间伐强度对油松中龄人工林林下植被多样性的影响

Effects of the thinning intensity on the diversity of undergrowth vegetation in Pinus tabulaeformis plantations

从植物多样性角度探讨了不同间伐强度对人工油松中龄林的影响,分析了林下植被的生物多样性。结果表明:在相似地力条件下,随着间伐强度的增加,林下植被科、属、种的数量增加,植物多样性增加,尤其是草本层多样性指数、丰富度指数、均匀度指数均逐渐上升,层次结构更加明显;间伐强度的增加改变了林下植被的生活型谱,阳生、喜暖植物的比例增加,同时有利于林下植被生物量的增加。对相似立地条件下45年生初植密度为3 500株/hm2的油松中龄林选择44%的间伐强度处理,3年后林下植被发育及乔木生长状况较好。

The index species diversity was used to discussing the stand or fall of intermediate cutting intensity. The result showed that, the number of the family, the genus, and the species of undergrowth vegetation species increased with thinning increasing. Species diversity, evenness index and richness index increased as well. There were some changes in the life-form spectrum and of plant community of Pinus tabulaeformis. The results also showed that the density of plant community of half mature P. tabulaeformis needed be further tended and thinned. The density should be controlled below 1 900 - 2 200 tree/hm^2.