## 3 Results
The low values of diversity (H\({}^{\prime}\) = 0.10; M = 0.44) and equitability (J = 0.09) of the MOD community together with the uneven distribution of dominances in the community and the fact that no individual was found in the MOS substrate indicate extremely disturbed soils close to the ash pond. Despite the higher values of diversity in the natural soils at MOM and MOF sites than in the ash pond and its dam, we cannot consider the mite community's state optimal. [PERSON] et al. [51] reported much higher diversity (H\({}^{\prime}\) = 4.60: 4.19; M = 11.75: 9.74), even though there was lower equitability (J = 0.33: 0.27) in the various meadow and forest soils across Northern Slovakia. Similar values of H\({}^{\prime}\) diversity were recorded for ruderal habitats and less managed urban parks (2.72: 2.27), where lower values of equitability (J = 0.48: 0.41) and higher values of diversity were also recorded (M = 12.90: 10.73) [52]. The oribatocoenoses of MOM and MOF can, thus, be considered as balanced, species-poorer communities. The correlation analysis outlined that the abundance and diversity of oribatid mites increase with decreasing the substrate's pH. There was a positive correlation between mite abundance and diversity and soil moisture, and the same was observed with soil microbial respiration. Interestingly, the highest was the soil carbon-to-nitrogen rate and the lowest was mite diversity and abundance. We also found a negative correlation with mite abundance and increased arsenic, nickel, cobalt, and chromium concentrations. The risk elements demonstrably negatively affected mite diversity, primarily cobalt and nickel (Table 4). The interrelationships between species and coenoses, shown by cluster analysis (Figure 3), divided the oribatid mite community into three basic clusters. The Cluster A included species reaching an eudominant and dominant position in the MOM and MOF sites, predominantly freely passing between sites, except for _P. pelifier_, _O. ([PERSON]) [PERSON]_, _S. laevis_, and _Sheliorbates pallidulus_ ([PERSON], 1841), which achieved a high dominance in only one of these sites. The Cluster B included species bound to the MOF site, preferring a forest-habitat type, of which only _O. (M.[PERSON]_ occurred in a recent position at the MOD site. Grouping C represented a recent to subrecent species bound mainly to the meadow character of the MOM locality. Species _Punctoribates punctum_ ([PERSON], 1839) and _Xenillus tegeocranus_ ([PERSON], 1804) had a similar position MOF locality. _P. italicus_ and _T.v. sarekensis_, occurring at the MOD site, did not belong to any of the mentioned clusters; moreover, their joint occurrence appeared to be accidental (Figure 3). \begin{table}
\begin{tabular}{c c c} \hline  & **A** & **D** \\ \hline pH & \(-\)0.92 ** & \(-\)0.98 * \\ w & 0.84 * & 0.91 ** \\ MBC & \(-\)0.66 ** & \(-\)0.58 ** \\ SMA & 0.88 ** & 0.96 * \\ C/N & \(-\)0.86 ** & \(-\)0.96 * \\ As & \(-\)0.96 * & \(-\)0.86 ** \\ Cu & ** & \(-\)0.59 ** \\ Ni & \(-\)0.84 ** & \(-\)0.96 * \\ Co & \(-\)0.73 ** & \(-\)0.91 ** \\ Ba & ns & \(-\)0.63 * \\ Cr & \(-\)0.65 ** & \(-\)0.85 ** \\ \hline \end{tabular}
\end{table} 
Table 4: The correlation between chemical and microbiological attributes and oribatid mites’ diversity and abundance. A, mite abundance; D, mite diversity; pH (H\({}_{2}\)O/KCl), negative log of the hydrogen ion concentration; w, water content in the sample; MBC, microbial biomass carbon (dry weight); SMA, soil microbial activity (respiration); C/N, total organic carbon-and-nitrogen ratio. Significance labels: * \(p\) < 0.01; ** \(p\) < 0.05; ns, non-significant.