关键词: χ²检验, Ochiai关联度指数, 昆嵛山 , Spearman秩相关指数, Pearson相关指数

Abstract: The inter-specific relations of shrub and herbage plant communities under a typical forest on Kunyu Mountain were studied by the χ²-test, the Ochiai association index, Pearson's correlation coefficient and Spearman's rank correlation coefficient. First, the results indicate that the pairs having negative correlation are much larger than the positive correlation of all the species pairs. The proportion of speciespairs was small which has a significant or highly significantcorrelation. The shrub and herbage communities on Kunyu Mountain are in the phase of succession. Second, Pearson's correlation coefficient test has big warp in the study. Compared with the χ²-test, the Ochiai association test and Pearson's correlation coefficient test, Spearman's rank correlation coefficient test is more sensitive. Third, the number of speciespairs having highly significant correlation are of the following order: between shrub layer and herbage layer > shrub layer > herbage layer. The shrub layer provided favorable living space for the herbage layer. Finally, the interspecific relations of shrub and herbage layers are different in different forest types. The succession degree in shaw is the deepest one.

Key words: Kunyu Mountain , Spearman's rank correlation coefficient, Pearson's correlation coefficient, Ochiai association index, χ²-test, interspecific relations