الگوی مصرف انرژی و تجزیه و تحلیل حساسیت ورودی های انرژی و هزینه های ورودی برای تولید گلابی در ایران
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|26700||2013||6 صفحه PDF||سفارش دهید||4920 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Renewable Energy, Volume 51, March 2013, Pages 7–12
The purposes of this study were to determine energy use pattern and investigate the relationships between energy inputs and yield, cost inputs and income for pear production in the Tehran province of Iran. In this study, data were collected by administering a questionnaire in face-to-face interviews in the production year of 2009/2010. This article presents a comprehensive picture of the current status of energy consumption and some energy indices like energy ratio, energy productivity, specific energy, net energy and energy intensiveness. Results showed that the total energy input of 172,608.43 MJ ha−1 was required for pear production. Among input energy sources, electricity energy with share of 78% of total input energy had the highest share. The energy use efficiency and energy productivity were found as 0.51 and 0.27 kg MJ−1, respectively. To investigate the relationships between energy inputs and yield, cost inputs and income, Cobb–Douglas production function was selected as the best function. Sensitivity analysis of energy and cost inputs was carried out using the marginal physical productivity (MPP) technique. Economic analysis of pear production was carried out and total cost of pear production was obtained as 11,936.97 $ h−1. Also the benefit to cost ratio was calculated as 3.11.
Pears (Pyrus Communis L.) are qualified as a good source of vitamin C and copper in our food ranking system. Both of these nutrients can be thought of as antioxidant nutrients that help protect cells in the body from oxygen-related damage due to free radicals . In the world, pears are produced about 21.9 million tons from 1.7 million ha in 2009 . China had the first place in producing pears while Netherlands, Argentina, Belgium and Italy were important pears exporting countries in 2008. Iran with producing 115,812 tons of pears had the 20th place in pears production in the world in 2008 . The agriculture sector, like other sectors, has become increasingly dependent on energy resources such as electricity, fuels, natural gas and coke. This increase in energy use and its associated increase in capital intensive technology can be partially attributed to low-energy prices in relation to the resource for which it was being substituted . Modern crop production is characterized by the high input of fossil energy, which is consumed as “direct energy” (fuel and electricity used on the farm) and as “indirect energy” (energy spent beyond the farm for the manufacture of fertilizers, plant protection agents, machines, etc.) . The increased use of agricultural inputs in modern farming has resulted in an increase in the energy inputs for fertilizer and crop protection chemicals, higher yields have increased the energy output per unit area and per unit of input . A significant objective in agricultural production is to decrease costs and increase yield. In this respect, the energy budget is important. Energy budget is the numerical comparison of the relationship between input and output of a system or agricultural business in terms of energy units . In order to evaluate the sustainability of agriculture per se, the energetic efficiency must be considered and the major sources of energy wastes must be identified and assessed . Several studies have been conducted about energy analysis of agricultural crops production. Rajabi Hamedani et al.  analyzed energy use pattern of grape production in Iran. Mohammadi et al.  investigated energy inputs–yield relationship and cost analysis of kiwifruit production in Iran. They used Cobb–Douglas production function to estimate a relationship between energy inputs and yield. Esengun et al.  analyzed energy consumption of dry apricot production in Turkey. Hartirli et al.  studied energy inputs and crop yield relationship in greenhouse tomato production. Strapatsa et al.  investigated energy flow for integrated apple production in Greece. Ozkan et al.  examined energy use patterns and the relationship between energy inputs and yield for double crop (fall and summer) glasshouse tomato production in Turkey. In literature review there are many studies about agricultural products but there is no study about energy and cost analysis of pear production; so the objectives of this study were to determine the energy use pattern of pear production to investigate the efficiency of energy and to make a cost analysis of pear production. This study also generates the relationships between energy inputs and yield, cost inputs and income and analyzes sensitivity of inputs for pear production in Tehran province, Iran.
نتیجه گیری انگلیسی
The main objectives of this study were to investigate the relationships between energy inputs and the yield, cost inputs and income using Cobb–Douglas function and energy use patterns for pear production in Tehran province of Iran. From the present study following conclusions are drawn: 1. Total amount of energy consumption for pear production was 172,608.43 MJ ha−1. Electricity was the biggest energy consumer (77.86% of total energy usage) due to employing wrong irrigation method, while gasoline fuel was discovered as the least demanding energy input in all inputs (1.23%) due to lack of mechanization in the studied area. So, for decreasing energy consumption in irrigation it is recommended to change the irrigation method from flood irrigation to drip irrigation. Also, using horticultural machines can reduce labor energy and drudgery of farming. 2. Energy use efficiency and energy productivity were calculated as 0.51 and 0.27 kg MJ−1 respectively. 3. According to econometric model evaluated, human labor energy was the most significant input that influences on the production. 4. The benefit to cost ratio was estimated as 3.11 and among input costs human labor expense with share of 33% of total expense had the highest share. 5. Optimization is an effective tool to maximize productivity, which can reduce input energy use and production costs. So, the present study can be extended to distinguish efficient farmers from inefficient ones, determine wasteful uses of energy by the latter, and suggest optimum amounts of energy inputs for pear orchards.