Figure 4. Leachate pH as affected by soil treatment, plant spe-
cies, and time.
cant. Therefore, results of these analyses will be
Palmerton soil. The alkalinity of the DCR treat-
presented by comparisons of the main factors.
ments neutralized this acidity greatly reducing
Plant shoot, crown, root, and total biomass/
the mobility of Zn.
tube were never statistically different among soil
The plant root and shoot properties were ana-
treatments or between plant species (Fig. 6). De-
lyzed using a two factorial experimental design
spite this lack of statistical significance, there
with soil treatment (clean, Palmerton, DCR,
were clear patterns in both the soil treatments
DCR-compacted) and plant species (perennial
and plant species. The Palmerton treatment (con-
ryegrass and tall fescue) as the main factors. In
taminated) always produced the lowest biomass
these analyses, the soil treatment-plant species
with respect to the other three soil treatments.
interaction term was never statistically signifi-
Figure 5. Leachate Zn concentration as affected by soil
treatment, plant species, and time.
15