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Analysis of energy input and output for honey production in Iran (2012–2013)
Renewable and Sustainable Energy Reviews 59 (2016) 952–957
Contents lists available at ScienceDirect
Renewable and Sustainable Energy Reviews journal homepage: www.elsevier.com/locate/rser
Analysis of energy input and output for honey production in Iran (2012–2013) Omid Omidi-Arjenaki n, Rahim Ebrahimi, Davoud Ghanbarian Department of Mechanical of Biosystem, Shahrekord University, Iran
art ic l e i nf o
a b s t r a c t
Article history: Received 20 October 2014 Received in revised form 11 January 2016 Accepted 13 January 2016
The objectives of this study were to determine the energy consumption and evaluation of inputs for honey production in Shahrekord city in the Chaharmahal Va Bakhtiary province, Iran to investigate the efficiency of energy consumption and to make an economic analysis of honey production. Data used in this study were obtained from 80 beekeepers using a face to face questionnaire method. The sample bee keepings were selected through a stratified random sampling technique. The following results were obtained at the end of the study: with 54.43% the input of sugar is the highest within the energy equivalences of input used in honey production. This is followed by electricity and transportation with 14.02% and 13.84%, respectively. The total energy inputs, total energy outputs, input–output energy ratio and productivities were 28941.51 MJ hive 1, 15264 MJ hive 1, 0.54 and 0.04, respectively. The results indicated that all of the inputs affected the yield significantly, except electricity. The fuel (2815.5 MJ hive 1) and sugar (15292.2 MJ hive 1) were affected significantly with 0.547 and 0.459 coefficients, respectively. The input–output energy ratio shows that the inputs used in the production of honey are not used efficiently. Extension activities are needed to improve the efficiency of energy consumption in honey production and to employ environmentally friendly agricultural management practices and production methods. & 2016 Elsevier Ltd. All rights reserved.
Keywords: Energy efficiency Input and output energy Honey Beekeeping Sugar
Contents 1. Introduction . . . . . . . . . 2. Materials and methods 3. Results . . . . . . . . . . . . . 4. Discussion . . . . . . . . . . 5. Conclusion . . . . . . . . . . References . . . . . . . . . . . . . .
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1. Introduction Cave paintings depicting honey harvesting dating from about 7000 B.C. have been discovered in Spain [8]. Commercial production of honey with 80% [25] sugar content is relatively efficient for human consumption in comparison with sugar cane or sugar beet production [28]. From that time, the beekeeping was interested for food production for human and the man looking for n
Corresponding author: Tel.: þ 98 9131836404 E-mail addresses: [email protected], [email protected] (O. Omidi-Arjenaki). http://dx.doi.org/10.1016/j.rser.2016.01.060 1364-0321/& 2016 Elsevier Ltd. All rights reserved.
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knowledge of taking maximum advantage from it and its products. Honey (with 3040 kcal/kg energy value) is a useful source of highcarbohydrate food, and usually contains a rich diversity of minor constituents (minerals, proteins, vitamins and others), adding nutritional variety to human diets. In many countries, honey is regarded more as a medicine or special tonic, rather than as an every-day food. Honey does have medicinal properties that are increasingly acknowledged by modern medicine. In Iran, beekeeping and honey use and production has a long history. By means of the development of beekeeping in Europe and the import of modern hives and hybrid female queens (1956), Iranian enthusiasts became interested in the establishment of large
O. Omidi-Arjenaki et al. / Renewable and Sustainable Energy Reviews 59 (2016) 952–957
beekeeping units. Iran ranked fourth in number of colonies of honey, with about 5,600,000 colonies, and eighth in honey production in the world. Annually, in Iran about 71,000 and 250 t of honey are harvested and per capita consumption of honey is about 610 g per person. In Shahrekord about 116,000 and 104 kg of honey from 25,000 colonies are harvested each year [Agricultural Organization of Province]. There are 19884 ha fields of forage plants such as alfalfa, sainfoin and clover in the region, caused that the area is suitable for beekeeping. The colonies in summer countryside are deployed in Astragalus fields and in spring and flowering time of trees and plants, would be established in farms, orchards and gardens in the vicinity of the Zayanderood river. Beekeepers in autumn and winter migrate to neighboring tropical provinces. Honey harvest begins in early August. Keeping bees is in wooden hives. All processes during the beekeepers, as is typical and traditional and harvesting honey are carried out by traditional means (ex. smoke generators, electric or manual extractor). In the past decades, the commercial production of honey for human consumption is relatively efficient compared with the production of cane and beet sugar [29]. honey production requires large fossil energy inputs to provide the necessary equipment and supplies. The cane and beet sugar require about 2–3 times more energy to produce than honey [29]. The annually input energy for a commercial beekeeping in USA with 1000 colonies was measured. In that study, the total energy spent in production was 450.77 GJ and in maintenance and packaging was 64.4 GJ. The output energy for 45 t of honey was 572.4 GJ [28]. Worldwide, energy analysis studies have been conducted by researchers to determine the energy