大兴安岭地区不同类型多年冻土区灌丛-薹草沼泽植物群落组成及其物种多样性

为了明确大兴安岭地区不同类型多年冻土区灌丛-薹草沼泽植物群落组成和物种多样性的差异,于2015年8月和2018年8月,采用野外调查和室内分析相结合的方法,利用Margalef丰富度指数、Shannon-Wiener多样性指数、Pielou均匀度指数和Cody指数、Sorenson指数研究调查区域植物群落的α多样性和β多样性特征。研究结果表明,2015年8月和2018年8月分别共记录植物10科15属18种和16科21属24种;大兴安岭不同类型多年冻土区灌丛-薹草沼泽指示物种存在差异,图强湿地(大片连续多年冻土区)灌丛-薹草沼泽植物群落物种组成有向温度相对较高的南瓮河湿地(零星岛状多年冻土区)灌丛-薹草沼泽植物群落物种组成方向发展的趋势;图强湿地、新林湿地(不连续岛状多年冻土区)和南瓮河湿地灌丛-薹草沼泽中植物群落的平均Margalef丰富度指数分别为1.607、1.431和1.754,平均Shannon-Wiener多样性指数分别为1.016、1.333和1.272,平均Pielou均匀度指数分别为0.429、0.590和0.533;图强湿地与新林湿地的灌丛-薹草沼泽植物群落物种之间的更替速率较快,二者灌丛-薹草沼泽中的植物群落较相似。对比不同类型多年冻土区灌丛-薹草沼泽植物群落物种组成与多样性变化发现,灌丛-薹草沼泽中的植物对气候变化有潜在响应,但是,植物应对气候变化也与物种自身性质和立地环境有关,尚需进一步开展长期而深入的研究。

Composition of Plant Communities in Shrub-Carex Swamps and Their Species Diversity in Different Types of Permafrost Zones in Daxinganling Region

Plants in the wetlands in permafrost region are important part of boreal ecosystem. In order to obtain the heterogeneity of composition of plant communities and diversity of shrub-Carex swamps in different permafrost zones in Daxinganling region. The field investigation and laboratory analysis in August 2015 and August 2018 were carried out. Margalef richness index, Shannon-Wiener diversity index, Pielou evenness index, Cody index, and Sorenson index were used to study α diversity and β diversity characteristics of the plant communities in this area. The results showed that 18 species belonged to 10 families and 15 genera were recorded in August 2015, while 24 species were recorded belong to 16 families and 21 genera in the swamps in August 2018. There were different indicator species in the swamps in this region. Using non-metric multidimensional scaling analysis, the species composition of the plant community in the swamps in continuous permafrost zone tended to that in the sporadic island permafrost zone with temperature rising.Mean Margalef’s richness indexes of the plant communities in the swamps in continuous permafrost zone,discontinuous and sporadic island permafrost zones were 1.607, 1.431 and 1.754, Shannon Wiener’s diversity indexes were 1.016, 1.333 and 1.272, and Pielou’s evenness indexes were 0.429, 0.590 and 0.533. The Cody index showed that the species turnover rate was faster between the plant communities in the swamps in Tuqiang wetland in continuous permafrost zone and Xinlin wetland in discontinuous island permafrost zone,while the Sorenson index was the also larger between them.