林火干扰对长苞铁杉更新的影响

The Efffects Forest Fine Disturhance Tsuga longibracteata Regeneration

通过模拟实验和样地调查研究了林火干扰对长苞铁杉更新的影响,结果表明:长苞铁杉可以在森林火灾迹地中完成其生活史。长苞铁杉在模拟林火干扰样地的幼苗发生率为13%,在人工刈割杂草后样地为10.5%,而在对照组样地为0,杂草的遮荫作用对长苞铁杉幼苗的发生不利。经过一个完整生长季的生长,模拟林火干扰样地内幼苗存活率为68.1%,而人工刈割杂草处理样地内幼苗存活率为0,杂草的竞争提高了长苞铁杉幼苗死亡率。森林火灾迹地中,长苞铁杉更新植株的密度随着距离母树主干距离的加大有下降的趋势。火灾更新迹地中长苞铁杉植株平均高度的分布格局和长苞铁杉植株平均基径的分布格局符合二项式分布。

The effects of forest fire disturbance on Tsuga longibracteata regeneration were studied in this paper by means of field observation,community investigation.Results showed that： The seeds of Tsuga longibracteata could finish its life history at forest fire vestige ground.The seedling emergence rate in forest fire disturbed plots was 13%,that in artificial mowing treated plots was 10.5% and the CK was 0.The shade of weed did harm to seedling emergence of Tsuga longibracteata.After one growing season,the seedling survival rate in simulant forest fire disturbed plots was 68.1%,and that in artificial mowing treated plots was 0.The competition of weed increased seedling mortality.In actual forest fire vestige ground,the density of saplings and seedlings of Tsuga longibracteata showed a decreasing trend along with the distance from the mother tree trunk increasing.The patterns of average height and field diameter of seedlings and saplings at forest fire vestige ground both fited quadratic distributions,with high coefficients of determination.The simulant experiment and investigation of forest fire vestige ground showed Tsuga longibracteata could finish its life history in forest fire vestige ground.