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为了阐明抚育间伐强度对辽东栎生殖构件的影响,以黄土高原南部黄龙和桥山林区辽东栎中龄林为研究对象,对不同间伐强度(对照、10%、20%、30%)下近自然经营抚育间伐5年后的辽东栎平均单株个体大小、生殖构件产量、比率及空间分布格局特征等进行研究.结果表明:间伐强度对辽东栎林分平均树高、胸径影响不显著,而与冠幅面积、冠幅体积呈显著正相关;辽东栎标准株的生殖枝、幼果、成熟果实产量随间伐强度的增大而增大,而营养枝、雄花序、雄花、雌花的产量变化不大.当间伐强度达到20%时,生殖枝、幼果、成熟果实产量显著提高,30%间伐下达到最大.生殖枝比例和座果率随间伐强度增大而增大,在20%、30%间伐强度时与对照的差异达到显著水平.约3/4的生殖枝、雌花、雄花集中分布于树冠上层,1/4分布于下层;树冠阳面生殖构件数量占65%,树冠阴面占35%.树冠下层、阴面生殖枝、雌花、雄花序的空间分布比例随着间伐强度的增大而增大;树冠上层、阳面生殖枝、雌花、雄花序分布比例随间伐强度的增大呈递减趋势.因此,选择30%间伐强度(保留郁闭度0.6)最佳,可以大幅提高辽东栎的座果率和成熟率,有效提高结实量和品质,为辽东栎林的采种及天然更新提供保证.
In order to clarify the effect of tending thinning intensity on the reproductive components of Quercus liaotungensis, the middle-aged stands of Quercus liaotungensis in Huanglong and Qiaoshan Mountains in the southern loess plateau were used to investigate the effects of tending on the reproductive components of Quercus liaotungensis. The average individual plant size, reproductive component yield, ratio and spatial distribution pattern of Quercus liaotungensis in five years after tending were studied.The results showed that the thinning intensity had no significant effect on the mean tree height and DBH of Quercus liaotungensis, Crown area and crown volume. The yield of reproductive branch, young fruit and ripe fruit of Quercus liaotungensis increased with the increase of thinning intensity, while the change of yield of vegetative branch, male inflorescence, male flower and female flower was not When the thinning intensity reached 20%, the yield of reproductive branch, young fruit and ripe fruit increased significantly, reaching the maximum under 30% thinning.The proportion of reproductive branch and fruit set increased with the thinning strength increasing at 20%, 30 The percentage of reproductive branch, female flower and male flower of about 3/4 were concentrated in the upper canopy, and 1/4 in the lower layer. The number of male reproductive canopy accounted for 65%, the canopy negative 35% Under the canopy , And the proportion of female reproductive branch, female flower and male inflorescence increased with the increase of thinning intensity. The proportion of reproductive branch, female flower and male inflorescence in the upper canopy increased gradually with the increase of thinning strength. Therefore, 30% thinning intensity (preserving canopy density 0.6) is the best, which can significantly increase the fruit set rate and maturity of Quercus liaotungensis, effectively increase the yield and quality, and provide the guarantee for the seed collection and natural regeneration of Quercus liaotungensis.