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Journal of Sustainable Agriculture
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An Analysis of Energy Utilization for Sustainable
Wheat and Cotton Production in Southeastern
Anatolia Region of Turkey
M. Necat Oren & H. Huseyin Ozturk
To cite this article: M. Necat Oren & H. Huseyin Ozturk (2006) An Analysis of Energy Utilization for Sustainable Wheat and Cotton Production in Southeastern Anatolia Region of Turkey, Journal of Sustainable Agriculture, 29:1, 119-130
To link to this article: https://doi.org/10.1300/J064v29n01_09
Published online: 22 Sep 2008.
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for Sustainable Wheat and Cotton
Production in Southeastern
Anatolia Region of Turkey
M. Necat OrenH. Huseyin Ozturk
ABSTRACT. The aim of this study is to determine the energy input and output for wheat and cotton production in the Southeastern Anatolia re-gion of Turkey. The data used in this study were collected through a questionnaire by face-to-face interviews. In the study, the inputs in-cluded human labor, machinery, electricity, diesel fuel, oil, fertilizers and seeds which were taken into account in calculation of energy use for wheat and cotton production. Energy values were calculated by multi-plying the amounts of inputs and outputs by their energy equivalents with the use of related conversion factors. The output/input ratio was de-termined by dividing the output value by the input. The total energy used in various farm inputs were 17160 MJ/ha for wheat and 39538 MJ/ha for cotton production. The energy output/input ratio was found to be 2.21 for wheat and 2.38 for cotton production. The specific energy for wheat and cotton production was 7.18 MJ/kg and 10.52 MJ/kg, while the en-ergy productivity was found to be of the order of 0.14 kg/MJ and 0.095
M. Necat Oren is affiliated with Department of Agricultural Economics, Faculty of Agriculture, Çukurova University, 01330 Adana, Turkey (E-mail: mnoren@cu. edu.tr).
H. Huseyin Ozturk is affiliated with Department of Agricultural Machinery, Fac-ulty of Agriculture, Çukurova University, 01330 Adana, Turkey (E-mail: hhozturk@ cu.edu.tr).
Address correspondence to: M. Necat Oren at the above address. Journal of Sustainable Agriculture, Vol. 29(1) 2006
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kg/MJ, respectively. The results of the study reveal that improper pro-duction techniques applied at improper time, and irrational input use are the main causes of inefficiencies in energy use. Reduced tillage methods should be adopted in order to achieve considerable savings, particularly in mechanical energy.doi:10.1300/J064v29n01_09 [Article copies
avail-able for a fee from The Haworth Document Delivery Service: 1-800-HAWORTH. E-mail address: <docdelivery@haworthpress.com> Website: <http:// www.HaworthPress.com> © 2006 by The Haworth Press, Inc. All rights re-served.]
KEYWORDS. Cotton, energy analysis, Southeastern Anatolia, Turkey, wheat
INTRODUCTION
Energy consumption per unit area in agriculture is directly related with the development of technological level and production. The inputs such as fuel, electricity, machinery, seed, fertilizer and chemical take significant share of the energy supplies to the production system in modern agriculture. The use of intensive inputs in agriculture and ac-cess to plentiful fossil energy has provided an increase for standards of living and food production. However, some problems in agricultural production have been faced due to mainly high level dependency on fossil energy. In the recent years, energy use and associated greenhouse gas emissions and their potential impacts on the global climate change have been the worldwide concern. Improving the end-use energy effi-ciency is one of the most effective ways to reduce energy consumption in the industrial, commercial, transportation, utility, residential and ag-ricultural sectors and their associated pollutant emissions (Dyer and Desjardins, 2003).
Efficient use of the energy resources is vital in terms of increasing production, productivity, competitiveness of agriculture as well as sustainability to rural living (Singh et al., 2003). Energy auditing is one of the most common approaches to examine energy efficiency and envi-ronmental impact of the production system. It enables researchers to calculate input-output ratio, other relevant indicators and energy use pattern in an agricultural activity. Moreover, the energy audit provides sufficient data to establish functional forms to investigate the relation-ship between energy inputs and outputs. Estimating these functional forms is very useful in terms of determining elasticities of inputs on
yield and production (Ozkan et al., 2003). Energy use pattern and con-tribution of energy inputs vary depending on farming systems, crop sea-son and farming conditions. Considerable work has been conducted on the use of energy in agriculture with respect to efficient and economic use of energy for sustainable production. Energy input-output analysis is usually used to evaluate the efficiency and environmental impacts of production systems. This analysis is important to perform necessary im-provements that will lead to a more efficient and environment-friendly production system (Ozkan et al., 2003, 2004). Considerable researches have been performed on energy input and output in agricultural pro-duction (Yaldiz et al., 1990a,b, 1991, 1993; Singh et al., 1990, 1992, 1994, 1996, 1998a,b, 2000, 2003, 2004a,b; Jansen, 2001; Mrini et al., 2002; Ozkan et al., 2003; 2004; Dyer and Desjardins, 2003; Abay et al., 2004). Optimization of energy use in agriculture is reflected in two ways, that is, an increase in productivity at the existing level of energy inputs or conserving the energy without affecting the productivity (Singh et al., 2004a).
