摘要
通过对辽东山区不同间伐强度下长白落叶松林内种子库,种子萌发,幼苗出现、成活与生长的观测,分析了长白落叶松天然更新的主要影响因素.结果表明:40年生落叶松人工林的种子雨中,有30%的种子有活力,可以满足天然更新的需要;土壤种子库的种子主要分布在枯枝落叶层,4月下旬林内种子开始萌发,6月幼苗数量达到最大,幼苗累计出现率与间伐强度(光照)之间无显著相关,只受到地被物的影响;随间伐强度的增加,幼苗平均存活率提高,但林下幼苗生长缓慢,苗高均不超过6 cm;林内当年幼苗9月全部消失,没有超过1年生的幼苗,但皆伐迹地的更新幼苗存活较多、生长良好.初步确定地被物和光照是辽东山区长白落叶松天然更新的主要障碍因子.
Based on the field investigations about the seed bank, seed germination, seedling emergence, and seedling survival and growth in the Larix olgensis plantations with different thinning intensities and various ground preparations in the montane regions of eastern Liaoning Province, the main factors affecting the natural regeneration of L. olgensis were analyzed in this paper. The results showed that in the seed rain of 40 years old L. olgensis plantation, 30% of the seeds had viability, which could meet the needs of natural regeneration. The seeds in soil seed bank mainly distributed in litter layer, and the seedlings younger than one-year old emerged in April and reached the peak in June. The accumulative emergence rate of the seedlings had no significant correlation with thinning intensities, but was affected by ground preparations. The average survival rate of appeared seedlings increased with increasing thinning intensities, but the seedling growth was generally slow in the plantation stands, e.g. , the seedling height was less than 6 cm, and most of the seedlings disappeared in September. In the plantation stands, it was difficult to find the L. olgensis seedlings elder than one-year; but in the clear-cut area with enough light and less ground cover, more seedlings could survive and grew well. Based on the above mentioned results, it was concluded that the main obstacles for the natural regeneration of L. olgensis plantations in montane regions of eastern Liaoning Province could be light intensity and ground cover.
出处
《应用生态学报》
CAS
CSCD
北大核心
2008年第4期695-703,共9页
Chinese Journal of Applied Ecology
基金
中国科学院百人计划项目
国家自然科学基金项目(30671669)
国家“十一五”科技支撑资助项目(2006BAD03A04,2006BAD03A09)
关键词
辽东山区
长白落叶松
人工林
天然更新
间伐
montane regions of eastern Liaoning Province
Larix olgensis
plantation
natural regeneration
thinning.
