عنوان مقاله [English]
In order to evaluate the greenhouse gases emission in wheat, barley and maize production of Iran, this study was conducted. The data was collected for 5 years (2006-2011). Data collected included the amounts of fertilizers (N, P and K), herbicides, insecticides and fungicides used, human labor, diesel fuel, and total yield for each crop. Result showed that the total carbon emission of wheat, barley and maize production systems were 6454.67, 4339.95 and 8722.8 kg CO2-equivalent per hectare respectively. Leaching of nitrogen fertilizers and diesel fuel were the most important pollutants of environment in terms of carbon emission in these crops. The result also showed that maize had a lower carbon footprint (0.42) than wheat (0.52) and barley (0.58). Totally maize farming system in Iran was more efficient than wheat and barley farming systems in terms of CO2-equivalent indices. Finally, increasing the water and fertilizer use efficiency of farms and replacing the conventional tillage with conservation tillage or no-tillage would be useful for reducing carbon footprint and therefore improvement of the agricultural sustainability in Iran.