efficiency spent in the production process [10,14,16–24,30]. For this purpose, they have determined the contribution of each energy input, energy productivity, the specific energy, output–input energy ratio, net energy gain and the contribution of different energy forms, including direct, indirect, renewable and non-renewable. The efficient use of energy is one of the principal requirements of sustainable agriculture. Energy use in agriculture has been increasing in response to the increase of population, limited supply of arable land, and a desire for higher standards of living. The continuous demand for the increase of food production resulted in intensive use of chemical fertilizers, pesticides, agricultural machinery, and other natural resources. However, intensive use of energy causes problems threatening public health and environment. Efficient use of energy in agriculture will minimize environmental problems, prevent destruction of natural resources, and promote sustainable agriculture as an economical production system. In this study the input and output energy of honey production in Shahrekord were calculated and energy indexes, the most commonly used inputs and their effects coefficients in yield were analyzed.
2. Materials and methods Data were collected from 80 beekeepers in Shahrekord, the capital of the Chaharmahal Va Bakhtiary province, Iran, by using a face-to-face questionnaire performed during winter 2012 and summer 2013 because of its one of major contributions to honey production in Iran by 6.1% of national production. In addition some data were obtained from the province's Beekeepers Association. Beekeepers that are producing honey were recorded, the total amounts of sugar and numbers of colonies (300–2000) were determined. Random sampling of beekeeping was done within the whole population and the size of each sample was determined
953
using Eq. (1) derived from the Neyman method [31,22]: P N h Sh n¼ 2 2 P N h S2h N D þ
ð1Þ
where n is the required sample size; N is the number of holdings in target population; Nh is the number of the population in the h stratification; Sh is the standard deviation in the h stratification, Sh2 is the variance of h stratification; D2 ¼ d2/z2 where d is the precision (x X) and z is the reliability coefficient (z¼ 1.96 which represents the 95% reliability). For the calculation of sample size, criteria of 5% deviation from population mean and 95% confidence level were used. The sampling size was considered as n¼ 80. The samples were selected randomly and data were collected in MS Excel. In this region, the honey production inputs are human labor, machinery, diesel fuel, drug, sugar and electricity. The output was honey. The quantity of the various inputs used and the production outputs were calculated per hives, based on the information obtained from the questionnaires. The energy equivalent of inputs and output are showed in Table 1 and the most commonly used operations and practices in honey production in the studied region are listed in Table 2. In Asia there is a greater variety of honey bees, three representative species all being widely distributed: Apis cerana, Apis dorsata and Apis florea. Apis cerana, the native hive bee of Asia, is very similar to Apis mellifera but slightly smaller [7]. In studied region, in addition to cerana and mellifera, ligustica and carnica subspecies are also kept. By using the equivalent energy of inputs and outputs, input and output energies of honey production were calculated. Based on the calculated energy of inputs and produced honey, the energy ratio (energy efficiency), specific energy and energy productivity were calculated [2,15]: Output input ratio ¼
Energy output ; Energy input
ð2Þ
Table 1 The energy equivalent of inputs. Input/output Inputs: Labor Fuel Electricity Track Drug Sugar Output: Honey
Unit
Energy equivalent (MJ unit-1)
Reference
h l kW h km ton kg kg
1.96 56.31 11.93 10.15 13.64 15.4
[33, 23, 26, 5, 10] [33, 12, 4, 5, 1] [26, 20, 10, 21] [9] [19] [6]
kg
12.72
[28, 3]
Table 2 Practices and operations for honey production. Practice/operation
Description
Bee subspecies Location of the hives establishment Transports type Cooling equipment The number of bee colonies Drug Spraying device Extractor type Hive types Working temperature (Celsius) Distance between hives (Centimeters) Time to replace the queen Food in winter
ligustica, carnica, mellifera, cerana Alfalfa and astragalus fields (in winter) and orchards (in summer) Track Water Cooler, Fan 300–2000 Pesticides, Coumaphos Traditional pump spray Electric and manual Wooden 8–34 40–150 In spring or in disability Honey syrup, Sugar syrup
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Energy productivity ¼ Specific energy ¼
Honey output ; Energy input
ð3Þ
Energy input ; Honey output
ð4Þ
The calculated data correspond to one year. The energy of fuel and electricity were obtained by multiplying the energy input content (fuel: MJ l 1, electricity: MJ kW h 1) by the consumed input units (fuel: l, electricity: kW h). The total energy of fuel and electricity were obtained. The daily hour of activity of labors was dependent on beekeeping conditions and terms of the beekeepers. For each of the analysis of inputs and produced honey correlation, the Stepwise linear regression model and the cobb-Douglas model were used [18,11,27]. Thus, important inputs were identified. The input energy was divided into direct, indirect, renewable, and nonrenewable energies [13]. Indirect energy included energy spent in transportation (through tracks) while direct energy covered human labor and fuel used in the honey production process. Nonrenewable energy includes fuel, sugar, electricity and drug and renewable energy consists of human labor.