The share of the Southeastern Anatolia region in the total population of Turkey is almost 10% (SPO, 2005). The region has a surface area of 75358 km2, which corresponds to 9.7% of the total surface area of
Tur-key. A wide range of crops each requiring different climatic conditions are raised in this area. The region has 3.2 million hectares of land fit for crop culture. Forested areas make up 1.3 million hectares while 2.3 mil-lion hectares of land consists of pastures and ranges (SPO, 2005).
In the period 1990 through 2000, the rate of population growth in the region was 2.5% as annual average while it was 1.8% for the country (SPO, 2005). Field crop production contributes significant income, em-ployment and export opportunities in the research region. The South-eastern Anatolia Project (SAP) focuses on efficient utilization of these natural resources. For the first time in Turkey, the management, opera-tion and maintenance of new irrigaopera-tion systems have been directly transferred to irrigation districts, which are organizations formed by lo-cal farmers. In 1998, the region accounted for 41.6% of the total cotton output of Turkey (SPO, 2005). Favorable climatic conditions in the re-gion make it possible to reap two crops a year. In this context, research projects led by the SAP Administration focus on genetic improvement and development of advanced breeding techniques. Crop yields of cot-ton, wheat, barley, lentil and other grains have reportedly tripled in the Harran Plain as a result of irrigation from the Ataturk Dam. The Harran Plain is located at 36⬚43⬘-37⬚08⬘ N latitude and 38⬚57⬘-39⬚55⬘ E
longi-tude. The Harran Plain as the biggest plain of Southeastern Anatolia region has 152000 ha irrigable area. The plain is under the semiarid climate regime and it is dominated by clay-textured soils.
The region of SAP has a significant share in the total agricultural pro-duction in Turkey. The main crops grown in the SAP region are wheat, cotton, barley and lentil. These crops are grown in 75% of the total culti-vated field area in this region (SIS, 2004). For that reason, energy input and output in wheat and cotton production was examined in the present study. The main objective of this study is to evaluate the energy input and output for wheat and cotton production in the SAP region of Tur-key. Data for the production of wheat and cotton were collected from 132 farms by using a face-to-face questionnaire method. This study seeks to analyze the effect of indirect and direct energy on yield using functional form. In addition to these parameters, it was also aimed to calculate energy output/input, energy productivity and specific energy used in the field crop production.
MATERIALS AND METHODS The Basic Characteristics of Surveyed Farms
The study was conducted in Southeast Anatolia of Turkey. The field crop farmers were surveyed in Diyarbakir, Mardin and Sanlinurfa prov-inces of the SAP region. Data were collected from growers by using a face-to-face survey in the 2003-2004 production years. The data in-cluded energy inputs from different sources, data input to various farm operations and yield. Taking actual farm size as the variable, the total 132 farms were randomly selected by using stratified random sampling. The permissible error was defined to be 5% for 95% reliability (Yamane, 1967). n N S N D N S h h h h = ∑ + ∑ ( ) 2 2 2 (1)
where n is the required sample size, N is the number of holdings in target population, Nhis the number of population in h the stratified, Shis the variance of h the stratified, and D is the precision where (x X).
The total agricultural land of the investigated 132 farms is 2414 hect-ares. Although, farms over 50 hectares, which are only 6% of the total number of investigated farms, cultivate 28% of total land. The average
size of farms is 18.3 hectares, and 37.2% of farm land is under irriga-tion. This proportion is relatively high at small farm groups. In general, farm lands have been divided into many parcels. The average number of parcels is three. The 80.3% of the average operated land by farms is owned. Tenancy is more common at small farm groups.
Cultivation of Wheat and Cotton
In the survey area, generally moldboard plough and partly cultivator are used for first plowing for soil preparation for wheat cultivation. Then land roller is applied to the soil. Sowing is accomplished by cereal planters and centrifugal sowing machines are used for fertilization. Sprayers are used for weed control and in struggling with pests. Wheat is irrigated using underground water in case of inadequate precipitation. In general, electrical and diesel pumps are used for this purpose. Har-vesting is completely with combine harvesters and mostly trailers are used for transportation of the crop.
