秦岭太白红杉群落种间关系的数量分析

Numerical analysis of interspecific relationships in communities of Larix chinensis in Qinling Mountain

应用2×2列联表的Fisher精确检验,研究了太白红杉群落中44种植物 共946个种对 的种间关系.结果有33个种对正关联,12个种对负关联 P<0.05或P<0.01 .另外,用Pearson积矩相关系数和Spearman秩相关系数检验刻划了种对间的数量变化关系.Pearson相关系数显示有31个种对呈显著正协变,5个种对呈显著负协变;Spearman秩相关系数显示有30个种对呈显著正协变,5个种对呈显著负协变,并分别计算出了其相关系数.研究结果表明,太白红杉群落种间关系较为简单,但草本层物种间连接相对较为复杂,灌木层次之.乔木层中,太白红杉和巴山冷杉呈显著的负协变效应.

Fortyfour plant species in communities of Larix chinensis in Qinling Mountain and their interspecific relationship are studied by using Fishers exact test for a 2×2 contingency table.The positive association coefficients of 33 speciespairs for the exact test are either significant or highly significant and negative association coefficients of 12 other speciespairs are significant or highly significant.In addition,Pearsons correlation coefficient and Spearmans rank correlation coefficient are applied to test for correlation between species.The correlation coefficients are calculated.Pearsons correlation coefficient shows that 31 species pairs are very significant positive covariant and 5 species pairs are very significant negative covariant.Spearmans rank correlation coefficient shows that 30 species pairs are very significant positive covariant and 5 species pairs are very significant negative covariant.The results show that the interspecific relationships of communities of Larix chinensis are simpler,but more abundant in herb layer and less in shrub layer.In arbor layer,Larix chinensis and Abies fargesii obviously show their significant negative covariation.