Insight into the Adaptability of Dominant Plant Indigofera amblyantha Craib for Ecological Restoration of Rock Slopes in Stone Coal Mine

Figure 4

The RDA ranking diagram of species importance values and factors in substrate material. (a) nutrient factors and (b) heavy metals in the artificial soil matrix. Solid arrows represent species information and hollow arrows represent environmental factors. The testing and stepwise selection method: summarize effects of explained variables and unrestricted permutations.

(a)

(b)