intensities,but significant difference in DBH,crown diameter and cone number increment,which could be used as one of the basis for planting density selection in Pinus kesiya seed orchard.