Carbon and Nitrogen Sequestration in Coal Mine Soils Amended with Poultry Manure and Paper Mill Sludge.

Two prominent environmental problems in Pennsylvania include abandoned coal mines and excess animal manure production. A field experiment in Schuylkill County, Pennsylvania, is testing two approaches to stabilizing nutrients in poultry layer manure used for mine reclamation: composting and adding paper mill sludge to fresh manure. This field study will determine the carbon and nitrogen sequestration potential of these approaches. Treatments include a lime and fertilizer control, two rates of composted poultry manure (78 and 156 Mg ha^-1 dry weight), and two blends of fresh poultry layer manure (50 Mg ha^-1 dry weight) mixed with paper mill sludge (103 and 184 Mg ha^-1) to achieve C:N ratios of 20:1 and 30:1. In the field, a pulse of NO₃-N from the two rates of poultry manure and paper mill sludge blends occurred in September of each year, with concentrations of 170 and 234 mg N L^-1, respectively, in the first year. Compost treatments showed no such pulse. While manure/paper mill sludge treatments have lost more cumulative labile N over two years, they have still retained 94% and 86% of N originally added in the 20:1 and 30:1 C:N ratio treatments, respectively. Compost treatments have sequestered almost all added N; the control has only retained about 78% of N originally added. Organic treatments sequestered greater C than the inorganic control and provided superior revegetation results. Results of this research will help establish appropriate manure-based reclamation rates by quantifying the fate and flux of carbon and nitrogen, with application in nutrient trading programs.