太白红杉林窗更新与环境因子的关系研究

为研究太白红杉的天然更新状况，采用典型样地调查法对太白红杉林的林窗特征及更新数量进行调查，并通过灰色关联分析法对影响太白红杉林天然更新的环境因子进行分析。结果表明:1）在太白红杉林中，实际林窗（CG）和扩展林窗（EG）大小均以100 m²左右的中小面积为主，而且林窗的形成方式主要受风雪影响导致折干；2）林窗下天然更新影响因子关联度排序为林窗面积＞林窗开敞度＞坡位＞坡向＞坡度＞海拔＞枯落物厚度，表明林窗面积和开敞度对林窗天然更新影响最显著；3）幼苗主要集中在中小林窗中，而且在开敞度为0.6~0.8更新最好。因此，建议通过改善林下更新环境，提高太白红杉种子发芽率、幼苗存活率以及成苗率。在具体经营过程中，可以开敞度为指标进行适度经营，人为创造一定的林窗，以加快太白红杉林的天然更新，维持其群落的稳定性。

Relationship between the Regeneration of Larix chinensis and Environmental Factors in Forest Gaps

The natural regeneration of Larix chinensis was studied by surveying the characteristics of forest gaps and the regeneration quantity by using the typical sample survey.The main environmental factors of regeneration were analyzed by using the grey correlation analysis method.The results were reported as follow:1) in the L.chinensis forest,the areas of canopy gap（CG）and extended gap（EG）appeared to have a small-medium sized area of 100 m² dominated distribution,and the formation of forest gaps was mainly affected by wind and snow,resulting in stem breakage.2)The order of correlation degree of influencing factors of natural regeneration under forest gaps was forest gap>opening degree>position>slope aspect>gradient>altitude>litter depth,indicating that the forest gap area and opening degree had the biggest influence on the natural regeneration.3) Seedlings were mainly distributed in the medium and small forest gaps.Besides,the regeneration was the best with the opening degrees between 0.6 and 0.8.It was suggested that measures should be taken to increase the seed germination rate,seedling survival rate and seedling rate by improving the understory environment.In the process of forest management,opening degree could be considered as the index and to artificially create certain forest gaps to accelerate the natural regeneration of the L.chinensis forest and maintain the stability of its community.