Table 5 The mean of energy indices. Index
Value
Input energy Output energy Performance Energy productivity Energy efficiency
361.77 MJ/hive 190.8 MJ/hive 15 kg/hive 0.04 kg/MJ 0.54
3. Results The total energy of fuel and electricity were 3318.066 GJ and 4637.525 GJ, respectively. The mean value of daily work hour and annually workday of labor were 7.16 h and 320 day (max: 12 h, min: 3 h daily). The total energy of labor input was 2259.174 GJ. The consumption of the maximum and minimum energy consumers are illustrated in Table 3. Also, the total input and output energy are illustrated in Table 4. The indices of energy were calculated and their means are listed in Table 5. According to Table 5, the energy performance was calculated as 0.54. This value indicates that each kilogram of honey produced in Shahrekord needs a considerable amount of energy. To produce each kilogram of honey, 24.22 MJ of energy is used, on average. Frequencies of Table 3 The maximum and minimum energy consumers. Inputs/outputs
Inputs: Labor Fuel Electricity Track Drug Sugar Total
Total energy (MJ/hive) Beekeeping no. 32 (Minimum use)
Beekeeping no. 76 (Maximum use)
25.66 35.19 107.04 48.52 0.012 154 370.41
37.91 35.19 31.07 48.52 0.05 215.6 368.29
Table 4 Total input and output energy. Inputs/outputs Inputs: Labor Fuel Electricity Track Drug Sugar Output Honey
Total energy (GJ/hive)
2.24 2.82 4.71 3.88 0.003 15.29 15.26
Fig. 1. Frequency of specific energy value in beekeeping units.
specific energy values are showed in Fig. 1. Also, in Table 6, other values of energy are very low or poor. So the mean of total output energy and total net energy are 225058.14 MJ and 188238.56 MJ, respectively. However, at this point it should not be forgotten that honey production is not energy positive; more energy is needed in the production than the one the product has [32]. The frequencies of productivity of energy values are showed in Fig. 2. The fluctuations in specific energy and productivity of energy in beekeeping units indicate that there was no proper management of the production. In the initial analysis of the data, the reason for rejecting the claim that input values are normally distributed (Kolmogorov–Smirnov) didn't exist (p 40.01). The visual information in Figs. 1 and 2 were corroborated the lack of normal distribution. The annual total input and output energy in producers were calculated as 28.942 MJ hive 1 and 15.264 MJ hive 1, respectively. The results of the Analysis of Variance (ANOVA) indicated that the mean of energy efficiency in producers of honey was not significantly different within three groups (fewer than 1100 hives, 1100–1500 and more than 1500 hives) (p ¼0.239). Also, the analysis indicated that the sugar was the largest amount of input energy. On average, 12.41 kg of sugar per hive were used (Fig. 3 – the drug was ignored.). This amount of sugar contained 114.191 MJ of energy. The sugar, with a ratio of 2:1 or 1:1 (depending on the season) was mixed with water, to make sugar syrup for feed the bees. The total of sugar energy in all producers was 17995.67 GJ. More sugar consumption is needed in spring for the honey bees due to population increasing. Even if the population was low before winter, the concentrate of sugar syrup is added. A beekeeper uses 12 kg of sugar per hive (24 kg of sugar syrup with 1:1 ratio) usually annually. The results of input energy, output energy and energy indices are indicated in Table 6. The third level of sugar consumption has the maximum energy productivity and efficiency. In this level, 1.165 kg of honey was produced for each Mega
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Table 6 The results of input energy, output energy and energy indices. Sugar consumption (kg)
Producer number
Input energy (MJ/hive)
Output energy (MJ/hive)
Specific energy (MJ/kg)
Productivity (kg/MJ)
