Stabilized Organic Carbon in Age-Chronosequence of Reclaimed Mined Soils of Eastern Ohio.

Surface mining for coal drastically alters soil properties, destabilizes soil organic carbon (SOC) and depletes SOC pools. Minesoils are characterized by low soil organic matter content, poor physicochemical and biological properties, limiting their quality, capability and functions. Reclamation of these soils restores vegetation cover, soil quality, ecosystem productivity and replenishes SOC pool.  The study was conducted to assess the effects of age since reclamation on SOC pools and different chemically separated C fractions. The SOC fractions were separated by hydrogen peroxide (H₂O₂), disodium peroxodisulfate (Na₂S₂O₈), sodium hypochlorite (NaOCl) and hydrofluoric acid (HF). Both NaOCl and Na₂S₂O₈ removed 20 to 50% of the SOC in the top 0-20 cm soil depth, while in the sub-soil 30-50 cm depth) the oxidized SOC ranged fro 10 to 20%. In contrast, the oxidized SOC under H₂O₂ ranged from 30 to 50% and both soil depth and age since reclamation had no effect on oxidation efficiency. Our results indicate that chemical oxidation methods can be used to fractionate active and stabilized organic carbon in reclaimed mined soils.