秦岭华北落叶松林乔木种群结构与更新

华北落叶松(Larix principis-rupprechtii)在秦岭属于外来物种。以种群径级结构代替年龄结构,采用静态生命表、生存曲线分析方法,探讨了秦岭华北落叶松种群以及群落中其他乔木的年龄结构和自我更新能力,同时与本地树种华山松林的乔木种群特征进行了比较。结果表明:华北落叶松种群密度较高,幼苗数量少且死亡率较高,种群内其他乔木树种仅有极少量幼苗,乔木的自我更新能力较差。由生命表从动态的角度分析,华北落叶松是一个衰退型种群,华山松则为稳定发展的种群。建议对华北落叶松采取适当间伐,人工促进更新。

A survey on regeneration of trees in Larix principis- rupprechtii forest

Larix principis-rupprechtii is an alien species in the Qinling Mountains.Using the methods of trunk size structure in the place of age structure,together with life table and survival analysis,we investigated the structure and dynamics of L.principis-rupprechtii population and the natural regeneration abilities of other trees in the community,and compared the population characteristics with Pinus armandii forest,a native species of Qinling Mountains.The results showed that the density of L.principis-rupprechtii population was high,with a small number of seedlings and a high mortality rate of seedlings.Other trees in the community had a very small number of seedlings,so their self-regeneration capacity was poor.Analysis by the static life table from a dynamic point of view indicated that L. principis-rupprechtii population was decreased,whereas the P.armandii population maintained steadily.A suggestion is put forward that L.principis-rupprechtii population should be thinned,in order to promote its regeneration.