林分密度对蒙古栎林下草本植物多样性的影响研究

以内蒙古赤峰市阿鲁科尔沁旗沙日温都栎林自然保护区蒙古栎林为主要研究对象，研究不同林分密度对林下草本植物多样性的影响。结果表明，研究区内共有13科、14属、16种草本植物；Simpson指数、Shannon-Wiener指数、Pielou均匀度指数和物种丰富度指数均随着林分密度的增加呈先增大后减小的趋势，当林分密度为750株/hm²时，林下草本植物多样性指数达到最大值；林分密度与Shannon-Wiener多样性指数、Pielou均匀度指数、Simpson多样性指数、物种丰富度指数、树高、胸径均呈极显著负相关，与郁闭度呈极显著正相关，与枝下高不相关。综上所述，最合理的蒙古栎林密度为750株/hm²，该密度下最有利于蒙古栎林及林下草本植物生长发育。

Effects of Stand Density on Diversity of Understory Herbs in Quercus mongolica Forest

The effects of different stand densities on the diversity of understory herbs were studied based on the case of Quercus mongolica forest in Shariwendu Nature Reserve in Ar Horqin Banner, Chifeng City, Inner Mongolia. The results showed that there were 16 species, 14 genera and 13 families of herbs in the study area; the Simpson index, Shannon-Wiener index, Pielou evenness index and species richness of plant diversity first increased and then decreased with the increase of stand density. When the stand density was 750 plants/hm², the diversity index of understory herbs reached the maximum. Stand density was negatively correlated with Shannon-Wiener index, Pielou evenness index, Simpson diversity index, species richness, tree height and DBH, positively correlated with canopy density, and not correlated with branch height. In conclusion, the most reasonable density of Quercus mongolica forest was 750 plants/hm², which was most conducive to the growth and development and understory herbs.