Surface Coal Mine Soils: Evidence for Chronosequence Development

Anthropogenic changes to soil properties and development can dominate systems, particularly in coal mining-impacted landscapes of the Appalachian region United States. Historical mining operations deposited spoils which are developing into mine soils chronosequences, allowing for a correlation between emplacement age rates change properties. The study site was Huff Run Watershed (Mineral City, OH, USA) with series eleven spoil piles that were over 30-year time period. Surface analyzed bulk density, loss on ignition (LOI) as proxy organic matter, particle size, mineralogical (by X-ray diffraction) elemental fluorescence) compositions. following linear trends observed across transect from older younger soils: density increased 1.0 cm−3 1.5 g cm−3; LOI decreased ~20% 5%; content sand-sized particles quartz ~50% 30% 50% 25%, respectively, corresponding increase contribution clay mineral ~25% 60%; Fe other trace metals (Cu, Ni, Pb, Sb, Sn, Te) concentration, while Al, Mg, K concentration. These likely result of: (1) matter accumulation vegetation becomes more abundant time; (2) transport clays out recently emplaced waste; (3) oxidative dissolution primary sulfides releasing followed by re-precipitation secondary Fe-phases metal sequestration. findings presented here provide insight future behavior these materials potentially be used assess inferred previously unexamined wider geographic area. results also inform decisions related reclamation activities ecosystem restoration.