黄龙山林区油松林封育过程中植物物种多样性特征

对黄龙山林区不同封育年限油松林内的高等植物多样性特征进行了初步分析,结果表明:封育45a以前的油松林,群落内部各层物种丰富度随封育年限增加呈递增趋势,45a后群落内部各层物种丰富度随封育年限增加先增后减;不同封育年限的油松林,物种多样性指数表现出灌木层>乔木层>草本层的趋势,各层次的高等植物物种均匀度指数无相同的变化趋势,灌木层与草本层间各项多样性指数,乔木层与灌木层间,乔木层与草本层间的J和E存在显著差异;在乔木层物种多样性特征上,封育30a和封育75a的油松林差异显著;油松林在封育45a后,具有较高的草本植物物种多样性,但林内幼树密度大,形、质差,应进行卫生伐。

Traits of plant diversity in a hillclosing and afforestation sequence of Pinus tabulaeformis stands in Huanglong Mountains

Traits of plant diversity in a hillclosed and afforested sequence of Pinus tabulaeformis stands in Huanglong Mountains were preliminarily analyzed.The findings show as following.With hillclosing and afforestation ages incensement,species richness in three layers occurs both incensement and decrease trends before and after hillclosed and afforested 45 years in Pinus tabulaeformis stands,respectively.Species diversity indexes show such a trend shrub layers>tree layers>herb layers and their evenness indexes have variable trends in different hillclosed and afforested ages in Pinus tabulaeformis stands.Differences of all diversity indexes between tree layers and herb layers,Pielou evenness indexes and Alatalo evenness indexes between tree layers and shrub layers,tree layers and herb layers were significant.Differences of tree layer species diversity traits were significant between 30 and 75 years hillclosed and afforested Pinus tabulaeformis stands.After hillclosed and afforested 45 years,herb species diversity and density of young Pinus tabulaeformis is high in stands.But shapes and quality of young Pinus tabulaeformis is abnormal.Cut to adjust environment in stands is needed.