太行山中段植物群落草本植物优势种种间联结性分析

植物种间关联研究对揭示植物对生境变化的响应及植被演替机制具有重要意义。运用2×2列联表、2χ检验方法对群落草本植物优势种进行总体相关性和种对间的联结性检验,应用Spearman秩相关系数刻画种对间的数量变化关系,对太行山中段植物群落草本层中重要值较高的32个优势种群、496个种对间的关联性进行定量研究。结果表明,太行山中段草本植物优势种整体上多呈现正关联,群落处于较稳定的演替阶段。其中2χ检验结果有75个种对呈极显著正关联,74个种对呈显著正关联,只有20个种对为不显著的负关联。Spearman秩相关分析结果有43个种对呈极显著相关,79个种对呈显著相关,只有6对为不显著的负相关。对生境要求相同或相似的种对表现出显著的正关联。χ2检验呈显著、极显著相关的种对数多于秩相关分析。

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.