不同间伐措施对辽东栎幼苗自然更新及生长状况的影响

Effect of thinning on natural regeneration and growth of Quercus wutaishanicasaplings

【目的】研究间伐强度对辽东栎幼苗自然更新及生长的影响,为辽东栎林间伐经营与伐后管理提供依据。【方法】通过对黄土高原地区辽东栎林固定样地连续4年的调查,以封育为对照,研究间伐强度分别为13.4%（弱度间伐）和30.0%（强度间伐）的近自然经营林地中,辽东栎不同起源幼苗（实生苗、茎萌苗和根蘖苗）的自然更新与生长状况。【结果】不同起源辽东栎幼苗的年龄大致相同,随着年龄增加,幼苗数量逐渐下降;实生苗比萌生苗多,只有20%~45%的幼苗起源于根蘖苗或茎萌苗,伐后样地中的实生苗密度显著大于封育样地,而根蘖苗与茎萌苗密度在不同样地间无显著差异;调查期间,实生苗个体存活率最低,茎萌苗次之,根蘖苗最高;间伐林地内幼苗每年的高生长量大于封育林地;茎萌苗、根蘖苗的生长速度快于实生苗。【结论】在黄土高原地区,无论在间伐林地还是在封育林地,辽东栎种群均能够自然更新,但在不同经营措施中,辽东栎存在实生苗与萌生苗2种繁殖策略的权衡;近自然经营条件下,13.4%的间伐强度更有利于辽东栎群落实生苗的生长与更新;辽东栎的伐前更新是很重要的更新方式之一。

【Objective】 In this paper,the effect of thinning intensity on natural regeneration and growth of Quercus wutaishanica saplings was studied to provide a reference for cutting operation and management after felling of Q.wutaishanica forest.【Method】 The natural regeneration and development status of true seedlings,stem sprouts,and root sprouts saplings of Q.wutaishanica were investigated during 4 successive years on permanent plots of close-to-natural plantation thinning to 13.4% stocking（light thinning）,30.0% stocking（heavy thinning） and closed tending sites（CK） in the central China Loess Plateau.【Result】 The age of Q.wutaishanica saplings from different originations were similar.With the increase of saplings age,the saplings quantity decreased.The quantity of true seedling was more than that of sprout seedling.Approximately 20%-45% saplings were originated from root or stem sprouts.Seedling density was higher in thinning plot than that of block foster site,while the density of root and stem sprouts didn＇t show significant difference among three treatments.During the study period,the survival rate of root sprout was the highest,the stem sprout the second,and the true seedling the lowest.The saplings growth rate was higher in thinning plots than that of closed tending sites.Root and stem sprouts seedlings growth rate was higher than that of true seedlings.【Conclusion】 Whether in thinning stands,or in closed tending woodland,Q.wutaishanica saplings were abundant.It suggests that Q.wutaishanica can successfully regenerate.Q.wutaishanica existed with two breeding strategies between seedlings and seedling sprouts among different tending practices.Close-to-natural plantation thinning to 13.4% stocking was more advantageous to natural regeneration and growth for Q.wutaishanica seedlings.Vegetative regeneration was an important mode of post-logging regeneration.