Soil quality indicators for reclaimed minesoils in southeastern Ohio

Soil quality indices are useful for ascertaining temporal changes in soil properties in relation to land use and management, especially for drastically disturbed soils, and for designing the best management systems for minesoil reclamation. Soil quality indices were developed by analyzing physical and chemical properties of the minesoils in Jackson and Vinton counties, Ohio, reclaimed in 1975 and 1976. Soil properties were also assessed for the adjoining unmined soil and the spoil. The principle component analysis (PCA) was performed on 20 physical and chemical soil properties, separately for each experimental site, for 0- to 10-cm depth. The PCA performed with correlation matrix grouped 20 measured soil attributes into four distinct principle components (PCs) for each site. The PCs were related to measured soil properties, based on their communality estimates. The factors identified were (i) bulk density, (ii) water infiltration, (iii) aggregate size, and (iv) soil nitrogen for the Jackson site and (i) bulk density, (ii) water infiltration, (iii) organic carbon, and (iv) porosity for the Vinton site. These factors were assessed with respect to the specific soil functions and were designated as soil quality indicators. The discriminant analysis of retained PCs showed that the bulk density factor was the most discriminating and water stable aggregation the most dominating common measured soil attribute or the dynamic soil quality indicator for both sites. Other soil quality indicators varied in the order soil bulk density > field water capacity > clay concentration. These factors monitored over time are indicators of change in soil quality, whether aggrading, degrading, or stable.