Interspecific association and correlation of dominant herbs in plant community in the midst of Taihang Mountains

To study the interspecific association of plants is of significance in understanding the responses of plant species to habitat change and the mechanisms of vegetation succession.68 plots in the midst of Taihang Mountain were sampled and 32 dominant species were selected according to the important value to study the interspecific associations and correlations by using χ2 test for 2×2 contingency table and Spearman's rank correlation coefficient.The results showed that the overall associations among dominant species in community were positive,and the relationships among species-pairs were varied with environmental conditions in different types of community,reflecting a certain trend of community succession.The interspecific correlations among 496 species-pairs of the 32 dominant species showed that 75 species-pairs were distinctly significant positive association,74 species-pairs were significant positive association,20 species-pairs were negative association based on χ2 test,however,they were 43,79 and 6 respectively based on Spearman's rank correlation coefficient test.Species with positive association have similar biological characteristics and similar habitats.The calculated value by χ2 test was higher than Spearman rank correlation test.