鳞籽莎对间伐后林下植物多样性的影响

The Effect of Lepidosperma chinense on Understory Diversity After Thinning

以广州流溪河次生林为研究对象,分析间伐1.5 a后林下植物的组成、相似性、重要值和多样性,研究多年生草本植物鳞籽莎对间伐后林下植被多样性的影响。结果表明:26个小样方共记录林下植物102种,隶属51科,84属。间伐总体上增加了林下植物的物种多样性,其中对灌木层(含乔木幼苗和幼树)的影响较明显。与非鳞籽莎样地相比,鳞籽莎样地的林下植物物种数量较少,并且物种相似性系数较低,间伐对其物种数量的增加值不如非鳞籽莎样地显著;且间伐对非鳞籽莎样地林下植物多样性指数的增强效果较鳞籽莎样地显著。从而表明间伐在短期内能一定程度增加林下植物的多样性,但是间伐对鳞籽莎样地林下植物影响效果较非鳞籽莎样地差,鳞籽莎的大量存在显著削弱了间伐对林下植物的影响效果。

Taking the Liuxi River secondary forest in Guangzhou as the research object,the composition,similarity,important value and diversity of understory vegetation after 1. 5 years of thinning were analyzed. The effects of Lepidosperma chinense on the diversity of understory vegetation after thinning were studied. Result showed that a total of 102 species of understory vegetation were recorded in 26 sample plots,belonging to 51 families and 84 genera. The thinning increases the species diversity of understory vegetation in general. The effect on the shrub layer（ including arbor seedlings and saplings） was obvious. Compared with non-L. chinense sample plots,the number of understory vegetation species in the L. chinense sample plots was small,and the similarity coefficient of the species was lower,and the increase in the number of species by thinning was not as significant as that in the nonL. chinense sample plot. The thinning effect on the diversity index of the understory vegetation species in the nonL. chinense sample plot was significantly greater than that on the L. chinense sample plots. This shows that thinning can increase the diversity of understory vegetation in a short period of time,but the effect of thinning on the understory vegetation in the L. chinense sample plots was worse than that of the non-L. chinense. The presence of a large amount of L. chinense significantly impaired the effect of thinning on understory vegetation.