基于数量分类与排序的雾灵山亚高山草甸群落生态关系分析

The Analysis of Communities' Ecological Correlations in the Subalpine Meadow of Wuling Mountain,Based on Quantitation Classification and Ordination

应用Bray-Curtis相似性聚类分析和非度量MDS排序等数量分析方法,以60个雾灵山的亚高山草甸样方为研究对象,对雾灵山亚高山草甸生态关系进行了研究.结果显示:(1)60个该草甸样方被划分为8个群落类型.金露梅+鹅观草群落(Comm.Potentilla fruticosa+Roegneria kamoji)、地榆+鹅观草群落(Comm.Sanguisorba officinalis+Roegneria kamoji)和鹅观草+拳蓼群落(Comm.Roegneria kamoji+Polygonum bistorta)作为该研究区优势群落类型占总调查样方数的50%.(2)以拳蓼、金露梅为主要优势种或伴生种的群落主要分布在阳坡及半阳坡,而以蒿草为主要优势种的群落大部分分布在阴坡.(3)MDS排序轴第一轴与第二轴分别与坡向、海拔高度梯度变化呈现显著相关关系(R值分别为-0.619和0.399).(4)物种多样性与MDS第一轴呈现显著的正相关.研究表明,分类结果很好地反映了植物群落类型及优势种的分布与环境因子之间的关系,并且在MDS二维排序图上得到了较好的验证.MDS排序轴第一轴与第二轴分别与坡向、海拔高度梯度变化呈现显著相关关系,表明坡向和海拔高度引起的水热条件变化是影响植物群落变化的主要环境因子,此外,群落物种多样性变异同样在该研究区群落类型分化中起重要作用.

Based on cluster analysis and multidimensional scaling,this paper used 60 sampling plots from the subalpine meadow of Wuling Mountain to study the ecological correlation of the subalpine meadow in it.The results showed that：（1） Through cluster analysis,the 60 sampling plots of the subalpine meadow was classified into 8 types of communities.As the dominant communities,Comm.Potentilla fruticosa ＋ Roegneria kamoji,Comm.Sanguisorba officinalis ＋ Roegneria kamoji and Comm.Roegneria kamoji ＋ Polygonum bistorta constituted 50% of the total sampling plots.（2） The communities which dominant species or companion species concluded Polygonum bistorta and Potentilla fruticosa were mainly distributed in slope with sufficient sunshine.However,the communities which dominant species included Kobresia bellardii were mainly distributed in shady slope.（3） Axes1 of MDS ordination had a significantly correlation with the slope aspects （R =-0.619）,while axes2 had a significantly correlation with the altitude above sea level （R =0.399）.（4） The species diversity had a significantly correlation with the first axis of MDS ordination.In conclusion,the results of the classification and ordination better reflected the relationship between the distribution of different plant communities or dominant species and the environmental gradients that was verified in the two-dimension ordination diagram by MDS.MDS ordination gave the ecological significance of ordination axes.Axes1 had a significantly correlation with the slope aspects （R =-0.619）,while axes2 had a significantly correlation with the altitude above sea level （R =0.399）.These means that the variations of water and thermal conditions,caused by slope aspects and altitude above sea level,are the major ecological factors to affect the changes of plant communities.Moreover,the varying species diversity also played a significant role in the changes of plant communities.