Nitrous Oxide Emission From Coal Mine Reclaimed with Organic Amendments.

Surface coal mining causes drastic soil disturbances leading to serious disruption of soils inherent characteristics and productivity. Reclamation of mined lands must restore their capacity to support vegetation and other essential ecosystem services. Organic amendments such as manure, composted manure and industrial byproducts are effective in restoring soil productivity; however these has been little investigation of the potential for these amendments to give rise to nitrous oxide (N₂O), a potential greenhouse gas. In an initial assessment of such N fluxes we conducted a 15 day laboratory incubation experiment to compare N₂O fluxes from mine soil amended with fresh poultry manure, composted layer manure and manure mixed with paper mill sludge. This experiment was carried out in two soil moisture conditions, one when the soil water holding pore space (WHPS) was maintained at 60% and the other in 80% WHPS to be able to correlate such emissions with the soil moisture conditions. Fluxes from the soils treated with the organic amendments were compared to N₂O fluxes from conventional lime and fertilizer amendment. Besides, we conducted a potential denitrification measurement experiment to obtain an idea of maximum N₂O output that can occur when the soil conditions are optimum for denitrification. The experimental outcomes from both these incubation studies led us to draw some conclusion on the overall effects of using these amendments for mine land reclamation which will be presented upon which an estimate will be made on the impacts these treatments are going to have on the environment in the long run.