不同强度间伐对长白山天然林林下植物多样性的影响

对吉林森工集团松江河林业局辖区内的阔叶红松林、杂木林和杨桦林采取30%～40%（T1）、20%（T2）株数强度的均匀间伐处理,以不间伐处理为对照（CK）,对间伐2 a后林下植物木本、草本植物进行调查,采用Simpson、Shannon-Wiener多样性指数和Pielou均匀度指数进行植物多样性分析,探讨不同强度间伐对3个林型林下植物多样性的影响。研究结果表明：T1间伐后3个林型的物种丰富度均有增加（杂木林木本植物例外）,T2间伐后杨桦林木本植物丰富度降低,草本植物丰富度增加。两种间伐处理均增加阔叶红松林木本植物多样性,T1处理尤为明显。T1处理增加杂木林和杨桦林木本植物多样性,而T2间伐处理有较弱的降低作用。两种间伐处理均降低阔叶红松林和杂木林草本植物多样性,与强度无明显关系。随着间伐强度的增加杨桦林草本植物多样性增大。在长白山天然林中,较大间伐强度T1（30%～40%）能够有效提高植物多样性。

Effect of Thinning Intensity on Species Diversity of Different Forest Stands in Changbai Mountain

The woody and herbaceous plants under three different forest stands of broad-leaved tree and Korean pine forests,mixed forests and poplar-brich forests thinned 2-year-ago with the intensity of 30%—40%（T1）,20%（T2）and CK were surveyed in the area of Songjianghe Forestry Bureau of Jilin Forestry Industry Group Co.,Ltd.And the effects of different thinning intensities on species diversity of the three forest stands were analyzed respectively by Simpson diversity index,Shannon-Wiener diversity index and Pielou evenness index.Results show that the T1 treatment increases the species abundance in three different forest stands except the woody plants in Mixed forests.T2 treatment decreases the species abundance of the woody plants but increases the species abundance of herbaceous plants in Poplar-brich forests.T1 and T2 treatment increases the species diversity in Broad-leaved tree and Korean pine forests,and the effect of T1 is especially obvious.T1 treatment increases the species diversity of the woody plants,but T2 treatment slightly decreases in Mixed forests and Poplar-brich forests.Both T1 and T2 treatment decreases the species diversity of herbaceous plants in Broad-leaved tree and Korean pine forests and Mixed forests,with no evident relation between the species diversity and thinning intensity.With the increasing of thinning intensity,the species diversity of herbaceous plants increases in Poplar-brich forests.In the natural forest of Changbai Mountain area,the plant diversity can be effectively improved under higher thinning intensity T1（30%~40%）.