基于林缘效应对兴安落叶松天然更新及分布格局的研究
Natural Regeneration and Distribution Pattern of Larix gmelini Based on Forest Edge Effect

基于大兴安岭3块林缘样地，研究兴安落叶松林缘更新的规律，明确其特殊的更新环境和更新效果，为兴安落叶松林缘区域的林木更新以及兴安落叶松更新扩张方向的预测提供一定的理论基础。用7种聚集度指标分析更新木空间分布类型及聚集强度，对比分析3块不同类型林缘样地的更新数量情况。结果表明，从林缘到林内兴安落叶松更新木的空间分布格局，除个别受干扰的区域均匀分布，其他均为聚集分布；林缘区域的更新木聚集度比林内更新木聚集度大；兴安落叶松林缘区域的更新数量比林内多，林缘效应影响兴安落叶松更新的范围在距离林缘20 m左右；光照条件好、光照时间较长的南向林缘更新情况较好；森林与不同的群落形成不同的林缘类型，林外土壤水分等条件较好的塔头草地林缘更新情况更好。林缘效应能够促进兴安落叶松天然更新，不同的林缘类型和林缘方向更新效果有差异。
Based on three different forest edge plots in the Daxing？an Mountains of Inner Mongolia,the law of forest edge regeneration of Larix gmelinii was investigated.Its special regeneration environment and renewal effect were clarified.At the same time,the tree renewal at the edge of L.gmelinii forest and the prediction of the expansion direction of L.gmelinii forest were identified to provide theoretical basis.Seven types of aggregation indexes were used to analyze the updated tree spatial distribution types and aggregation strengths,and to compare and analyze the updated number of three sample plots.The results showed that the spatial distribution pattern of the updated tree from the margin of forest to the forest of L.gmelinii was uniform except for the individual disturbed areas,and the others all presented clustered distributions.The degree of renewal tree in the forest edge region was greater than that of the renewal tree within the forest.The results showed that the forest margin of L.gmelinii was better than that of the forest.The effect of forest margin on the regeneration of L.gmelinii forest was about 20 m away from the edge of the forest margin.The forest edge at south-facing direction that had good light conditions and long sunshine duration presented better regeneration trend.Forest and different plant communities formed different types of forest margins,in which forest edge together with “tower-head shape” grass demonstrated better soil moisture,and regenerated much better.The forest margin effect could promote the natural regeneration of L.gmelinii,and there were differences in the regeneration effects of different forest edge types and forest margin directions