Comparison of Silage Corn (Zea mays L.) and Forage Sorghum (Sorghum bicolor L.) Productions in Terms of Energy Consumption and Global Warming Potential in Gorgan Region

Document Type : Scientific - Research

Authors

1 Department of Agricultural and Horticultural Research , Agricultural and Natural Resources Research and Education Center of Golestan, Gorgan, Iran.

2 Department of Agronomy, Faculty of Crop Production, Gorgan University of Agricultural Sciences and Natural Resources, Iran

Abstract

Introduction:
Cheap and plentiful fossil energy causes human’s life welfare to improve and increase food production, but today, major problems have been created in fossil fuels. These problems include: scarcity of fossil fuels for future generations, increase in energy prices, and the most importantly, greenhouse gas emissions (such as carbon dioxide, nitrous oxide and methane) from the use of fossil fuels to the atmosphere.
Energy productivity is one of the most important factors for sustainable agriculture. The use of fossil fuels and chemical fertilizers are threatening the environment. The comparing energy consumption by crops is one of the ways to prioritize various agronomic productions in each area.
Materials and method:
To conduct this study, two crops (silage corn and sorghum) were selected. The reason for this choosing was the numerous similarities of these two plants (including similar planting date, farm operation and consumptions). Accordingly interviews with various farmers (15 and 20 farmers was selected to filling in questionnaire for silage corn and sorghum in Gorgan suburb, respectively) required data of machinery and consumables inputs, including seeds, fertilizers, fuel and pesticides were collected.
To estimate the energy consumption of inputs such as fertilizers, pesticides, insecticides amount of energy per gram of active ingredient was multiplied in related coefficients and their density. Other input and output calculations of energy used in production and field operations for each of the methods was calculated using coefficients obtained from various references. After that it was analyzed in three parts, fuel consumption, and consumed fuel and global warming potential based on the carbon dioxide equivalent.
Results and discussion:
The most input energy in silage corn and silage sorghum was 23.2 and 24.7 percent respectively based on fertilizer consumption. Also, the highest direct input energy in corn silage and forage sorghum was 27.3 and 31.4 respectively, related to fuel. The output energy in silage sorghum was more than silage corn, such that the output energy in forage sorghum was 315.56 GJ/ha more than silage corn. The main reason for this observation was the high yield of forage sorghum fields. The ratio of output to input energy in spring corn and forage sorghum were calculated 4.3 and 15.6 respectively. In other words, energy efficiency was higher in silage sorghum farms and this was due to the higher yield and lower inputs in the crop. The energy efficiency in corn silage was less than silage sorghum, the reason was low yield per unit area (12.500 kg of dry matter per hectare) and more energy input in silage corn farms. In both crop the highest global warming potential (GWP) was related to nitrogen fertilizer and fuel consumption. The highest and the lowest global warming potential respectively observed in silage corn and forage sorghum (with 1845.9 kg CO2/ha and 1729 kg CO2/ha). Consumption of agricultural inputs such as herbicides and pesticides was lower in silage sorghum farms. In both the least amount of greenhouse gas emissions related to fertilizer potassium was 39.5 kg CO2 equivalent.
Conclusions:
The energy input and greenhouse gas emissions in spring corn were higher than forage sorghum due to more agricultural operations (such as herbicides and pesticides consumption), in this respect the cultivation of forage sorghum had minimal environmental impacts. In both crops the consumption of fuel and fertilizer constitute the high percentage of energy consumption and greenhouse gas emissions. Therefore, the use of devices that reduce fuel consumption is recommended, also need for research and investigation on crop rotation and nitrogen fixing plants was revealed. Comparison of the global warming potential (GWP) based on the unit weight yield per hectare of silage sorghum and silage corn showed that there are very significant differences between the two crops, so that global warming potential of the spring corn planting was 12.1 times higher than that of silage sorghum.

