关键词: 角突臂尾轮虫, 食物浓度, 种群增长率, 个体大小　卵大小

Abstract: By using variance ratio (VR) of overall association, χ²-test, Jaccard association index, Pearson coefficient, and Spearman rank coefficient, this paper studied the interspecific association and correlation of 20 main plant species in the subalpine meadow of Zibai Mountain. Among the 20 species, few pairs had significant or very significant interspecific association (correlation). The ratios of positive and negative associations (correlations) by χ²-test, Pearson coefficient, and Spearman rank coefficient were 0.85, 0.61, and 1.02, respectively, suggesting that the plant community was relatively stable. According to Spearman rank correlation coefficient, the 20 species were divided into 4 ecological groups. In each group, the species had the similar ecological demands and the similar ways of utilizing resources; among the groups, there was an obvious transform and succession trend. Positive association (correlation) occurred between the species pairs having similar biological traits and similar ecological adaptability to habitats, whereas negative association (correlation) occurred between the species pairs having different biological features and different ecological adaptability to habitats.

Key words: Brachionus angularis, Food concentration, Population growth rate, Body size, Egg size