燕山北部山地不同植物群落物种多样性的空间变化

Spatial variation of species diversity of typical plant communities in North Region of Yanshan Mountain

为了解燕山北部山地不同植物群落物种多样性的差异及其随坡位的空间变化,对该区4种典型植物群落的物种多样性进行了分析。结果表明:不同植物群落的草本层物种多样性随坡位变化未表现出一致的规律性,绣线菊灌丛的多样性随坡位的升高而缓慢增加,但变化不大;榛子灌丛的多样性随坡位的升高先下降后上升;天然杨桦林的多样性随坡位的升高逐渐下降,到上坡位置上变化较小;华北落叶松人工林的多样性没有明显的变化趋势。灌木层多样性的空间变化表现出两种趋势,绣线菊灌丛和天然杨桦林的灌木层表现为中间高两端低,榛子灌丛和华北落叶松人工林的灌木层物种多样性随坡位升高而增加。

In order to understand the spatial variation and the differences of species diversity a- mong the typical plant communities in North Region of Yanshan Mountain, the species diver- sity of 4 kinds of plant communities （Spiraea pubescens shrub, Corylus heterophylla shrub, natural poplar and birch forest and Larix principis-rupprechtii plantation） were studied in the paper. The results showed that there was no consistent spatial trend along slope for her- baceous diversity, and the changes of S. pubescens shrub were smaller, but increased slowly with the rise of slope positions; along with the rising of slope positions, the diversity of C. heterophylla shrub firstly increased after falling; the diversity of natural poplar and birch for- est gradually declined with the rise of slope positions, and the changes in downhill position were smaller; the diversity of the L. principis-rupprechtii plantation had no obvious change trend. There were two kinds of change trends of shrub layer among different plant communi- ties, S. pubescens shrub and natural poplar and birch forest presented higher on middle slope, however lower on upper slope and lower slope, C. heterophylla shrub and L. principis-rup- prechtii plantation increased with the rise of slope positions.