大兴安岭兴安落叶松天然林林隙地被物变化特征研究

Research on Characteristics of Vegetation Change in Gaps of Larix gmelinii Natural Forest in Daxinganling

根据在大兴安岭调查兴安落叶松天然林林隙结构,阐述了林隙地被物变化特征。结果表明:从林隙中心向外随着距林隙中心距离的增加,灌木高度和盖度呈先增加,后减小趋势。在林隙内,随着离林隙中心距离增加,灌木高度和盖度逐渐增加。越过林隙边缘进入林内后,灌木高度和盖度随着距离增加,又逐渐减小。灌木种数呈少-多-少的变化过程。在林隙边缘地带,灌木盖度最大、种类最多;从林隙中心到林内随着距离增加,草本高度、盖度、种数逐渐变小;随着林隙内枯倒木腐烂程度增加,林隙更新株数有增多趋势。更新株数随着林隙面积增加,总体上趋于减少,呈现单峰型变化;林隙内死地被物厚度比林内小。从林隙中心到林内,随着距离增加,藓类高度和盖度、死地被物厚度和盖度趋于增加。

This paper described the characteristics of vegetation change in gaps of Larix gmelinii natural forest in Daxinganling. Based on the data, it was concluded that as the distance gets farther from the center of a gap, the height and coverage of shrub decreased after the increase. That was, from the center of a gap toward the edge the height and coverage of shrub gradually increased, and beyond the gap to forest they gradually decreased. The number of shrub species had an altering process from little to much to little. At the edge of a gap the coverage and species of shrub were the greatest; as the distance getting farther from the center of a gap, the height, coverage and species of herbage decrease; with the litter of falling stem getting rot, the number of gap renovation increased. As the area of gap increased, the number of gap renovation decreased as a whole with a single curve; the dead vegetation of a gap was thinner than that inside. As the distance getting farther from the center of a gap to inside, the height and coverage of moss, the thickness and coverage of dead vegetation increased.