Maximizing Carbon Sequestration in Coal Mine Soils with Different Amendments as Determined by 13 C Abundance.

Disturbed soils such as mine soils have the capability to sequester carbon by acting as a carbon sink through the formation of soil organic matter.  Reclamation of these soils can capitalize on this potential. To understand the fate of carbon in reclamation projects, carbon additions and losses must be tracked; however, mixing of coal and other geologic material containing carbon within soil samples may lead to overestimation of carbon additions to the soil. By tracing the natural abundance of ¹³C, a more accurate account of carbon fate could possibly be obtained. A four year study in Pennsylvania is utilizing natural ¹³C abundance as a tracer for carbon additions during reclamation of mine soils.  Amendments such as poultry manure mixed with paper mill sludge and compost will be assessed for their suitability in facilitating carbon sequestration. Preliminary data shows that unamended soils have δ¹³C values averaging -25.1‰ while soil compost averaged -24.8‰ and manure/paper mill sludge averaged -24.65‰. In addition the difference between C3 (δ¹³C average -26‰) and C4 (δ¹³C average -13‰) plants in natural ¹³C abundance can help explain carbon additions that occur from switchgrass (a C4 species) production in the mine soils that were previously occupied by native C3 vegetation.