Efficiency (mean)
X o 12 12o xo 14 144 x
26 27 27
9388.412 9853.926 9699.167
4922.64 5088.00 5253.36
632.17 667.57 637.85
1.081 1.106 1.165
0.53 0.52 0.55
joule of energy used. For investigating the effect of energy inputs on output and conduct an analysis with the Cobb–Douglas production function, the coefficient of determination was calculated, being 0.977 (Table 7). The results showed that the fuel and sugar have the most important energy input with share of 51.0% and 46.1% of total energy (Fig. 4, left). These results indicate that, by adding 1% of sugar or fuel consumption, the honey production increases 0.52% or 0.48%, respectively (Fig. 4. right). The Cobb– Douglas function was obtained: LnðY i Þ ¼ 1:466 þ 0:523LnðX 1 Þ 0:064LnðX 2 Þ þ 0:005LnðX 3 Þ þ 0:482LnðX 4 Þ
Fig. 2. Frequency of productivity of energy in beekeeping units.
ð5Þ
where Y i denotes the yield level of the i-th beekeeper and X 1 , X 2 , X 3 and X 4 are energy of fuel, electricity, labor and sugar, respectively. In the Stepwise model, each input was analyzed and if it hasn't a significant effect in the regression, it was removed. In this case the coefficient of determination was calculated, being 0.976. The fuel and sugar were important inputs with 0.574 and 0.459 importance coefficients (Table 8). According to the Beta coefficient column, the regression equation was obtained: LnðY i Þ ¼ 0:842 þ 0:547LnðX 1 Þ 0:459LnðX 4 Þ
ð6Þ
4. Discussion According to the results, most of the honey manufacturers in Shahrekord were not explainable and affordable, according to the rate of use and energy efficiency. However, because honey production mainly occurs in normal weather conditions, there is no solution to improve sufficiently the production conditions in terms of weather problems. But in other part's production, the honey quality can be raised. Some of the main reasons for such a situation for the producers of honey are as follows: 1. Low cost of energy inputs. 2. Disorder and influenced activity of bees by the pollution, dust, and also intense radio waves like cell phone and compel beekeepers to settle and travel to distant places. 3. The indiscriminate use the sugar and fuel consumption. 4. Drought and the early summer heat. 5. Mismanagement of the energy consumption in other inputs.
Fig. 3. Inputs energy.
Table 7 The results of Cobb–Douglas model. Independent variables
Regression ratio
Standard ratio
t
(Constant) Fuel Sugar Electricity Labor
1.466 0.523 0.482 0.065 0.007
0.510 0.461 0.028 0.002
3.460n 7.776n 7.393n 1.824ns 0.436ns
n
ns
Significant in 1% level. Not significant.
The results showed that sugar was the largest input energy within the primary inputs in honey production. Specific energy values, energy productivity and the mean value of energy efficiency in honey manufacturers in this city, was 24.22 MJ kg 1, 0.04 kg MJ 1 and 54%, respectively. Within the relationship between energy inputs and efficiency, fuel consumption with 51.0% and sugar with 46.1% were the most important factors. Sugar consumption in the over 14 kg hive 1 group showed that for each MJ of energy, 1.165 kg of honey is produced. Correct management in the honey production and achieving goals in beekeeping, needs monitoring, and typically, manufacturers can be monitored by the beekeepers associations and relevant helping institutions. Considering the large negative value of net energy in honey production the important issue was that contrary to the popular belief in
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Fig. 4. Cobb–Douglas model, (right) honey production variation by the sugar and fuel increasing (left) diagram of the important factors affecting the performance. Table 8 Results in Stepwise model. Independent variables
Regression ratio
Standard ratio
t
(Constant) Fuel Sugar
0.842 0.547 0.459
0.535 0.463
3.777n 8.231n 7.124n
n
Significant in 1% level.
