# Metal Mobility in Afforested Sites of an Abandoned Zn-Pb Ore Mining Area
## 4 Discussion
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Profile** & **Depth [m]** & **Dominated Minerals** \\ \hline \multicolumn{3}{c}{Lgota} \\ \hline \multirow{3}{*}{Lgota I} & 0.82–0.97 & dolomite \({}^{1}\), ankerite \({}^{2}\), quartz \({}^{3}\), goethite \({}^{4}\), 14 Å mineral \({}^{13}\) \\ \cline{2-3}  & 1.12–1.30 & dolomite \({}^{1}\), quartz \({}^{3}\), ankerite \({}^{2}\), kaolin group of minerals \({}^{5}\), goethite \({}^{4}\), \\  & 14 Å mineral \({}^{13}\) \\ \hline \multirow{3}{*}{Lgota II} & 0.37–0.47 & dolomite \({}^{1}\), quartz \({}^{3}\), ankerite \({}^{2}\), goethite \({}^{4}\), kaolin group of minerals \({}^{5}\), \\  & 14 Å mineral \({}^{13}\) \\ \hline \multirow{3}{*}{Lgota III} & 0.05–0.10 & quartz \({}^{3}\), dolomite \({}^{1}\), ankerite \({}^{2}\), kaolin group of minerals \({}^{5}\), albite \({}^{9}\), goethite \({}^{4}\) \\ \hline \multirow{3}{*}{Paryz} & 0.27–0.37 & quartz \({}^{3}\), kaolin group of minerals \({}^{5}\), albite \({}^{9}\), microclin \({}^{10}\), dolomite \({}^{1}\), ankerite \({}^{2}\) \\ \hline \multirow{3}{*}{Paryz I} & 0.09–0.15 & minrecodite \({}^{6}\), dolomite \({}^{1}\), hemimorphite \({}^{7}\), cerussite \({}^{11}\), quartz \({}^{3}\), anglesite\({}^{12}\) \\ \cline{2-3}  & 0.60–0.67 & minrecodite \({}^{6}\), dolomite \({}^{1}\), smithsonite \({}^{8}\), hemimorphite \({}^{7}\), 14 Å mineral \({}^{13}\) \\ \hline \multirow{3}{*}{Paryz II} & 0.06–0.18 & dolomite \({}^{1}\), ankerite \({}^{2}\), hemimorphic \({}^{7}\), cerussite \({}^{11}\), kaolin group of minerals \({}^{5}\), \\  & 0.24–0.37 & quartz \({}^{3}\), minrecodite \({}^{6}\), dolomite \({}^{1}\), hemimorphite \({}^{7}\), 14 Å mineral \({}^{13}\), cerussite \({}^{11}\) \\ \hline Paryz III & 0.14–0.20 & minrecodite \({}^{6}\), dolomite \({}^{1}\), quartz \({}^{3}\), hemimorphite \({}^{7}\), cerussite \({}^{11}\), smithsonite \({}^{8}\) \\ \hline \multicolumn{3}{c}{\({}^{1}\)CaMg(CO)\({}_{3}\):2\({}^{\circ}\)Ca(Fe\({}^{+}\)2,Mg\({}^{+}\)Mn\({}^{+}\))(CO)\({}_{2}\):3\({}^{\circ}\)SiO\({}_{2}\):4 Fe\({}^{+}\)O(OH):5 Al\({}_{5}\)Si\({}_{2}\)O(OH)\({}_{4}\):6 CaZn(CO)\({}_{3}\):7 Zn\({}_{5}\)Si\({}_{2}\)O(OH)\({}_{2}\):H\({}_{2}\)O;} \\ \multicolumn{3}{c}{\({}^{8}\)ZnCO\({}_{3}\):9 NaAlSi\({}_{3}\)O\({}_{8}\):10 KAlSi\({}_{3}\)O\({}_{8}\):11 PbCO\({}_{3}\):12 PbSO\({}_{4}\):13 14 Angstrom minerals.} \\ \end{tabular}
\end{table} 
Table 5: Dominant minerals in the Lgota and Paryz profiles. the increase in surficial organic matter content (expressed as LOI) toward maximum values in the outer parts of both heaps. Progressive degradation, mainly of beech leaves (Lgota) and pine needles (Paryz), takes place in the ca. 10 cm of the surface of each profile and is also a source of humic acid for the lower soil horizons. The phenomenon of the acidification of soils is well known, particularly in coniferous forests [31; 32; 33; 34; 35]. Moreover, in many forest soils, pH is the main factor which determines the length of metal residence at the surface of the soil [36]. In addition, the present investigations exhibited lower pH values in the A0 horizon of the coniferous forest than in the deciduous whilst the general decrease in pH values toward outer profiles suggest its influence on metal mobility and their downward translocation. These results agree well with the metal enrichment factors obtained, particularly for the outer parts of heaps where the strata of waste material are thin and the buffer capacity of the carbonate material is the lowest. Apart from the pH of soils and their buffering properties, the observed Cd, Zn and Pb migration may result from their very high concentrations combined with the limited capacity of sorption complexes. It may also be related to lithology, particularly the presence of permeable sands of former soils, which are underlain by weakly permeable loans in most profiles. It is also worth noting that Pb mobility can be higher in neutral than in acidic soils than Zn and Cd, and it may migrate in the colloidal form [37].