|Dutta, Tanushree - PENNSYLVANIA STATE UNIVERSITY|
|Stehouwer, Richard - PENNSYLVANIA STATE UNIVERSITY|
Submitted to: Land Degradation and Development
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/25/2014
Publication Date: 12/4/2014
Citation: Dutta, T., Stehouwer, R.C., Dell, C.J. 2014. Linking organic carbon, water content and nitrous oxide emission in a reclaimed coal mine soil. Land Degradation and Development. 26:620-628.
Interpretive Summary: Amending reclaimed mine-land soils with manures and other organic materials improves soil properties and helps promote plant growth during re-vegetation, but application of large quantities of organic material can promote emission of the greenhouse gas nitrous oxide. The effect of several organic amendments on nitrous oxide emissions were tested in a laboratory study. While uncomposted manure produced the greatest emissions, no more the 0.1% of the nitrogen content of the any of the amendments was emitted as nitrous oxide. The study demonstrated a relatively low potential risk for greenhouse gas production when these amendments are used for mine-land reclamation.
Technical Abstract: Manure-based organic amendments can restore soil quality and allow for intensive sustained biomass production on degraded lands. However the large quantities of nitrogen and organic carbon added with such amendments could create soil conditions favorable for nitrous oxide production and emissions. To investigate this possibility, we conducted a laboratory experiment using mine soil collected from an active surface coal re-mining site near Philipsburg, Pennsylvania. During a 37 d incubation period, we measured nitrous oxide and carbon dioxide fluxes from unamended soil and from soil amended with ammonium nitrate (L+F), composted poultry manure (Comp), poultry manure alone (Man) and mixed with 3 rates of paper mill sludge (PMS) to obtain carbon to nitrogen ratios of 14, 20 and 27 (Man+PMS 14, 20 and 27), each at 60% and 80% water filled pore space (WFPS). Results showed that manure alone had a greater potential for emissions than L+F. However, composting manure effectively reduced that potential to that of L+F despite addition of a lot of organic C and N. Composted manure-treated soil emitted less than all other manure-based treatments at both 60% and 80% WFPS. A greater potential for nitrous oxide emission was observed from soil amended with the Man+PMS treatments compared to non-amended and L+F-amended soil. This potential increased during periods of intense microbial activity created by the application of manure and PMS. Higher water content increased emissions particularly during periods of intense microbial activity coupled with inorganic nitrogen availability. Cumulative soil nitrous oxide emissions from manure-treated soils represented less than 0.1% loss of total applied nitrogen. The highest nitrous oxide emission obtained from the Man+PMS treatment was only about 0.1% of total applied N and 5% of applied ammonium-nitrogen.