Energy
H. Eskandari
Abstract
Increasing demand for agricultural products and production of resource constraints- especially the limitation of cultivable areas - have made the highest yield per unit area the main goal of agricultural producers. Agriculture is a system exhibiting high energy consumption and production. Since energy ...
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Increasing demand for agricultural products and production of resource constraints- especially the limitation of cultivable areas - have made the highest yield per unit area the main goal of agricultural producers. Agriculture is a system exhibiting high energy consumption and production. Since energy has a direct impact on the efficiency of crop production, a sustainable agricultural system needs to be analyzed in terms of its input and output energy to determine the total consumed energy of production per unit area. The difference between input and output energy determines energy efficiency of an agronomical system. Input energy requires being well analyzed to reduce energy consumption and increase energy efficiency. This paper reviews energy efficiency indices based on energy consumption during planting and harvesting. To enhance energy efficiency of agronomical systems, some strategies are discussed in detail, including using high quality seeds, minimum tillage systems, direct seeded rice, weeds control especially in irrigation canals and plant nutrition through agronomical management. Although some agronomical strategies -like complementary irrigation in dry land farming systems- increase input energy, they increase crop yield. However, when output energy, resulting from the rise in crop yield, is higher than input energy, the system energy efficiency improves. Still, some inputs cannot be altered according to regional conditions which are often related to harvest stages operations.
Energy
H. Eskandari; S. N. Mosavian
Abstract
This research, conducted in Gotvand, southwest of Iran, compared the energy consumption of two cucumber production systems: field and greenhouse production systems. In this study, energy inputs of two production systems of cucumber (including seed, pesticide, human labor, machinery, diesel fuel, electricity, ...
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This research, conducted in Gotvand, southwest of Iran, compared the energy consumption of two cucumber production systems: field and greenhouse production systems. In this study, energy inputs of two production systems of cucumber (including seed, pesticide, human labor, machinery, diesel fuel, electricity, organic manure, chemical fertilizer) were determined from questionnaires completed by farmers. The results of the experiment indicated that the energy input of the two cultivation systems was not significantly different in input energies. In both cucumber production systems, the most input energy was allocated to nitrogen fertilizer (57% and 53% for field and greenhouse, respectively) followed by diesel fuel (21% in both production systems). Non-renewable energies accounted for 90 and 88% of the total energy input to the farm and greenhouse systems, respectively. Total output energy of field and greenhouse cucumber production system was 33000 and 34000 MJ, respectively. Reducing the consumption of nitrogen fertilizer through the use of appropriate crop rotation is a suitable solution to improve energy efficiency in the cucumber production system.
Energy
H. Eskandari
Abstract
Agriculture is a system exhibiting high levels of energy consumption. Thus, energy analysis is crucial for improving the energy efficiency of agricultural systems. In this research, the input energy of an irrigated wheat production system, including seeds, machinery, fertilizer, irrigation, electricity, ...
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Agriculture is a system exhibiting high levels of energy consumption. Thus, energy analysis is crucial for improving the energy efficiency of agricultural systems. In this research, the input energy of an irrigated wheat production system, including seeds, machinery, fertilizer, irrigation, electricity, diesel fuel and human labour, were determined and thereby the net output energy, energy efficiency and energy productivity were calculated for energetic system evaluation. For reaching this goal, 110 farmers were asked to complete the questionnaires in which cultivation information such as machinery, diesel fuel, grain produced per hectare, cultivation method, the method and the duration of water supply, workers, chemical materials which were used for plant treatment. The results showed that the total input energy for producing irrigated wheat was 42,481 MJ.ha-1. Energy efficiency was achieved as 1.56, suggesting that the total output energy of the system was more than the input energy. The net output energy, indicating the rate of obtained net energy from the system, was 23,819 MJ.ha-1. Electricity and fertilizer were the inputs consuming the most energy in an irrigated wheat production system, in which 41% and 31% of the total consumed energy were devoted to electricity and fertilizer, respectively. Therefore, the appropriate management of electricity and fertilizer through advanced methods of irrigation and the precise calculation of plants’ required nutrient elements can result in the improvement of the energy efficiency of the system. Reducing seed bed preparing operations (decrease diesel fuel consumption) may also increase the energy efficiency of the wheat production system