Seyede Tayyebeh Hosseini; Hossein Sharifan; َAlireza Kiani; Noormohammad Abyar; mohammad taghi Feyzbakhsh
Abstract
Energy efficiency is one of the most important factors for sustainable agriculture. This study explored the energy consumption and global warming potential for puddled transplanted (PTR), un-puddled transplanted, and direct-seeded rice (Oryza sativa L.) (DSR) production systems under sprinkler, flood, ...
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Energy efficiency is one of the most important factors for sustainable agriculture. This study explored the energy consumption and global warming potential for puddled transplanted (PTR), un-puddled transplanted, and direct-seeded rice (Oryza sativa L.) (DSR) production systems under sprinkler, flood, and drip irrigation systems in Gorgan City fields, Golestan Province, Iran. According to the results, the average energy input and output for different irrigation systems in puddled transplanted treatment was higher than the other treatments, while the highest input and output energy was related to drip irrigation system (36366 and 249971 MJ.h-1). The highest energy consumption in different irrigation and cultivation systems was related to water and nitrogen fertilizer. The results also showed that energy use efficiency for different systems ranged from 5.05 to 7.35 kg.MJ-1. Energy use efficiency for pressurized irrigation systems was higher in puddled transplanted treatment and for flood irrigation systems was higher in un-puddled transplanted treatment. Also, the energy productivities of different treatments were between 0.1 to 0.24 kg.MJ-1, while the mean energy efficiencies of PTR and un-puddled transplanted treatments did not differ significantly and were more than DSR treatment. The specific energy and net energy for different treatments ranged from 4.29 to 10.2 MJkg-1 and 112784 to 213825 MJ.ha-1, respectively. The puddled transplanted treatment had the highest GWP for all irrigation systems. The largest share of GWP in rice cultivation was related to the use of nitrogen fertilizers, fuels, and machinery. The results of mean comparison of GWP per unit area, weight, input energy, and output energy showed that modern pressurized irrigation systems with un-puddled transplanted cultivation method (due to less input and a yield similar to PTR) can be a suitable method for rice cultivation to reduce energy consumption and global warming potential.
T H; M KH; M Z; A GH
Abstract
Crop models are suitable for simulation of crop yield by different scenarios of deficit irrigation and salinity. In this research, the AquaCrop model was evaluated to simulate the soybean grain yield and biomass under different levels of salinity and deficit irrigation in Gorgan County during 2011 and ...
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Crop models are suitable for simulation of crop yield by different scenarios of deficit irrigation and salinity. In this research, the AquaCrop model was evaluated to simulate the soybean grain yield and biomass under different levels of salinity and deficit irrigation in Gorgan County during 2011 and 2012 growing seasons. The model was calibrated by experimental data of 2011 and validated with data of 2012. The experiment included three irrigation levels of 100%, 75% and 55% water requirement and three salinity levels of 0.7, 5 and 10 dS/m. Statistical indices of the results of validated model including RMSE, E, and d for grain yield were 0.225 ton/ha, 0.88 and 0.97, respectively, and for biomass, they were 0.718 ton/ha, 0.77 and 0.95, respectively. Results showed that grain yield decreased with decrease in the amount of irrigation water and increase in salinity level. Further analysis showed that the sensitivity of AquaCrop model to the canopy decline coefficient (CDC) was more than the other parameters at senescence and maximum canopy cover stages.