Iran, honey isn't the only output in bee-keepings. In developed countries the last revenues of beekeepers is due to honey, and their main income is obtained from the other bee products such as Royal Jelly, Propolis, Pollen and Bee Venom. In some countries pollinating bees in the farmers gardens are the main source of income and honey income will be mostly spent in production costs. Meanwhile, in Iran the only option for beekeepers is producing the honey. Problems of the hives and the transfer of beekeeper equipment between areas in different seasons, the lack of accommodation for bees and beekeepers, the lack of using bee culture in farm fields the idea of most gardeners that their product is damaged by bee activity, cell phone radiation and pollution, force the beekeepers further away from the cities, and apart from gardens and farms. However, research has showed that the bee activity can raise the tonnage of agricultural products in fruit gardens because of the pollination. On the other hand, farmers spraying without noticing the adjacent beekeepers cause the death of bees and the declining in the production of honey and other products. The phenomenon of dust has not been ineffective on the performance of beekeepers and it's became a problem in honey production in recent years in Iran. Another issue regarding the monitoring was the lack of study in some beekeepers, and the unfamiliarity with technical issues and beekeeping, like switching the queen in the exact time, knowledge about the true value of the properties of bee products and the lack of communication with universities and research centers.
5. Conclusion The following conclusions were drawn from the study: 1. The total energy consumption for honey production was 28.942 MJ hive 1. Sugar energy was found to be the biggest energy consumer among all energy sources. Adequate and proper use of sugar can help to reduce the sugar energy consumed in honey production. 2. Energy use efficiency for honey productions in Shahrekord were calculated as 0.54, which shows an inefficient use of energy in beekeeping. The energy ratio can be increased by decreasing the energy input consumption.
3. The impact of human labor energy input for honey production was significantly positive on yield. 4. Optimization is an effective tool to maximize the amount of productivity which can reduce the input energy use and production costs. So, the present study can be extended to specify efficient beekeepers from inefficient ones, determine wasteful uses of energy inputs by inefficient farmers and suggest the optimum amounts of each inputs to be utilized by each inefficient beekeeper from the input energy sources. 5. Mechanizing the beekeeper and entering advanced equipment production of bee products such as wax harvesting devices, venom harvesters and devices that use less energy inputs while have higher output yields, reforming the old hives with standard and modern hives, and replacing trim and young queens with old and native queens, together with the use of renewable energy sources such as solar energy or wind energy can raise the operation, energy efficiency and productivity of honey production.
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Contents lists available at ScienceDirect
Renewable and Sustainable Energy Reviews journal homepage: www.elsevier.com/locate/rser
Analysis of energy input and output for honey production in Iran (2012–2013) Omid Omidi-Arjenaki n, Rahim Ebrahimi, Davoud Ghanbarian Department of Mechanical of Biosystem, Shahrekord University, Iran
art ic l e i nf o
a b s t r a c t
Article history: Received 20 October 2014 Received in revised form 11 January 2016 Accepted 13 January 2016
The objectives of this study were to determine the energy consumption and evaluation of inputs for honey production in Shahrekord city in the Chaharmahal Va Bakhtiary province, Iran to investigate the efficiency of energy consumption and to make an economic analysis of honey production. Data used in this study were obtained from 80 beekeepers using a face to face questionnaire method. The sample bee keepings were selected through a stratified random sampling technique. The following results were obtained at the end of the study: with 54.43% the input of sugar is the highest within the energy equivalences of input used in honey production. This is followed by electricity and transportation with 14.02% and 13.84%, respectively. The total energy inputs, total energy outputs, input–output energy ratio and productivities were 28941.51 MJ hive 1, 15264 MJ hive 1, 0.54 and 0.04, respectively. The results indicated that all of the inputs affected the yield significantly, except electricity. The fuel (2815.5 MJ hive 1) and sugar (15292.2 MJ hive 1) were affected significantly with 0.547 and 0.459 coefficients, respectively. The input–output energy ratio shows that the inputs used in the production of honey are not used efficiently. Extension activities are needed to improve the efficiency of energy consumption in honey production and to employ environmentally friendly agricultural management practices and production methods. & 2016 Elsevier Ltd. All rights reserved.
