间伐对华北落叶松人工林林下植被的短期影响

为了解抚育间伐对华北落叶松纯林林下植被的影响,对河北省木兰林管局600,900,1 200,1 500株/hm2共4种不同密度华北落叶松人工林林下植被进行了调查。结果表明,华北落叶松人工林林下植被物种丰富度,平均高度、平均盖度、平均密度、植物多样性指数随着保留密度的增大而减小,且密度600株/hm2和900株/hm2落叶松林下植被的各项指标都相接近,与其它2种密度林下植被相差较大;较小密度之间的林下植被物种组成相似程度较大,较大密度和较小密度落叶松之间林下植被物种组成差异较大;40 a生左右、平均高为11m、密度为1 500株/hm2的华北落叶松间伐保留密度为900株/hm2较为合理。

Effects of Thinning on the Undergrowth Vegetation of Larix principis-rupprechtii Plantation

Investigation was carried out on the undergrowth vegetation of Larix principis-rupprechtii plantation with the different thinning intensities in order to understand the effects of tending and thinning.Results indicated that species richness,mean height,mean density,species diversity indices decreased gradually with the increase of retention density.The undergrowth vegetation with 600 plants/hm2 and 900 plants/hm2 had the similar indices values but differed considerably with others.Species composition was similar greatly among the lower densities but more different among the lower and higher ones.That Larix principis-rupprechtii plantation,40-year-old and 10 meters'height with 1500 plants/hm2 was retained to the density of 900 plants/hm2,which was more reasonable.