Principal coordinate analysis (PCoA) plot illustrating ecological relatedness of RZ and BK soil microbial communities with 22.4% variance explained.

<p>Principal coordinate analysis (PCoA) plot illustrating ecological relatedness of RZ and BK soil microbial communities with 22.4% variance explained.</p

Alder rhizosphere and bulk soil pH after six months of growth in mine residues.

<p>Letters above columns denote significant differences between means (p<0.05), as determined by Tukey’s HSD test.</p

Alder rhizosphere and bulk soil family-level bacterial community profiles after six (6) months of growth, relative to unplanted controls.

<p>(Ac = <i>A</i>. <i>crispa</i>, Ag = <i>A</i>. <i>glutinosa</i>, NT = no treatment, WC = woodchips). Asterisks (*) denote orders designated incertae sedis.</p

Alder growth parameters after six months of growth in mine residues.

<p><b>(A) Biomass expressed as the seedling volume index (SVI); (B) Root length; (C) Root (dry) weight and (D) nodule (dry) weight.</b> Different letters denote significant differences of the mean as determined by Tukey’s HSD test.</p

Alder rhizosphere and bulk soil metal concentrations after six (6) months of growth.

<p>Alder rhizosphere and bulk soil metal concentrations after six (6) months of growth.</p

Alder rhizosphere (RZ) and bulk (BK) soil fungal (ITS) community profiles after six (6) months of growth in mine residues relative to initial (t = 0) controls.

<p>(Ac = <i>A</i>. <i>crispa</i>, Ag = <i>A</i>. <i>glutinosa</i>, NT = no treatment, WC = woodchips).</p

THB population enumeration for alder rhizosphere, alder bulk and control soils initially, i.e. at t = 0 (healthy greenhouse alders) and at t = f (6 months of growth in mine residues) with and without the addition of woodchips as a soil amendment.

<p>THB population enumeration for alder rhizosphere, alder bulk and control soils initially, i.e. at t = 0 (healthy greenhouse alders) and at t = f (6 months of growth in mine residues) with and without the addition of woodchips as a soil amendment.</p

Alder rhizosphere and bulk soil class-level bacterial community profiles after six (6) months of growth, relative to unplanted controls.

<p>(Ac = <i>A</i>. <i>crispa</i>, Ag = <i>A</i>. <i>glutinosa</i>, NT = no treatment, WC = woodchips). Asterisks (*) denote orders designated incertae sedis.</p