老秃顶子石河冰缘地貌森林群落物种多样性及其影响因素

Forest Community Species Diversity and the Influencing Factors in the Rock Stream Periglacial Landforms of Mt.Laotudingzi

基于对24个样地的调查数据,采用物种丰富度指数、Shannon-Wiener指数以及Jaccard相似性指数,对辽东山地老秃顶子石河冰缘地貌森林群落物种多样性及其影响因子进行了研究。结果显示：（1）石河冰缘地貌森林群落中落叶阔叶林、针阔混交林和暗针叶林的物种丰富度指数平均值分别为41±10、34±5和31±7。森林群落物种丰富度变异系数均为中等变异性。（2）石河冰缘地貌森林群落中落叶阔叶林、针阔混交林和暗针叶林的Shannon-Wiener指数平均值分别为1.67±0.32、1.50±0.18和1.29±0.25。（3）石河冰缘地貌森林群落间Jaccard相似性指数为0.037~0.530,且集中在极不相似和中等不相似区间。（4）相关性分析结果显示,石河冰缘地貌海拔高度与森林群落乔木层物种丰富度指数、Shannon-Wiener指数呈极显著负相关（P〈0.01）,与灌木层物种丰富度指数呈显著负相关（P〈0.05）;土壤电导率和含盐量均与森林群落物种多样性指数呈显著正相关（P〈0.05）;土壤pH值与灌木层物种丰富度指数、Shannon-Wiener指数呈极显著正相关（P〈0.01）;土壤CaO含量分别与乔木层和灌木层的物种丰富度指数、乔木层Shannon-Wiener指数呈显著正相关（P〈0.05）。这表明海拔高度、土壤电导率、盐含量、pH值和CaO含量是影响石河冰缘地貌森林群落物种多样性变化的重要因素。

Based on field survey data from 24 plots,we studied the forest community species diversity using the species richness,Shannon-Wiener and Jaccard similarity indices and the influencing factors in the rock stream periglacial landforms of Mt.Laotudingzi.The results showed that：（1）The average species richness index values for the deciduous broad-leaf,mixed broadleafconifer,and dark coniferous forests were 41 ± 10,34 ± 5 and 31 ± 7,respectively.The variation coefficients of the species richness index of the forest community exhibited moderate variability.（2）The average Shannon-Wiener index values for the deciduous broad-leaved,mixedbroadleaf-conifer,and dark coniferous forests were 1.67 ± 0.32,1.50 ± 0.18 and 1.29 ±0.25,respectively.（3）Similarity index values among plant populations of the rock stream periglacial landforms varied between 0.037 and 0.530,and were concentrated in two intervals of0.25-0.5 and 0-0.25.（4）Correlation analysis showed that rock stream periglacial landforms altitude had a significant negative correlation with the species richness and Shannon-Wiener index of the forest community tree layer（P〈 0.01）,and an obvious negative correlation with the species richness of the shrub layer（P 〈0.05）.Both soil electrical conductivity and salt content had obvious positive correlations with species diversity of forest community in the rock stream periglacial landforms（P〈 0.05）.The pH value of the soil had a significant positive correlation with the species richness and Shannon-Wiener index of the shrub layer（P 〈0.01）.The CaO content in the soil had an obvious positive correlation with the Shannon-Wiener index and species richness of the tree and shrub layers（P 〈0.05）.Therefore,changes in plant diversity of the rock stream periglacial landforms were primarily influenced by altitude and the electrical conductivity,salt content,pH value and CaO content of the soil.