塞罕坝不同发育阶段白杄人工林林下植被多样性研究

Understory Vegetation-Diversity of Picea meyeri Forest Planation at Different Development Stages in Saihanba Machinery Forest Farm

为更好了解塞罕坝机械林场白杄人工林不同发育阶段林下植被生物多样性现状,对不同发育阶段的白杄人工林林下植被的丰富度、重要值和多样性进行研究。结果表明:不同发育阶段白杄人工林的灌木层的丰富度和多样性差异不大,其占优势地位的物种均为华北落叶松;在幼龄林阶段,草本层优势物种为生长在立地条件较差的干旱山坡的细叶苔草、扁蓿豆等,中龄林和近熟林阶段,这些植物的优势地位明显下降,优势植物变成了一些耐荫植物;草本层丰富度、多样性指数和均匀度指数表现为中龄林好于幼龄林和近熟林。

In order to know vegetation biodiversity of understory community of Picea rneyeri planations at different development stages in Saihanba Machinery Forest Farm, species richness, important value, species diversity index of Picea meyeri planations at different development stages were studied. Results shows that： there is no signifiance differences in species richness and species diversity among different development stages of shrub layer, and Larix principis rupprechtii is dominant; in the young forest stage, the dominant species of the herbaceous layer are Carecc rigescens and Melilotoides ruthenica, which grow on the arid hillside. The dominant position of these plants in the half mature forest and near mature forest is significantly reduced, and the dominant plants become shade tol erant plants; herb layer richness, diversity index and evenness index shows that middle aged forests are optimal than younger and near mature forests.