Shirali Kohkan; Seyed Ahmad Ghanbari; Mohammad Reza Asgharipour; Barat Ali Fakheri
Abstract
This study was conducted using the emergy analysis approach in wheat production systems in order to plan and manage the major challenges facing the Sistan region's wheat production. All inputs for wheat production, the most important crop in the region, were assessed in this study. These inputs include ...
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This study was conducted using the emergy analysis approach in wheat production systems in order to plan and manage the major challenges facing the Sistan region's wheat production. All inputs for wheat production, the most important crop in the region, were assessed in this study. These inputs include renewable inputs, such as sunlight, wind, and rain; nonrenewable inputs, such as soil erosion; and purchased inputs and services, such as machinery, fossil fuels, electricity, labor, nitrogen, potassium, phosphorus, and chemical fertilizers. According to the results of the study, the total emergy production of wheat was 1.061016 sej ha-1. The irrigation water consumed the most energy at 28.96%, followed by nitrogen and phosphorus fertilizers at 20.75 and 16.5%, respectively. The emergy yield ratio index was 1.41, the emergy investment ratio index was 2.4, the environmental loading ratio was 2.41, and the emergy sustainability index was 0.585, which indicates the average sustainability and environmental load of this system relative to other researchers' reports. By increasing input efficiency by optimizing the consumption of irrigation water, nitrogen fertilizer, and phosphorus fertilizer, this production system can be made more sustainable and less taxing on the environment.
Ghasem Gheicari; Mohammad Reza Asgharipour; Mohsen Mousavi Nik; Ahmad Ghanbari
Abstract
Conventional tillage methods result in resource waste and the release of greenhouse gases into the environment. An experiment with a randomized complete block design and three treatments in four replications was conducted at Darab Agricultural Research Station for five years to determine the effects ...
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Conventional tillage methods result in resource waste and the release of greenhouse gases into the environment. An experiment with a randomized complete block design and three treatments in four replications was conducted at Darab Agricultural Research Station for five years to determine the effects of different tillage methods on nitrous oxide (N2O) and ammonia (NH3) emissions in cotton-wheat rotation. Direct farming (no tillage), low tillage, and conventional wheat-cotton tillage (control) were used as treatments. Following wheat harvesting in the direct and low tillage treatments, 30% (weight) of wheat residues were dispersed on the field. Within two years, N2O and NH3 emissions from the cotton-wheat field were estimated using the DNDC 9.5 model. Data from the first three years of the study was used to validate the model. The results of model validation revealed that the model performed well in simulating the soil environment as well as N2O and NH3 emissions. The simulation results revealed that the highest and lowest N2O emission rates occurred in conventional and no-tillage treatments, with a significant difference. After five years of experimentation, average annual N2O emissions were 4.40, 2.80, and 2.14 kg N ha-1 y-1 for conventional, low, and no-tillage treatments, respectively. According to the simulation results, peak NH3 emission from soil occurred on the fifth day after fertilization in all three treatments. The overall findings of this study indicated that the use of no-tillage methods is more advantageous than other cotton culture treatments in cotton-wheat rotation under similar conditions as in the current study.