Keywords: Energy efficiency Input and output energy Honey Beekeeping Sugar
Contents 1. Introduction . . . . . . . . . 2. Materials and methods 3. Results . . . . . . . . . . . . . 4. Discussion . . . . . . . . . . 5. Conclusion . . . . . . . . . . References . . . . . . . . . . . . . .
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1. Introduction Cave paintings depicting honey harvesting dating from about 7000 B.C. have been discovered in Spain [8]. Commercial production of honey with 80% [25] sugar content is relatively efficient for human consumption in comparison with sugar cane or sugar beet production [28]. From that time, the beekeeping was interested for food production for human and the man looking for n
Corresponding author: Tel.: þ 98 9131836404 E-mail addresses: [email protected], [email protected] (O. Omidi-Arjenaki). http://dx.doi.org/10.1016/j.rser.2016.01.060 1364-0321/& 2016 Elsevier Ltd. All rights reserved.
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knowledge of taking maximum advantage from it and its products. Honey (with 3040 kcal/kg energy value) is a useful source of highcarbohydrate food, and usually contains a rich diversity of minor constituents (minerals, proteins, vitamins and others), adding nutritional variety to human diets. In many countries, honey is regarded more as a medicine or special tonic, rather than as an every-day food. Honey does have medicinal properties that are increasingly acknowledged by modern medicine. In Iran, beekeeping and honey use and production has a long history. By means of the development of beekeeping in Europe and the import of modern hives and hybrid female queens (1956), Iranian enthusiasts became interested in the establishment of large
O. Omidi-Arjenaki et al. / Renewable and Sustainable Energy Reviews 59 (2016) 952–957
beekeeping units. Iran ranked fourth in number of colonies of honey, with about 5,600,000 colonies, and eighth in honey production in the world. Annually, in Iran about 71,000 and 250 t of honey are harvested and per capita consumption of honey is about 610 g per person. In Shahrekord about 116,000 and 104 kg of honey from 25,000 colonies are harvested each year [Agricultural Organization of Province]. There are 19884 ha fields of forage plants such as alfalfa, sainfoin and clover in the region, caused that the area is suitable for beekeeping. The colonies in summer countryside are deployed in Astragalus fields and in spring and flowering time of trees and plants, would be established in farms, orchards and gardens in the vicinity of the Zayanderood river. Beekeepers in autumn and winter migrate to neighboring tropical provinces. Honey harvest begins in early August. Keeping bees is in wooden hives. All processes during the beekeepers, as is typical and traditional and harvesting honey are carried out by traditional means (ex. smoke generators, electric or manual extractor). In the past decades, the commercial production of honey for human consumption is relatively efficient compared with the production of cane and beet sugar [29]. honey production requires large fossil energy inputs to provide the necessary equipment and supplies. The cane and beet sugar require about 2–3 times more energy to produce than honey [29]. The annually input energy for a commercial beekeeping in USA with 1000 colonies was measured. In that study, the total energy spent in production was 450.77 GJ and in maintenance and packaging was 64.4 GJ. The output energy for 45 t of honey was 572.4 GJ [28]. Worldwide, energy analysis studies have been conducted by researchers to determine the energy efficiency spent in the production process [10,14,16–24,30]. For this purpose, they have determined the contribution of each energy input, energy productivity, the specific energy, output–input energy ratio, net energy gain and the contribution of different energy forms, including direct, indirect, renewable and non-renewable. The efficient use of energy is one of the principal requirements of sustainable agriculture. Energy use in agriculture has been increasing in response to the increase of population, limited supply of arable land, and a desire for higher standards of living. The continuous demand for the increase of food production resulted in intensive use of chemical fertilizers, pesticides, agricultural machinery, and other natural resources. However, intensive use of energy causes problems threatening public health and environment. Efficient use of energy in agriculture will minimize environmental problems, prevent destruction of natural resources, and promote sustainable agriculture as an economical production system. In this study the input and output energy of honey production in Shahrekord were calculated and energy indexes, the most commonly used inputs and their effects coefficients in yield were analyzed.
