辽东山地老秃顶子古冰缘地貌植物种群生态位特征

基于48块样地的群落调查数据,以样地代表多种资源的综合状态,以物种重要值作为生态位计测的状态指标,采用Levins指数与Schoener指数,对辽东山地老秃顶子古冰缘地貌植物群落乔木层、灌木层及草本层植物的生态位特征进行了系统研究。结果表明：① 乔木层内臭冷杉（Abies nephrolepis）生态位宽度最大,为泛化乔木种;臭冷杉与长白鱼鳞云杉（Picea jezoensis var. komarovii）的生态位重叠值高达0.616,共优生存于暗针叶林中。② 灌木层内生态位宽度较大的狗枣猕猴桃（Actinidia kolomikta）、单花忍冬（Lonicera subhispida）、大翅卫矛（Euonymus macropterus）和关东丁香（Syringa velutina）为落叶阔叶林和针阔混交林下的泛化种;狗枣猕猴桃与单花忍冬的生态位重叠值高达0.610。③ 草本层内生态位宽度较大的东北羊角芹（Aegopodium alpestre）、荨麻叶龙头草（Meehania urticifolia）、酢浆草（Oxalis corniculata）为研究区泛化草本植物;东北羊角芹与荨麻叶龙头草的生态位重叠值高达0.702。

Niche characteristics of plant populations in the paleo-periglacial areas of Mt. Laotudingzi,eastern Liaoning mountainous region

Based on the community survey in 48 sampling areas, we use the samples to signify the comprehensive state, and the species importance values as the state index of niche instrumentation. We employ Levins and Schoener indices to study niche breadth and niche overlaps of three layers of arbor, shrub and herb in paleo-periglacial areas of Mt. Laotudingzi, eastern Liaoning mountainous region. The results show: (1) In the arbor layer, the niche breadth of Abies nephrolepis, Tilia amurensis, Acer barbinerve, Betula ermanii and Picea jezoensis var. komarovii are much larger than that of others, among them, the Abies nephrolepis is the generalized arbor seed, and Tilia amurensis is the constructive species of forest community below 800 m, while the Acer barbinerve, Betula ermanii and Picea jezoensis var. komarovii are the constructive species of forest community above 800 m. The value of niche overlap between Abies nephrolepis and Picea jezoensis var. komarovii is as high as 0.616, showing that these species had similar biological characteristics, and adapted to each other in the long-term process of communities succession, which formed an optimal survival state in the dark coniferous forest. (2) In the shrub layer, the niche breadth of Actinidia kolomikta, Lonicera subhispida, Euonymus macropterus and Syringa velutina are larger than that of others, which has already evolved into the generalization plants of the deciduous broad-leaved forest and mixed needle- and broad-leaved deciduous forest. The values of niche overlaps between Actinidia kolomikta and Lonicera subhispida, Syringa velutina, Euonymus macropterus, Euonymus pauciflorus range from 0.515 to 0.610, which have high similarity of demand for environmental resources between all these species. (3) In the herb layer, the niche breadth of Aegopodium alpestre, Meehania urticifolia, Oxalis corniculata, Circaea alpine are larger than that of others, which has already evolved into the generalization plants. The value of niche overlaps between Aegopodium alpestre and Meehania urticifolia is as high as 0.702, and the values between Oxalis corniculata and Circaea alpine, Spuriopimpinella brachycarpa and Aegopodium alpestre, Spuriopimpinella brachycarpa and Phlomis maximowiczii are from 0.556 to 0.580. (4) The niche overlaps between major populations were quite common, but the overlap degree of species was relatively less, part of the species niche even separated completely, which shows that it is not so fierce for the major plant populations to compete for the same environmental resources.