Study on Interspecific Relationships among Main Species of Stipa breviflora Communities

The relationship between 21 main species of Stipa breviflora communities were studied by using χ2 test for the 2×2 contingency table and Spearman′s rank correlation analysis.The results indicated that:The pairs that present no significant correlation were more than pairs that present significant and extremely significant correlation.In all of the species pairs,each of the positive correlation coefficients and negative correlation coefficients were almost hold the half.The 21 main species of Stipa breviflora communities could be divided into three ecological groups,viz.Artemisia frigida group,Caragana stenophylla group and Stipa breviflora group.Spearman′s rank correlation coefficient test was more sensitive to study relationship between species.