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【目的】探索不同间伐强度对阴坡、阳坡栓皮栎林木生长及干形的影响,为栓皮栎林的合理抚育间伐和经营提供依据。【方法】以秦岭南坡商洛地区阴坡、阳坡生长的栓皮栎次生纯林为研究对象,设置不同间伐强度(弱度、中度、强度间伐分别保留郁闭度为0.8,0.7和0.6)和对照(未间伐)样地各3块,每块样地面积20m×20m,于抚育间伐7年后对不同间伐强度下林木的生长、干形进行调查比较。【结果】阴、阳坡两种生境条件下,栓皮栎胸径、冠幅、单株胸高断面积、单株材积现存量均与间伐强度成正相关关系,间伐7年后林分胸高断面积、蓄积均下降,间伐强度对树高的影响不显著;两种坡向的林木胸径、树高、冠幅年均生长率均表现为冠幅年均生长率>胸径年均生长率>树高年均生长率;间伐后,两种坡向的林木平均通直度均提高,阴、阳坡林木平均通直度分别在中度、弱度间伐时最高,高径比、活枝下高有所降低,而栓皮栎林平均分杈率出现先下降后升高的趋势,阴坡的平均分杈率小于阳坡。【结论】间伐强度对不同坡向栓皮栎林木生长、干形的影响存在差异,强度间伐(保留郁闭度0.6)对两种坡向林木生长的促进效果最好;弱度间伐(保留郁闭度0.8)较利于阳坡培育优质干形,而中度间伐(保留郁闭度0.7)较利于阴坡培育优质干形;对林分进行抚育间伐时,应考虑培育目标以及林木的生境条件,以便在更好地促进林木生长的同时获得更多的经济效益。
【Objective】 The objective of this study was to explore the effects of different thinning intensities on the growth and dryness of Quercus variabilis forest on the shady and sunny slopes, and provide the basis for reasonable tending and thinning of Quercus variabilis forest. 【Method】 The secondary cuttings of Quercus variabilis grown on shady slopes and sunny slopes in the Shangluo area on the southern slope of Qinling Mountains were used as research objects, and different thinning intensities were set (weakness, moderate and strong thinning respectively reserved canopy density of 0.8, 0.7 and 0.6 ) And control (no thinning) plots, each with an area of 20m × 20m. After 7 years of tending and thinning, the growth and dryness of the trees under different thinning intensities were investigated and compared. 【Result】 The results showed that there was a positive correlation between the DBH and crown width, the area of chest height of single plant and the stock volume of single plant under the two habitats of Yin and Yang slope. After 7 years of thinning, the area of chest height and the area of accumulation But the effect of thinning intensity on tree height was insignificant. The DBH, tree height and crown average annual growth rate of the two slopes showed that the annual average growth rate of crown width> the average growth rate of DBH> the annual average height of tree height Growth rate. After thinning, the average straightness of trees in both directions increased, while the average straightness of trees in shade and sunny slope were the highest, the height-diameter ratio and the live branch height were lower , And the average bifurcation rate of cork oak forest first decreased and then increased. The average bifurcation rate of shady slope was less than that of sunny slope. 【Conclusion】 The effects of thinning intensity on the growth and dryness of Quercus variabilis were different in different slopes. Strength thinning (preserving canopy density 0.6) had the best effect on the growth of two types of slope trees; thinning (keeping canopy Degree 0.8) is more favorable to the cultivation of high quality dry-type on the sunny slope, while moderate thinning (keeping the canopy density 0.7) is more advantageous to the cultivation of high-quality dry-shaped on the shady slopes. When cultivating the stands, the cultivation objectives and the habitat conditions should be taken into account, In order to better promote the growth of trees at the same time get more economic benefits.