Mr Robert Impraim1, Dr Helen Charlotte Suter1, Dr Anthony Weatherley1, Prof Deli Chen1
1School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University Of Melbourne, Parkville, Australia
Lignite (brown coal), due to its low pH, high cation exchange capacity, pH buffer capacity, labile carbon (C) and humic acid contents, has been shown to suppress the volatilization of ammonia when used as a manure amendment. Though the retention of nitrogen (N) by the lignite enhances the value of the manure as soil amendment, the fates of the retained N and the added lignite C in the amended manure when applied to soil are not well understood. In this ongoing 40-day laboratory soil incubation study, the C and N mineralization rates of cattle manure amended with two different lignite materials are being assessed by determining changes in mineral N (ammonium-N and nitrate-N) concentrations as well as changes in carbon dioxide, methane and nitrous oxide concentrations in the headspace of the incubated soil. We hypothesized that the lignite amended manure would have higher mineralization rates than the unamended manure due to the increased labile C fraction in the former.
Robert Impraim is a PhD student in Agricultural Sciences at The University of Melbourne. His current research interests centre on nitrogen retention in animal waste streams using lignite (brown coal) and the dynamics of composting lignite amended manure.