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对广东省英德县桥头镇低丘台地上，初植密度为１２３０株／ｈｍ２的７年生火炬松人工林进行了不同间伐强度的试验，间伐２年后的结果表明：不同间伐强度对火炬松人工林的胸径、树高、单株材积和单位面积蓄积量均有极显著影响，对单位面积蓄积总量则无显著影响。强度和中度间伐均能极显著地提高胸径、树高和单株材积生长量；弱度间伐能极显著地提高树高生长量，显著提高胸径和单株材积生长量；强度间伐和中度间伐区间的胸径、树高和单株材积生长量差异均不明显；弱度间伐和对照区的单位面积蓄积量均极显著高于强度间伐区，弱度间伐区的单位面积蓄积量显著高于中度间伐区，中度间伐区的单位面积蓄积量显著高于强度间伐区，中度、弱度间伐区与对照区间的蓄积差异均不明显；间伐强度越大，伐后２年火炬松的胸径、树高、单株材积和单位面积蓄积量的增长率也越大。强度、中度、弱度间伐２年后大径木增加的比例分别比对照大１３％、１８．２５％、８．２５％。
The experiment of different thinning intensities of 7-year-old Pinus taeda plantations with initial planting density of 1230 plants / hm2 was carried out on the platform of low hill in Qiaotou Town, Yingde County, Guangdong Province. The results of two years after thinning showed that the effects of different thinning intensities on loblolly pine The DBH, tree height, single plant volume and unit area volume of plantation all had extremely significant effects, but had no significant effect on the total volume of plantation. Intensity and moderate thinning can significantly increase the DBH, tree height and volume per plant. The thinning can significantly increase the tree height growth, significantly increase the DBH and single plant volume growth; There was no significant difference in DBH, tree height and volume per plant between the thinning intervals. The stock volume per unit area in the thinning and control areas was significantly higher than that in the thinning area, and the stock volume per unit area in the thinning area was significantly higher than that in the thinning area The middle-thinned area and middle-thinned area had a higher accumulation per unit area than that of the middle-thinning area, but there was no significant difference in the middle-thinning area and the control area. The growth rate of DBH, tree height, single plant volume and unit area volume also increased. After 2 years of thinning, the proportion of large-diameter wood increased by 13%, 18.25% and 8.25% respectively compared with the control.