For cotton cultivation, first plowing is done with moldboard plough. Then soil is tilled by cultivator. Then land rollers are drawn and borders are formed for irrigation afterwards by using border preparation equip-ment. Planting is done completely with cotton sowing machine. Fertil-izer distributor is also used together with universal planter. Weed control is accomplished with tractor drawn hoes. This is followed by a few hand hoeing. Sprayers are used against pests. Irrigation water is supplied from canalettes where areas were put in operation by DSI (State Hydraulic Works). Underground water is used for irrigation in ar-eas not in operation at present or out of the project area. For this purpose electrical and diesel pumps are employed. Harvest is accomplished completely by hand picking.
Energy Input-Output Analysis
A proforma questionnaire was designed in order to collect the re-quired information related to the land possessed by the farmers and the utilization pattern, crop yield, operation time, fuel consumptions, elec-tricity consumption and seed, fertilizer and chemical inputs. The energy use values were determined by multiplying by the associated energy equivalents/coefficients. Energy equivalents of the input and output used in wheat and cotton production are given in Table 1. The data on energy use have been taken from a number of references, as indicated in the Table 1.
Machine energy input is calculated on the basis of its weight, with the coefficient appropriate for its class. The following formula was used to estimate the machine energy input (Yaldiz et al., 1990b, 1991):
ME W E
T EFC
= ×
× (2)
where ME is the machine energy input in MJ per hectare, W is the weight of the implement in kg, E is manufacturing energy of the agricul-tural machines or implements in kg, T is the economic life of the imple-ment in h, and EFC is the effective field capacity in ha per hour.
The oil consumption of the tractor was calculated depending on its power as follows (ASAE, 2003):
TABLE 1. Energy equivalents of different input and output used in field crop production
Input Energy equivalent
(MJ/unit)
Reference
Human labour (h) 2.3 Yaldiz et al., 1990a,b
Manufacturing energy (MJ/kg) Tractor 158.3 Doering, 1980 Combine 141.0 Agricultural implements 121.3 Fuel (L) Diesel 47.8 Cervinka, 1980 Oil (Lubricant) 42.5 Chemical fertilizers (kg)
Nitrogen 60.6 Singh et al., 2003;
Phosphorus 11.1 Ozkan et al., 2003
Potassium 6.7
Chemicals (kg) Yaldiz et al., 1990a,b,
Herbicides 238 Ozkan et al., 2003
Insecticides 199
Fungicides 92
Seed (kg)
Wheat 25 Yaldiz et al., 1990a,b
Cotton 25
Irrigation(m3) 0.63 Yaldiz et al.,
1990a,b;
Output (kg) Bukantis and Goodman, 1980;
Grain wheat 14.7 Ozkan et al., 2004
Straw 12.5
OC = 0.004⫻Pt (3) where OC is the oil consumption of the tractor in L per hour and Ptis the power of the tractor in kW.
In this study, besides exploring input-output energy and different forms of energy output/input ratio, specific energy and energy produc-tivity for the field crop production were also calculated using the fol-lowing equations suggested by Mittal and Dhawan (1988), Baishya and Sharma (1990) and Djevic and Dimitrijevic (2004).
Energy output/input ratio = Energy output/Energy input (4) Specific energy = Energy input/Yield output = MJ/kg (5) Energy productivity = Yield output/Energy input = kg/MJ. (6)
RESULTS AND DISCUSSION
The energy equivalents of the input and output in wheat and cotton production, and energy output/input ratios are illustrated in Table 2. The total energy consumption for cotton production was higher than that of wheat production. The total energy used in various farm inputs for wheat production was 17160 MJ/ha and 39538 MJ/ha, for cotton. The results revealed that 7.6 h of machinery power per hectare were con-sumed to produce wheat in the research area. Since the cultural prac-tices were not high in wheat cultivation, the human labor was only 38 MJ/ha. On the other hand, the human labor (1864 MJ/ha) was much higher for cotton production. The machine energy input was of the order of 491 MJ/ha in wheat production and 1027 MJ/ha in cotton production. Out of all the farm operations, seedbed preparation consumed the most energy followed by sowing and cultural practices and harvesting.
