长白山区苔草泥炭沼泽植物物种多样性

Plant species diversity of Carex peat mire in Changbai Mountains,China

本研究以长白山区典型苔草沼泽为对象,分析了密丛型苔草(瘤囊苔草、乌拉草)沼泽和疏丛型苔草(毛苔草)沼泽的植物物种多样性。结果表明:3种苔草沼泽植物群落共有83个物种,隶属于36科59属。其中,乌拉草沼泽有71个物种,瘤囊苔草沼泽有61个物种,毛苔草沼泽有26个物种。密丛型苔草沼泽植物物种数和物种丰富度明显高于疏丛型苔草沼泽,且密丛型苔草沼泽草丘位置的物种数和物种丰富度均显著高于丘间位置;草丘的物种丰富度与草丘的高度、基面积和表面积均呈显著正相关,说明草丘对苔草沼泽的物种多样性维持功能具有重要作用。典范对应分析表明,草丘和丘间的水分、养分(有机碳、总氮、总磷、碳氮比)及枯落物厚度的差异是影响物种组成的主要环境因素。在密丛型苔草沼泽中,草丘微地貌主要通过增加表面积和生境异质性来促进沼泽植物物种多样性维持功能。鉴于其较高的物种多样性维持功能,密丛型苔草可以作为退化泥炭沼泽植被恢复的优选物种。

We investigated the plant species richness both in cespitose Carex mires(C.schmidtii,C.meyeriana)and non-cespitose Carex mire(C.lasiocarpa)in Changbai Mountain.A total of 83 species(36 families,59 genuses)was recorded in three sites.Among which,71 species occurred in the C.meyeriana site,61 species in the C.schmidtii site,and 26 species in the C.lasiocarpa site.The total species number and species richness in the two cespitose Carex mires were much higher than that in the non-cespitose Carex mire,while those on tussocks were much higher than between tussocks in the two cespitose Carex mires.Plant species richness on tussocks was positively related to the height,basal circumference and surface area of the tussocks,suggesting that tussocks were important for plant species diversity in Carex mires.Results of the canonical correspondence analysis indicated that the differences in soil water content,nutrient(soil organic carbon,total N,total P and C/N),and litter layer depth were the main factors influencing the differences of plant community composition on tussocks and between-tussocks.In the cespitose Carex mires,the hummock-hollow microtopography could foster high diversity by increasing surface area and creating multiple micro-habitats.Given its function in maintaining high species diversity,cespitose Carex could be a preferred species for vegetation restoration in degraded peat mires.