Introduction: Intensive agriculture, coupled with the increased use of mineral fertilizers and pesticides and mechanization, has led to the increasing use of fossil fuels over many decades. In modern agriculture today, in addition to the direct use of fossil fuels in production processes, very high fossil energy inputs are required for the production of capital and consumer goods, especially for the production of mineral nitrogen fertilizers, which account for more than 50% of the total energy input Agricultural production still relies heavily on fossil energy consumption at almost every stage of production. However, there are many approaches to saving fossil energy. Sustainably feeding a rapidly growing population, despite the limited and relatively rapidly decreasing access to arable land, is a major challenge for today's farmers. Meanwhile, increasing crop productivity from existing cropland and reducing environmental impacts are critical strategies to address this challenge. Significant gains in crop productivity have so far been achieved mainly by increasing chemical fertilizers in many regions
Materials and methods: In 2018-19, 25 farms were surveyed using a random sampling method to assess fuel consumption, energy, and greenhouse gas emissions in the cultivation and production of wheat and potatoes in Gorgan County. The required data were collected through face-to-face interviews with producers of these products and taking notes on all agricultural operations. After recording the aforementioned information in each farm, an energy flow assessment was performed. Direct and indirect energy were also calculated. The energy consumption of fuel, human power, use of tools and machinery, pesticides, chemical fertilizers, and seeds were calculated based on the relevant coefficients.
Results: According to the results, 164 and 205 l fossil fuel were required to produce each hectare of wheat and potatoes. Also, 18276 and 40844 MJ/ha energy were consumed to wheat and potato production, respectively. The amount of energy output was obtained for wheat and potato as equivalent to 108000 and 108000, respectively. Accordingly, the ratio of energy output to input was calculated as 0.97 and 2.64.0, respectively. Also, the net energy in wheat and potato was evaluated as 36114 and 67156 MJ/ha, respectively, the energy efficiency was evaluated as 0.2 and 0.73, respectively, and the specific energy was evaluated as 5 and 1.37, respectively.
Conclusion: The results of net energy in wheat and potato were evaluated as 36114 and 67156, respectively, energy efficiency was evaluated as 0.2 and 0.73, respectively, and specific energy was evaluated as 5 and 1.37, respectively. Finally, according to the results obtained, it can be said that the use of chemical fertilizers, especially nitrogen fertilizers, as well as the use of fossil fuels accounted for an important part of energy consumption, and by optimizing their use, an important step can be taken in reducing energy consumption for the production of wheat and potato products. |