Keywords


Akcaoz, H., Ozcatalbas, O., and Kizilay, H. 2009. Analysis of energy use for pomegranate production in Turkey. Journal of Food, Agriculture and Environment 7: 475-480.
Amanloo, A., and Ghasemi Mobtaker, H. 2013. Energy balance and sensitivity analysis of inputsfor forage maize production in Iran. International Journal of Agriculture and Crop Sciences 5(4): 377-384.
Broumand, A, Aghkhani, M., and Sadrnia, H. 2014. A comparison of utilization systems in terms of energy consumption of soybean production in Moghan region. Journal of Agroecology 6: 905-915. (In Persian with English Summary)
Canakci, M., Topakci, M., Akinci, I., and Ozmerzi, A. 2005. Energy use pattern of some field crops and vegetable production: Case study for Antalya region, Turkey. Energy Conversion and Management 46: 655-666.
Clements, D.R., Weise, S.F., Brown, R., Stonehouse, D.P., Hume, D.J., and Swanton, C.J. 1995. Energy analysis of tillage and herbicide inputs in alternative weed management systems. Agriculture, Ecosystems and Environment 52: 119-128.
Dastan, S, Soltani, A, Noormohamadi G., and Madani H. 2014. CO2 emission and global warming potential (GWP) of energy consumption in paddy field production systems. Journal of Agroecology 6: 823-835. (In Persian with English Summary)
Feyzbakhsh, M.T., and Soltani, A. 2013. Energy flow and global warming potential of corn farm (Gorgan City). Electronic Journal of Crop Production 6(2): 89-107. (In Persian with English Summary)
Franzluebbers, A.J., and C.A, Francis. 1995. Energy output-input ratio of maize and sorghum management systems in Eastern Nebraska. Agriculture, Ecosystems and Environment 53: 271-278.
Ghorbani, R., Mondani, F., Amirmoradi, S., Feizi, H., Khorramdel, S., Teimouri, M., Sanjani, S., Anvarkhah, S., and Aghel, H. 2011. A case study of energy use and economical analysis of irrigated and dryland wheat production systems. Applied Energy 88:283-288. (In Persian with English Summary)
Guo, J.H., Liu, X.J., Zhang, Y., Shen, J.L., Han, W.X., and W.F, Zhang. 2010. Significant acidification in major Chinese croplands. Science 3: 1008-1010.
Hydrocarbon Balance Sheet of Country. 2008. Department of Energy Management Institute for International Studies. http://www.iies.org.
Kazemi, H. 2014. Energy flow evaluation of soybean fields in Golestan province. Iranian Journal of Oilseed Plants 3(1): 13-27. (In Persian with English Summary)
Koocheki, A. 1994. Agriculture and Energy. Ferdowsi University of Mashhad Press, Mashhad, Iran 145 pp. (In Persian)
Lorzadeh, S.H., Mahdavidameghani, A., Enayatgholizadeh, M.R., and Yousefi, M. 2012. Reasearch of energy use efficiency for maize production system in Izeh, Iran. Acta Agriculturae Slovenica 99: 137-142.
Mokhtarpour, H. 2011. Impact of planting date and density on growth of maize in northern Iran. PhD thesis. Serdang: University Putra Malaysia Publications 268 pp.
Nasirian, N., Almasi, M., Minaee, S., and Bakhoda, H. 2006. Study of energy flow in sugercan production in an agro-industry unit in south of Ahvaz. In Proceeding 4th National Congress of Agricultural machines. Tabriz, Iran, 11-14 March. (In Persian)
Nikkhah, A, Emadi, B, Shabanian, F., and Hamzeh-Kalkenari, H. 2014. Energy sensitivity analysis and greenhouse gas emissions for tea production in Guilan province. Journal of Agroecology 6: 622-633. (In Persian with English Summary)
Ozkan, B., Akcaoz, H., and Fert, C. 2004. Energy input-output analysis in Turkish agriculture. Renew. Energy 29: 39-51.
Pimentel, D. 1992. Energy inputs in production agriculture. In R.C. Fluck, Energy in World Agricultur 6: 13-29.
Pishgar Komleh, S.H., Keyhani, A., Rafiee, S., and Sefeedpary, P. 2011. Energy use and economic analysis of corn silage production under three cultivated area levels in Tehran province of Iran. Energy 36: 3335-3341.
Rahimizadeh, M., Madani, H., Rezadust, S., Mehraban, S., and Marjani, A. 2007. Energy analysis of agricultural ecosystem and Strategies to increase energy efficiency. 6th National Conference on Energy, Tehran, Iran, 10-13 June. (In Persian)
Rathke, G.W., Wienhold, B.J., Wilhelm, W.W., and Diepenbrock, W. 2007. Tillage and rotation effect on corn–soybean energy balances in eastern Nebraska. Soil and Tillage Research 6: 245-261.
Ren, T.L., Liu, Z.X., Wei, T.Y., and Xie, G.H. 2012. Evaluation of energy input and output of sweet sorghum grown as a bioenergy crop on coastal saline-alkali land. Energy 47: 166-173.
Robinson, P.H. 2001. Estimating the energy value of corn silage and other forages. Science 45: 1519-20.
Sefeedpari, P., Rafiee, S., and Pishgar Komleh, S.H. 2012. A source-wise and operation-wise energy use analysis for corn silage production, a case study of Tehran province, Iran. International Journal of Sustainable Built Environment 1: 158-166.
Sarmad, Z., Hejazi, E., and Bazargan, A. 2009. Research Methods in Behavioral Sciences. Agah Publication, Tehran, Iran 120 pp. (In Persian)
Soltani, A., Rajabi, M.H., Zeinali, E., and Soltani, E. 2009. Evaluation of environmental impact of crop production using LCA: wheat in Gorgan. Electronic Journal of Crop Production 3: 201-218. (In Persian with English Summary)
Soltani, A., Rajabi, M.H., Zeinali, E., and Soltani, E. 2013. Energy inputs and greenhouse gases emissions in wheat production in Gorgan, Iran. Energy 50: 54-61.
Suman, M., Singh, M., and Suman, B.L. 2006. Source of energy input and output for sustainable sorghum cultivation. Indian Journal of Crop Science 1(1-2): 135-137.
Tzilivakis, J., Warner, D.J., May, M., Lewis, K.A., and Jaggard, K. 2005. An assessment of the energy inputs and greenhouse gas emissions in sugar beet (Beta vulgaris) production in the UK. Agriculture System 85: 101-119.
Vitousek, P.M, Naylor, R, and Crews, T. 2009. Nutrient Imbalances in Agricultural Development. Science 324: 1519-1520.
Yousefi, M., Darijani, F., and Alipour Jahangiri, A. 2012. Comparing energy flow of greenhouse and open-field cucumber production systems in Iran. African Journal of Agricultural Research 7: 624-628.
Zahedi, M., and Eshghizadeh, H.R. 2014. Energy use efficiency and economical analysis in cotton production system in an arid region: A case study for Isfahan province, Iran. International Journal of Energy Economics and Policy 4: 43-52.
Zentner, R.P., Lafond, G.P., Derksen, D.A., Nagy, C.N., Wall, D.D., and May, W.E. 2004. Effects of tillage method and crop rotation on non-renewable energy use efficiency for a thin Black Chernozem in the Canadian Prairies. Soil and Tillage Research 77: 125-136.
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