2. Materials and methods Data were collected from 80 beekeepers in Shahrekord, the capital of the Chaharmahal Va Bakhtiary province, Iran, by using a face-to-face questionnaire performed during winter 2012 and summer 2013 because of its one of major contributions to honey production in Iran by 6.1% of national production. In addition some data were obtained from the province's Beekeepers Association. Beekeepers that are producing honey were recorded, the total amounts of sugar and numbers of colonies (300–2000) were determined. Random sampling of beekeeping was done within the whole population and the size of each sample was determined
953
using Eq. (1) derived from the Neyman method [31,22]: P N h Sh n¼ 2 2 P N h S2h N D þ
ð1Þ
where n is the required sample size; N is the number of holdings in target population; Nh is the number of the population in the h stratification; Sh is the standard deviation in the h stratification, Sh2 is the variance of h stratification; D2 ¼ d2/z2 where d is the precision (x X) and z is the reliability coefficient (z¼ 1.96 which represents the 95% reliability). For the calculation of sample size, criteria of 5% deviation from population mean and 95% confidence level were used. The sampling size was considered as n¼ 80. The samples were selected randomly and data were collected in MS Excel. In this region, the honey production inputs are human labor, machinery, diesel fuel, drug, sugar and electricity. The output was honey. The quantity of the various inputs used and the production outputs were calculated per hives, based on the information obtained from the questionnaires. The energy equivalent of inputs and output are showed in Table 1 and the most commonly used operations and practices in honey production in the studied region are listed in Table 2. In Asia there is a greater variety of honey bees, three representative species all being widely distributed: Apis cerana, Apis dorsata and Apis florea. Apis cerana, the native hive bee of Asia, is very similar to Apis mellifera but slightly smaller [7]. In studied region, in addition to cerana and mellifera, ligustica and carnica subspecies are also kept. By using the equivalent energy of inputs and outputs, input and output energies of honey production were calculated. Based on the calculated energy of inputs and produced honey, the energy ratio (energy efficiency), specific energy and energy productivity were calculated [2,15]: Output input ratio ¼
Energy output ; Energy input
ð2Þ
Table 1 The energy equivalent of inputs. Input/output Inputs: Labor Fuel Electricity Track Drug Sugar Output: Honey
Unit
Energy equivalent (MJ unit-1)
Reference
h l kW h km ton kg kg
1.96 56.31 11.93 10.15 13.64 15.4
[33, 23, 26, 5, 10] [33, 12, 4, 5, 1] [26, 20, 10, 21] [9] [19] [6]
kg
12.72
[28, 3]
Table 2 Practices and operations for honey production. Practice/operation
Description
Bee subspecies Location of the hives establishment Transports type Cooling equipment The number of bee colonies Drug Spraying device Extractor type Hive types Working temperature (Celsius) Distance between hives (Centimeters) Time to replace the queen Food in winter
ligustica, carnica, mellifera, cerana Alfalfa and astragalus fields (in winter) and orchards (in summer) Track Water Cooler, Fan 300–2000 Pesticides, Coumaphos Traditional pump spray Electric and manual Wooden 8–34 40–150 In spring or in disability Honey syrup, Sugar syrup
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Energy productivity ¼ Specific energy ¼
Honey output ; Energy input
ð3Þ
Energy input ; Honey output
ð4Þ
The calculated data correspond to one year. The energy of fuel and electricity were obtained by multiplying the energy input content (fuel: MJ l 1, electricity: MJ kW h 1) by the consumed input units (fuel: l, electricity: kW h). The total energy of fuel and electricity were obtained. The daily hour of activity of labors was dependent on beekeeping conditions and terms of the beekeepers. For each of the analysis of inputs and produced honey correlation, the Stepwise linear regression model and the cobb-Douglas model were used [18,11,27]. Thus, important inputs were identified. The input energy was divided into direct, indirect, renewable, and nonrenewable energies [13]. Indirect energy included energy spent in transportation (through tracks) while direct energy covered human labor and fuel used in the honey production process. Nonrenewable energy includes fuel, sugar, electricity and drug and renewable energy consists of human labor.
