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为探索适宜大小的林窗改造模式,在川中丘陵区高密度的柏木人工纯林中,选择人为砍伐形成的不同大小林窗样地36个,研究光热环境、植物生长和多样性随林窗大小的变化.结果表明:疏伐后,林窗内光合有效辐射和气温显著升高(P<0.05),空气湿度和土壤相对含水量显著降低(P<0.05),光合有效辐射和气温随林窗面积的增大而增加,空气湿度和土壤相对含水量随林窗面积的增加而降低.疏伐后,林窗内乔木高度、胸径、郁闭度和冠幅较未疏伐对照样地更新层显著提高(P<0.05),灌木高度和盖度、草本层盖度和枯落物层厚度显著提高(P<0.05),单位面积柏木蓄积量和单株柏木材积较未疏伐对照样地更新层显著增加(P<0.05),不同林窗大小之间,植物生长指标随面积的增加呈单峰型变化,峰值出现在90-110 m2林窗内.疏伐后,林窗内植物种数、属数和科数增加,乔木、灌木和草本种数增多,物种丰富度指数和多样性Shannon-Wiener指数显著提高(P<0.05),中林窗内植物区系组成最复杂,植物物种多样性最丰富.林窗和非林窗植物共有种为6-9种,相似系数在30.43%-36.73%之间.可见林窗式疏伐促进了林下植物的更新,90-110 m2的中林窗效果更为明显.
In order to explore the appropriate size of the forest window reconstruction model, in the high density of Kashiwagi Artificial pure Hilly in Central Sichuan, choose 36 different sizes of forest window cutting by artificial cutting, to study the light and heat environment, plant growth and diversity with the gap (P <0.05), air humidity and soil relative water content decreased significantly (P <0.05), photosynthetically active radiation and temperature with the forest The window area increased and the air humidity and soil relative water content decreased with the increase of the forest window area.After thinning, the tree height, DBH, crown closure and crown width in the gap were updated (P <0.05). The shrub height and cover, herb layer cover and litter layer thickness increased significantly (P <0.05). The accumulation of cypress per unit area and cypress area per plant were significantly higher than those of the control (P <0.05). The index of plant growth varied with the increase of area and the peak appeared in the gaps of 90-110 m2. After thinning, The number of genus and genus increased, and the number of trees, shrubs and herbs increased The Shannon-Wiener index of richness index and diversity increased significantly (P <0.05), and the flora of Zhonglin window was the most complex with the most abundant plant species diversity. There were 6-9 species , Similar coefficient between 30.43% -36.73% .From the canopy gap thinning to promote the regeneration of understory plants, 90-110 m2 Zhong Lin window effect is more obvious.