Abstract:

Based on the 2×2 contingency tables of species presence/absence data collected from a 42 hm² permanent plot in the coniferous and board-leaved mixed forest in Jiaohe, the VR analysis, χ²-test, Pearson correlation coefficient test and Spearman rank correlation coefficient test were used in quantitative analysis of the interspecific correlations of 18 dominant species. The results indicated that there was a significantly positive correlation of overall association in the broad-leaved mixed forest community, but most species were insignificant positive correlation. The result of χ²-test showed that there was a positive association for 85 species-pairs and a negative association for 65 species-pairs. The Spearman rank correlation coefficient test produced more positive correlation species-pairs than the Pearson correlation coefficient test. The positive associations were presented among overall tree species of the community, which suggested the adaptability of species to similar habitats and the niche overlapped. The interspecific correlations were probably associated with ecological habitats. According to the semi-matrix figure correlation coefficients and the ecological characteristics, the 18 dominant species divided into three ecological species groups.

Key words: interspecific correlation, niche overlap, correlation coefficient test, ecological species groups