In wheat production, out of all the inputs, fertilizers have the biggest share in the total energy with a 43.8%. Fertilizer energy input is fol-lowed by the diesel-oil energy. According to Muhadar and Hignet (1982), energy used in the production of fertilizers accounts for about 40% of total energy used in agricultural production in developed coun-tries. Most of this energy was consumed in the production of nitrogen, phosphorus and potassium fertilizers. In this study, nitrogen, phospho-rus and potassium were considered as chemical fertilizer inputs. Results show that nitrogen is the most important energy source with a value of 6715 MJ/ha, whereas phosphorus accounted for 801 MJ/ha. The die-sel-oil energy was mainly used for operating tractor for performing the
TABLE 2. The energy output/input relationship for wheat and cotton production
Input Quantity per Hectare Total Energy
Equiv-alent (MJ/ha)
Percentage of Total Energy
Input (%)
Wheat Cotton Wheat Cotton Wheat Cotton
Human labour (h) 16.6 810.3 38 1864
Seedbed preparation 4.8 10.7 11 25 0.22 4.71
Sowing and cultural practices
10.4 227.1 24 522
Harvesting 1.4 572.5 3 1317
Machinery (h) 7.6 20.1 491 1027
Seedbed preparation 4.8 10.7 209 482 2.86 2.60
Sowing and cultural practices
2.0 9.4 145 545
Harvesting 0.8 – 137 –
Diesel-oil (L) 134 337.2 6815 16304
Seedbed preparation 80.52 179.5 4228 8679 39.72 41.24 Sowing and cultural
practices 33.55 157.7 1621 7625 Harvesting 20.0 – 966 – Chemical fertilizer (kg) 183.0 291.1 7516 13691 Nitrogen 110.8 211.3 6715 12805 43.80 34.63 Phosphorus 72.2 79.8 80 886 Chemicals (kg) 1 1.9 161 385 Insecticides 0.1 0.6 20 119 0.94 0.97 Herbicides 0.4 1 95 238 Fungicides 0.5 0.3 46 28 Irrigation (m3) 1587.3 7936.5 1000 5000 5.83 12.65 Seed (kg) 227.7 50.7 1139 1268 6.63 3.21
Total Energy Input (MJ/ha) – 17160 39538 100.00 100 Output (kg) 2612.1 3757.8 37906 93945 Grain 2388.5 35111 Straw 223.6 2795 Output/input ratio 2.21 2.38 Specific energy (MJ/kg) 7.18 10.52 Energy productivity (kg/MJ) 0.14 0.095
various farm operations. The results showed that the average yield in wheat production was 2612 kg/ha. Therefore, in wheat production the energy output/input ratio was 2.2 MJ/kg, specific energy 7.2 MJ/kg and energy productivity 0.14 kg/MJ. Canakci et al. (2004) determined that the energy output/input ratio and specific energy for cultivating wheat were 2.8 and 5.24 MJ/kg in Antalya region of Turkey. Wheat is an en-ergy frugal crop, compared with most other food crops. The enen-ergy in-puts for wheat production in various regions of the U.S. were calculated by Krummel and Chick of Cornell University. They found that the en-ergy output/input ratios were 0.43 MJ/kg for wheat production in Texas, 1.66 in New Mexico, 2.21 in North Dakota, 3.61 in Ohio and 5.75 in Nebraska (Briggle, 1980).
The total energy used in various farm operations for cotton pro-duction was 39538 MJ/ha. The human power for cotton propro-duction was 1864 MJ/ha. The majority of the human power is devoted to har-vesting the cotton. In cotton production, the diesel-oil energy input was the highest in the total energy consumption with the value of 16304 MJ/ha followed by fertilizers (13691 MJ/ha). The percentages of total energy were 12.6% for irrigation, 4.7% for human labor, 2.6% for machinery and 34.6% for chemical fertilizers. Singh et al. (2000) found that for the cotton crop, seedbed preparation, irrigation and weeding consumed about 70% of the total energy input.
The results showed that average yield in seed cotton was 3758 kg/ha. In the case of cotton production the energy output/input ratio for cotton was 2.4 MJ/kg, specific energy was 10.5 MJ/kg, and energy productiv-ity was 0.095 kg/MJ. Canakci et al. (2004) determined that the energy output/input ratio and specific energy for cultivating cotton were 4.8 and 11.24 MJ/kg in Antalya region of Turkey.
CONCLUSIONS
Considerable savings could be obtained in machinery energy inputs by adopting a reduced tillage methods. The estimated energy output/in-put ratio for cultivation of wheat and cotton suggests that cotton is more remunerating to the farmers in SAP region. The low level of energy out-put/input ratio indicated that all the farmers were not fully aware of the right production techniques or did not apply them at the proper time in the right quantity. Cotton production was the most energy intensive among the two field crops investigated. The diesel-oil and the level of fertilizer input particularly nitrogen, were two of the most significant
determinants of the total energy input for field crop production. These results indicate that Turkish field crops heavily depend on fossil fuels. Therefore, policies should emphasize development of new technologies and alternative energy resources aiming at efficient use of energy. The results also imply that Turkish field crop production might be consid-ered as sensitive to changes in prices and availability of fossil fuels due to mainly its significant share in total consumed energy in field crop production. The results of this study can be used by policy makers and other relevant agencies for recommendations to farmers in order to use energy more efficiently. Proper management of resources and their application at the right time can improve efficiency in the use of farm inputs.
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