3.4. Phytotests with meadow vegetation
Based on the data gathered throughout phytotests with mesic and dry
meadow, the results showed a promising opportunity for implementing the
tested soil substitutes from stage III as trials at the coal mine
affected areas such as Janina Mine waste heap in Libiąż (Figures 4 and
5).
FIGURE 4
FIGURE 5
These plants were less sensitive to the harmful effects induced by
salinity which in case of white mustard significantly limited and even
hampered the first sproutings as well as its further growth.
Additionally, both the mesic and dry meadow plants belong to the
dicotyledonous plants which may develop a dynamic green biomass
production, intensifying the rhizosphere activity and finally increasing
carbon dioxide assimilation. The number of species for the mesic meadow
(Figure 5a) varies between 5 (for A1, B1, C2, C3, and D5) through 6 (for
A2, B2, B3, C1 and D2) to finally the highest number of species, i.e. 7
for D1, which indicates biodiversity of development ecosystems. The
vegetation cover, as a proof of ability to growth in new environments
varied significantly, from 40 to 90%.
The number of species for dry meadow (Figure 5b) fluctuated also in a
large range, from 4 (A2, D3) through 5 (A1, B3, C1, C3, D1, D2) to 6
(A3, B2, C2), reaching even 8 for B1 (Figure 6). The coverage was much
more disparate: from 30 to 90%, whereas 30% applied to only a single
case (D2).
PCA (Table 7) was performed for evaluating the influence of the physical
and chemical parameters of the soil substitutes on the meadow vegetation
development. The first ordination axis of the PCA model (axis 1)
accounts for 65.2 % of the total variation of vegetation. This axis has
a positive correlation with content of OM (0.60) and a negative
correlation with the concentration of P (-0.45). The cover of mesic
meadow species (Flo_Mea, %) and dry meadow species (Dry_Mea, %) has
a negative correlation with this axis. The second axis (axis 2) explains
19.5 % of response variables variation and shows a gradient in soil pH
values. This axis has a positive correlation with the cover of mesic
meadow species and a negative correlation with dry meadow species cover.
The graphical illustration of the PCA analysis was presented in Figure
6.
TABLE 7 Parameters of control soils used in germination tests