Comparison of input and output energy and global warming potential in rainfed wheat and barley in Aq-Qala (Golestan province)

In recent years, energy consumption in agriculture has increased dramatically, and modern agriculture has high energy consumption. Most of the energy used to produce agricultural products is spent due
to the use of inputs such as machinery, fossil fuels, fertilizers, and pesticides. Inappropriate use of these inputs
reduces energy efficiency in production and also causes problems for human health and the environment. At
present, due to the energy crisis in the world, it is necessary to study more about energy consumption and find
solutions for its optimal use. This study was conducted to identify the energy evolution and global warming
potential in wheat and barley production in northern lands of Gorgan Plain, city of Aq-Qala, so that appropriate
strategies can be carried out to prevent the waste of energy and reduce the environmental impact of resources. For this study, 95 and 83 farmers were selected for interviewing about wheat and barley production in Aq-Qala city, respectively. The data including machines, seeds, fertilizers, fuel, and pesticides were collected by questionnaire. Then fuel, input and output energy, energy evaluation indices and global warming potential (kg CO2 ha-1) were calculated by related coefficients. The results showed that the highest direct input energy in wheat and barley production belonged to fuel consumption with 38.8 and 46.8 percent, respectively. Also, the highest indirect input energy was obtained from nitrogen fertilizer with 31.3 and 19.1 percent for wheat and barley fields, respectively. The ratio of the output/input energy for rainfed wheat and rainfed barley were calculated 5.01 and 5.03, respectively. Also, global warming potential in wheat and barley production was 943.9 and 739.1 (kg eq-CO2 ha-1), respectively. Also, the results showed that increased fuel and fertilizer consumption will increase the amount of input energy in both crop production and also increase the production of greenhouse gases. Therefore, the use of more efficient machinery and equipment that reduces fuel consumption and also proper crop rotation and using organic fertilizers can increase energy efficiency and reduce the global warming potential of rainfed wheat and rainfed barley production. The results showed that the fuel consumed in both products had the highest input energy, followed by the fertilizer, especially nitrogen fertilizer. Therefore, it is recommended that the reduction of fuel consumption be done by using combinators and protection culture systems (minimum tillage). It is also recommended to apply crop rotation and rotation with covered crops that are able to stabilize nitrogen to reduce the use of fertilizers. It is suggested that the yield increases by improving management operations, optimum use of fertilizers, pest control, which in turn will improve energy efficiency.