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为了阐明抚育间伐强度对辽东栎林结实规律的影响,以黄土高原南部黄龙山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%)近自然经营抚育间伐5年后的林分密度与结实母树比例、平均单株结实与单位面积林分总结实量、种子在树冠上空间分布特征及种子特征等进行调查分析.结果表明:辽东栎林结实母树的比例、平均单株结实量及发育种子比例均随着间伐强度的增大而增大,表现为30%>20%>10%>对照;而单位面积林分总结实量在20%强度间伐时达到最大,表现为20%>30%>对照>10%.从辽东栎种子在树冠上的空间分布来看,73.6%的种子集中分布于树冠上层,26.4%分布于下层.树冠阳面结实量占总结实量的65.8%,树冠阴面仅占34.2%,间伐强度对树冠下层、阴面结实量的提升幅度分别大于树冠上层和阳面.辽东栎种子的长径、短径及千粒重均随间伐强度的增大而增大,在30%间伐强度时达到最大.10%强度间伐对辽东栎林结实影响不显著,间伐强度达到20%时,才能显著提高辽东栎种子的数量和品质,继续提高间伐强度到30%时,并不能有效提高其结实,而其林分总结实量却下降.建议在对该林区进行抚育间伐时,应选择20%的间伐强度(保留郁闭度0.7),可有效提高辽东栎种群的结实量和品质.
In order to clarify the effect of tending thinning on the law of seed setting of Quercus liaotungensis, the middle-aged stands of Quercus liaotungensis in Huanglong Mountain and Qiaoshan forest area in the southern Loess Plateau were used to study the effects of different thinning intensities (control, 10%, 20% and 30% Natural run stand density and strong mother trees Thinning ratio after five years, the average per plant and seed per unit area stand summed up the real, the spatial distribution of seed and seed characteristics such as investigation and analysis of the results showed that the canopy: Liaodong oak forest The proportion of sturdy mother trees, the average number of per plant and the proportion of developing seeds increased with the increase of thinning intensity, which was 30%> 20%> 10%> control; The spatial distribution of Q. liaotungensis seedlings on the crown of the canopy showed that 73.6% of the seeds were concentrated in the upper canopy and 26.4% in the lower canopy. The sturdy yield accounted for 65.8% of the total realizable value, while the canopy shade accounted for only 34.2%. The thinning intensity increased the density of undergrowth and shadeiness of canopy by more than that of the canopy, Increased strength When increasing the maximum .10% Thinning and Fruit of Quercus forest was not significant at the 30% thinning intensity, thinning intensity of 20%, in order to significantly improve the quantity and quality of seeds of Quercus, and continue to improve the thinning intensity to 30% , It can not effectively improve its sturdiness, but its total stand volume has declined.It is suggested that a thinning intensity of 20% should be selected when the thinning is carried out in this forest area (keeping canopy density 0.7), which can effectively increase Quercus liaotungensis The sturdy population and quality of the population.