Future study of energy use efficiency in irrigated wheat production in eastern Urmia lake

Introduction:
In all countries, agricultural production is dependent on energy, especially fossil fuels. About 10 to 20 percent of the total energy used in developed countries is consumed in food production. Efficient use of energy in the agricultural sector is one of the fundamental necessities for sustainable agriculture development, because increasing energy efficiency will save fossil fuels and reduce air pollution. In addition, the global energy crisis and the need for targeted energy consumption in agricultural production make the research on energy efficiency analysis in wheat production necessary. Energy efficiency values in wheat production in the east of Urmia Lake have not been assessed so far. Therefore, the present study was conducted with the aim of evaluating future research of energy indices, including net energy, energy efficiency, specific energy, and energy productivity as well as providing suitable and applicable solutions for improving energy indices in wheat production.
Material and methods:
In this research, energy productivity in two conservational and conventional tillage systems in wheat production in the east of Urmia Lake was evaluated for two years by measuring and collecting data. Energy indices such as net energy, energy efficiency, specific energy, and energy efficiency were determined in wheat production. According to the current conditions of Lake Urmia, water resources were limited and, therefore, the value of irrigation water was significant from the environmental and economic point of view. Consequently, in order to rebuild future conditions of energy consumption in wheat production, irrigation scenarios were applied as a future study strategy. Irrigation management scenarios included three conditions of full, deficit and excessive irrigation in wheat farms.
Results and discussion:
Energy productivity from conservational and conventional tillage systems were 210 and 170 g MJ-1, respectively. Future study scenarios were comprised of three conditions of full, deficit and over-irrigation in wheat farms. The energy consumed to produce wheat with the first (full and over-irrigation) and second (deficit irrigation) scenarios were 18.5 and 17.7 GJ ha-1, respectively. The energy produced of wheat grains by the first and second group scenarios was respectively 67.5 and 31.8 GJ ha-1. The average energy efficiency in grain production with first and second groups was 3.7 and 1.8 and energy productivity was 253 and 125 g MJ-1, respectively. The effective strategies for increasing energy productivity in wheat production in the northwest of the country may include the application of light-weighted machinery, selection of the appropriate amount of seeds, and enhancement of fertilizer and water use efficiency.
Conclusion:
Results revealed that in terms of energy indices, the application of the conservational tillage system is preferable over conventional tillage in wheat grain production. However, the energy indices by two tillage systems were not statistically different in wheat production. It seems that the appropriate practices of conservation tillage by appropriate selection of equipment would improve the energy indices in wheat production.