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采用样方法调查了秦岭山地5种典型次生林——油松林、锐齿栎林、红桦林、云杉林和华山松林幼苗的更新特征.结果表明:不同次生林木本植物幼苗物种分化明显,除锐齿栎林和华山松林外,其余次生林幼苗物种相似性系数均较低;油松林和锐齿栎林木本植物幼苗数量、物种丰富度指数、Simpson优势度指数及均匀度指数均较高,红桦林均最低;云杉林和华山松林幼苗数量及物种多样性指数基本一致.不同次生林幼苗和幼树所占比例存在明显差异,除红桦林幼树数量的比例较大外,其余林分幼苗的比例较大,为云杉林>油松林>锐齿栎林>华山松林.不同林分幼苗萌生比例差异明显,为华山松林>云杉林>红桦林>锐齿栎林>油松林.锐齿栎林和油松林乔木幼苗比例最高,分别占木本幼苗总种数的68%和51.4%,群落处于演替中期,持续更新能力较强;云杉林、华山松林乔木幼苗比例分别为40%和15%,处于演替后期,更新能力较差;而红桦林中幼苗很难发育成幼树,持续更新能力欠缺.
The regeneration characteristics of five typical secondary forests - Pinus tabulaeformis, Quercus aliena, Betula platyphylla, Picea schrenkiana and Pinus armandi were studied by sampling method.The results showed that the seedlings of different secondary species of woody plant were well differentiated except The similarity coefficient of seedlings of the secondary forest was lower than that of the natural forests except for the Quercus aliena and the Pinus armandii forests. The numbers of seedlings, species richness index, Simpson dominance index and evenness index of the woody plants of Pinus tabulaeformis and Sharptooth oak forest were higher, Birch forest were the lowest.The numbers of seedlings and species diversity index of spruce forest and Pinus armandii forest were basically the same.The proportions of seedlings and saplings in different secondary forests were significantly different except for the proportion of young trees in birch forest.The remaining seedlings The proportions of spruce forest> Pinus tabulaeformis forest> sharptooth oak forest> Pinus armandii forest were significantly different among different stands, which were Pinus armandii forest> spruce forest> birch forest> sharptooth oak forest> Pinus tabulaeformis forest The highest proportion of tree seedlings was in Quercus aliena and Pinus tabulaeformis forests, accounting for 68% and 51.4% of the total seedlings respectively. The community was in the mid-succession stage and had strong ability of continuous regeneration. The proportion of tree seedlings in spruce and Pinus armandi forests was 40 % And 15%, respectively, in the late succession, the ability to update less; and birch forest seedlings difficult to develop into saplings, continuous lack of ability to update.