图5. 物种多样性与土壤理化因子的冗余分析(RDA)排序图。灰色虚线箭头表示草本层物种多样性指数, 黑色虚线箭头表示乔木层物种多样性指数, 黑色实线箭头表示灌木层物种多样性指数, 灰色实线箭头表示土壤理化因子。H-S, 草本层丰富度指数; H-H', 草本层多样性指数; H-D, 草本层优势度指数; H-E, 草本层均匀度指数; S-S, 灌木层丰富度指数; S-H', 灌木层多样性指数; S-D, 灌木层优势度指数; S-E, 灌木层均匀度指数; T-S, 乔木层丰富度指数; T-H', 乔木层多样性指数; T-D, 乔木层优势度指数; T-E, 乔木层均匀度指数。AP, 有效磷含量; OM, 有机质含量; SD, 土壤密度; SP, 土壤孔隙度; SWC, 土壤含水量; TN, 全氮含量; TP, 全磷含量。

Fig. 5. Redundancy analysis (RDA) ordination map of species diversity and soil physicochemical factors. The gray dotted line arrow represents the species diversity index of the herb layer, the black dotted line arrow represents the species diversity index of the tree layer, the black solid line arrow represents the species diversity index of the shrub layer, and the gray solid line arrow represents the soil physical and chemical factors. H-S, species richness index of herb layer; H-H', Shannon-Wiener diversity index of herb layer; H-D, Simpson dominance index of herb layer; H-E, Pielou evenness index of herb layer; S-S, species richness index of shrub layer; S-H', Shannon-Wiener diversity index of shrub layer; S-D, Simpson dominance index of shrub layer; S-E, Pielou evenness index of shrub layer; T-S, species richness index of tree layer; T-H', Shannon-Wiener diversity index of tree layer; T-D, Simpson dominance index of tree layer; T-E, Pielou evenness index of tree layer. AP, available phosphorus content; OM, organic matter content; SD, soil density; SP, soil porosity; SWC, soil water content content; TN, total nitrogen content; TP, total phosphorus content.