Greenhouse gas and ammonia emissions in modelled cereal crop production under Polish agricultural conditions: An example spring barley

Based on the analysis of statistical data, the average area under cultivation and average yields of barley in Poland in 2010–2020 were calculated. Barley is one of the most important cereals grown in Poland. Its cultivation area occupied an average of 920,595 ha in these years, with average yields of 3.66 Mg∙ha−1. Barley is a cereal grown mainly as a spring cereal. The average area under spring species in these years accounted for 95% (875,771 ha) of the total area under this cereal, and the average yield of spring varieties was 3.60 Mg∙ha−1. In order to estimate emissions of greenhouse gases (GHG) and ammonia (NH3), the sources of emissions – inorganic fertilisers, fuel consumption – were analysed for selected barley cultivation technologies, differentiated by yield level, and variant model production technologies were developed to obtain projected yields. Emissions were calculated for individual greenhouse gases (N2O, CH4 and CO2) and they were recalculated according to the greenhouse potential of each gas (GWP – global warming potential) to be able to compare the total amount of greenhouse gas emissions for the analysed variants. Greenhouse gas emissions for cultivation technology ranged from 134.53 to 136.48 kg CO2eq for 1 Mg yield. A more accurate Tier 2 method was used to estimate NH3 emissions, taking into account soil conditions and climate zone. The estimated ammonia emissions from the application of mineral fertilisers were from 0.99 kg to 2.35 kg for 1 Mg yield.