白桦林下红松人工更新技术的研究

ARTIFICIAL REGENERATION TECHNIQUES FOR KOREAN PINE UNDER WHITE BIRCH FOREST

对30多年生的白桦林实行疏、皆伐后,光照、气温和土温明显提高,相对湿度降低。白桦林皆伐后,灌木、草本植物种类增加,盖度增大,白桦伐根萌生幼树大量出现,影响了红松人工更新幼树的生长,增加了幼林抚育的难度。白桦林疏伐后,促进了保留木的生长,蓄积生长率为对照区的2.64倍。白桦林疏伐后进行红松人工更新,3a后保存率高达92.9％,而皆伐区只有54.5％。林冠下红松人工更新有效地避免了皆伐迹地上幼树的蹲苗现象,更新7a后幼树主要生长指标仅略低于皆伐区,但幼树生长良好,色泽翠绿,无早期分叉现象,适时疏伐上层阔叶树,红松幼树的生长将迅速加快,形成以红松为主的针阔叶混交林。

Light intensity, air temperature and soil temperature increased significantly after thinning and clear cutting a 30—year—old forests. But, the relative moisture decreased. Species numbers of herbs and shrubs increased after clear cutting, which influenced growth of artificially regenerated Korean pine saplings and brought difficulties for tending. The growth of Korean pine saplings increased after thinning the birch forest. Volume growth increased by 2.64 times of the control. The survival rate after three years for Korean pine regenerated artificially is 92.9% under the white birch forests thinned and 54. 5% on clears. Growing parameters of 7-year-old Korean pine saplings slightly decreased under birch canopy, but they grew very well and had no forking. Korean pine saplings would grow quickly and form a mixed broadleaved/Korean pine forest if above canopy tree were thinned properly.