大兴安岭沟谷冻土湿地植物群落物种多样性梯度变化.doc

大兴安岭沟谷冻土湿地植物群落物种多样性的纬度梯度变化* 孙菊1,2，李秀珍1*，王宪伟1,2，吕久俊1,2，李宗梅1,2 （1中国科学院沈阳应用生态研究所，沈阳110016；1,2中国科学院研究生院，北京100049） 摘 要 本文以大兴安岭沟谷冻土湿地植物群落为研究对象，探讨其物种多样性随纬度梯度变化的规律。结果表明，在大兴安岭沟谷冻土湿地植物群落中，随着纬度的逐渐降低，草本层植物的科、属和物种数目均呈极显著的线性增加(P0.01)灌木层植物的科、属和物种数目均呈极显著的线性减(P0.01)；群落的物种组成随着纬度发生变异，草本层和灌木层的主要优势物种在群落中的重要值排序发生变化。冻土湿地植物群落的α多样性沿纬度梯度的分布格局在不同生活型的物种之间不同随着纬度的逐渐降低，草本层物种多样性增大，灌木层物种多样性减小。冻土湿地植物群落的物种多样性与物种丰富度的变化格局一致，与优势度的变化趋势正好相反。灌木层的物种均匀度随纬度的降低呈极显著线性减小（P0.01），草本层的均匀度在各个纬度梯度上的变化相差不大。对于不同生活型的物种，冻土湿地植物群落?多样性沿纬度梯度具有相似的变化格局，即随纬度梯度的升高，草本层和灌木层的?多样性均先降低后升高再降低。在纬度较高的样地，群落之间草本层物种的组成比较相似。 关键词 大兴安岭；冻土；湿地；物种多样性；纬度梯度 Q145+.2 文献标识码：A Changes of species diversity of plant communities along latitude gradient in valley permafrost wetlands of Daxing’an Mountains. SUN Ju1, 2, LI Xiu-zhen1, Wang Xian-wei 1, 2, Lv Jiu-jun 1, 2, Li Zong-mei 1 (1Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China; 2Graduate University of Chinese Academy of Sciences, Beijing 100049, China) . Abstract: Studying the changes of species diversity in plant communities along latitude gradients is important to discover the correlation between biodiversity and environmental factors. Along the main ridges of Daxing’an Mountains, 12 natural permafrost wetlands in the valleys were investigated from the north to the south. The scientific name, number, height, and cover of each plant were recorded for each sample plot. Latitude, longitude and altitude of each plot were also recorded. The change pattern of species diversity along latitude gradients was analyzed with regressive analysis. Over 150 plant species were recorded and were found to be in 12 permafrost wetlands plant communities. Most plants belong to the Compositae or Gramineae. Family number, genus number and species number increased linearly in the herb layer with the decrease of latitude (P0.01), while they decreased linearly in the shrub layer (P0.01). Species composition of the plant communities changed along latitude, and the predominant