Energy Consumption Pattern and Sensitivity Analysis of Irrigated Wheat Production Farms in Kermanshah

The objectives of this study were to evaluate the energy consumption and greenhouse gas emissions and to determine the input sensitivity for wheat the production system in Kermanshah County, Iran. To achieve these objectives, data were collected from120 irrigated wheat farms selected during 2012 using a random sampling method. The sensitivity of the energy inputs was estimated using the marginal physical productivity (MPP) method and partial regression coefficients on wheat yield. The results indicated that the total energy input was 41,921.8 MJ ha-1, of which approximately 38% and 13% were from nitrogen fertilizers and diesel fuel, respectively. Approximately 57% of the total energy inputs used in wheat production was direct energy, while the remaining 43% was indirect. Total emissions of CO2, N2O and CH4 in alfalfa farms were 1248.1, 855.6 and 1.6 kg ha-1, respectively: Hence, total GWP was 266525 kg CO2e ha-1 and 68.1 kg of CO2e kg-1 of wheat grain produced. The econometric assessment results revealed that the energy inputs of human labour, machinery, diesel fuel, chemical fertilizers had a significant influence on yield. Sensitivity analysis indicated that the MPP value for energy inputs was between -2.8 and 11.31. Also, the MPP value for human labour was the highest, followed by machinery, water for irrigation and phosphorous fertilizer energy inputs, respectively. However, the MPP for biocide energy was calculated as -1.97, implying that the use of biocide energy is excessive in wheat production, causing a problem of environmental risk in the region. Direct, indirect, renewable, and non-renewable energy forms had positive impacts on the output level.