104-13 Fertiliser Formulation Effects on Gross Nitrogen Transformations in Permanent Grassland Soil.

See more from this Division: SSSA Division: Soil & Water Management & Conservation
See more from this Session: Management Impacts on Soil Properties and Soil C and N Dynamics: I

Monday, November 16, 2015: 4:20 PM
Minneapolis Convention Center, M101 A

Mary Harty1, Karen McGeough2, Rachael Carolan2, Karl G Richards3, Patrick J Forrestal3, Christoph Mueller4, Chris Elliott5, Ronnie Laughlin2 and Catherine Watson2, (1)Johnstown Castle, TEAGASC, Wexford, IRELAND
(2)Agri-Food and Biosciences Institute (AFBI), Belfast BT9 5PX, Northern Ireland
(3)Environment, Soils and Land-Use, Teagasc, Wexford, Ireland
(4)Heinrich-Buff-Ring 26, Justus-Liebig Univesity Giessen, Giessen, Germany
(5)Institute for Global Food Security, Queens University Belfast, Belfast, United Kingdom
Abstract:
Agriculture was responsible for almost one third of Ireland’s overall Greenhouse Gas (GHG) emissions in 2012, with 39% of these emissions arising from chemical/organic fertilisers in the form of nitrous oxide (N2O). Ireland has a target to reduce GHG emissions by 20% below 1990 levels by 2020 while increasing the volume of milk produced by 50% in the same timeframe. The contradictory aims of increasing food production while reducing GHG emissions will require an adjustment to the current system of agricultural production. As part of a larger study evaluating the  switching of nitrogen (N) fertiliser formulation to minimise N2O emissions, (from calcium ammonium nitrate (CAN) to urea based formulations), this experiment examined the effect of urea based fertiliser formulations on gross N transformations in a permanent pasture soil from Hillsborough, Co. Down, Northern Ireland.

 

This study used an established grassland soil in a laboratory incubation study, to examine the effect of urea in various combinations with two types of inhibitors on the soil N dynamics and N2O and N2 emissions.  The inhibitors examined were the urease inhibitor N-(butyl) thiophosphoric triamide (nBTPT) and the nitrification inhibitor dicyandiamide (DCD). 15N isotopic labelling was applied to the samples to allow the determination of several simultaneously occurring gross N transformation rates.  Soil mineral N (urea, NH4+ , NO2- and NO3-) concentrations, gaseous losses (N2O and N2) and the 15N enrichments of the NH4+, NO2-, NO3- , N2O and N2 were analysed on 8 separate occasions over 25 days. A numerical 15N tracing model (Müller et al., 2007) was used to quantify gross N transformation rates.  The effect of the inhibitors on gross N transformations, sources of N2O and N2O:N2, emission ratios was analysed.

See more from this Division: SSSA Division: Soil & Water Management & Conservation
See more from this Session: Management Impacts on Soil Properties and Soil C and N Dynamics: I

<< Previous Abstract | Next Abstract