Energy flow analysis for rice production in different geographical regions of Iran

• There was a significant difference among the three provinces in respect to energy ratio.
• Results demonstrated that energy use is not efficient.
• On average 84.70% of total energy input used in rice production was non-renewable.
• The results confirmed the importance of diesel fuel and chemical fertilizer consumption on total energy input.

Rice (Oryza sativa L.) is an important primary crop in Iran. In this study, energy use pattern for rice production was analyzed and compared in different geographical regions, Golestan, Mazandaran and Guilan, northern provinces of Iran. There is a significant difference among the three provinces in respect to input energy and agronomical managements such as crop rotation, transplanting date and land preparation. Data were collected from 50 farmers using a face to face questionnaire-based survey. The data collected belonged to the production period of 2012–2013 with the following results obtained. The energy use efficiency varied from 1.39 for Golestan to 1.67 for Guilan provinces. The research results revealed the main difference between energy consumption in three provinces comes from diesel fuel, chemical fertilizers and electricity. The net energy for paddy production was approximately higher in Guilan (36,927.58 MJ ha−1) than other provinces. Also, the values of energy productivity (kg MJ−1) for Golestan, Mazandaran and Guilan provinces were found to be 0.064, 0.059 and 0.070, respectively. On average 84.70% of total energy input used in rice production was non-renewable, while the contribution of renewable energy was 15.30. The results showed that the total energy input for rice production in Golestan province was 64,158.78 MJ ha−1 which was higher than other provinces, due to high energy consumption in diesel fuel style (46.44%).