Prediction of Nitrous Oxide (N₂O) Emission Based on Paddy Harvest Area in Lampung Province Indonesia using ARIMA on IPCC Model

Agricultural are significant sources of N2O emission. Lampung, Indonesia is an area dominated by agriculture including crops that emit N2O on their cultivation practices especially the fertilizers: paddy and vegetables. Last census in 2015 recorded that paddy fields were 1.321.120 ha and vegetables 99,284 ha with fertilizers recommendations were 200 kg/ha urea (without organic materials) and 150 kg/ha urea (if added with 2 tons/ha manure). This study aimed to estimate and predict N2O emissions based on the paddy field area using IPCC 2006 model. The IPCC model was applied to the paddy field data 1993 to 2012 from the Indonesian Ministry of Agriculture to estimate the N2O emission and then using Box Jenkins model to predict the emission for following years. The results showed that the prediction of N2O emission on the following years would be in the range of 0.282- 0.451Gg/year using only synthetic fertilizer and if added with organic fertilizers would be 5,846-9,359 Gg/year. These results were lower compared to some countries; however, this result was not implied that fertilizer recommendations in Lampung were safe since the results came from default numbers of the model. More researches should be conducted that local emission factors would be available that fertilizer recommendation could be evaluated.