Table 5 The mean of energy indices. Index
Value
Input energy Output energy Performance Energy productivity Energy efficiency
361.77 MJ/hive 190.8 MJ/hive 15 kg/hive 0.04 kg/MJ 0.54
3. Results The total energy of fuel and electricity were 3318.066 GJ and 4637.525 GJ, respectively. The mean value of daily work hour and annually workday of labor were 7.16 h and 320 day (max: 12 h, min: 3 h daily). The total energy of labor input was 2259.174 GJ. The consumption of the maximum and minimum energy consumers are illustrated in Table 3. Also, the total input and output energy are illustrated in Table 4. The indices of energy were calculated and their means are listed in Table 5. According to Table 5, the energy performance was calculated as 0.54. This value indicates that each kilogram of honey produced in Shahrekord needs a considerable amount of energy. To produce each kilogram of honey, 24.22 MJ of energy is used, on average. Frequencies of Table 3 The maximum and minimum energy consumers. Inputs/outputs
Inputs: Labor Fuel Electricity Track Drug Sugar Total
Total energy (MJ/hive) Beekeeping no. 32 (Minimum use)
Beekeeping no. 76 (Maximum use)
25.66 35.19 107.04 48.52 0.012 154 370.41
37.91 35.19 31.07 48.52 0.05 215.6 368.29
Table 4 Total input and output energy. Inputs/outputs Inputs: Labor Fuel Electricity Track Drug Sugar Output Honey
Total energy (GJ/hive)
2.24 2.82 4.71 3.88 0.003 15.29 15.26
Fig. 1. Frequency of specific energy value in beekeeping units.
specific energy values are showed in Fig. 1. Also, in Table 6, other values of energy are very low or poor. So the mean of total output energy and total net energy are 225058.14 MJ and 188238.56 MJ, respectively. However, at this point it should not be forgotten that honey production is not energy positive; more energy is needed in the production than the one the product has [32]. The frequencies of productivity of energy values are showed in Fig. 2. The fluctuations in specific energy and productivity of energy in beekeeping units indicate that there was no proper management of the production. In the initial analysis of the data, the reason for rejecting the claim that input values are normally distributed (Kolmogorov–Smirnov) didn't exist (p 40.01). The visual information in Figs. 1 and 2 were corroborated the lack of normal distribution. The annual total input and output energy in producers were calculated as 28.942 MJ hive 1 and 15.264 MJ hive 1, respectively. The results of the Analysis of Variance (ANOVA) indicated that the mean of energy efficiency in producers of honey was not significantly different within three groups (fewer than 1100 hives, 1100–1500 and more than 1500 hives) (p ¼0.239). Also, the analysis indicated that the sugar was the largest amount of input energy. On average, 12.41 kg of sugar per hive were used (Fig. 3 – the drug was ignored.). This amount of sugar contained 114.191 MJ of energy. The sugar, with a ratio of 2:1 or 1:1 (depending on the season) was mixed with water, to make sugar syrup for feed the bees. The total of sugar energy in all producers was 17995.67 GJ. More sugar consumption is needed in spring for the honey bees due to population increasing. Even if the population was low before winter, the concentrate of sugar syrup is added. A beekeeper uses 12 kg of sugar per hive (24 kg of sugar syrup with 1:1 ratio) usually annually. The results of input energy, output energy and energy indices are indicated in Table 6. The third level of sugar consumption has the maximum energy productivity and efficiency. In this level, 1.165 kg of honey was produced for each Mega
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Table 6 The results of input energy, output energy and energy indices. Sugar consumption (kg)
Producer number
Input energy (MJ/hive)
Output energy (MJ/hive)
Specific energy (MJ/kg)
Productivity (kg/MJ)
Efficiency (mean)
X o 12 12o xo 14 144 x
26 27 27
9388.412 9853.926 9699.167
4922.64 5088.00 5253.36
632.17 667.57 637.85
1.081 1.106 1.165
0.53 0.52 0.55
joule of energy used. For investigating the effect of energy inputs on output and conduct an analysis with the Cobb–Douglas production function, the coefficient of determination was calculated, being 0.977 (Table 7). The results showed that the fuel and sugar have the most important energy input with share of 51.0% and 46.1% of total energy (Fig. 4, left). These results indicate that, by adding 1% of sugar or fuel consumption, the honey production increases 0.52% or 0.48%, respectively (Fig. 4. right). The Cobb– Douglas function was obtained: LnðY i Þ ¼ 1:466 þ 0:523LnðX 1 Þ 0:064LnðX 2 Þ þ 0:005LnðX 3 Þ þ 0:482LnðX 4 Þ
Fig. 2. Frequency of productivity of energy in beekeeping units.
ð5Þ
where Y i denotes the yield level of the i-th beekeeper and X 1 , X 2 , X 3 and X 4 are energy of fuel, electricity, labor and sugar, respectively. In the Stepwise model, each input was analyzed and if it hasn't a significant effect in the regression, it was removed. In this case the coefficient of determination was calculated, being 0.976. The fuel and sugar were important inputs with 0.574 and 0.459 importance coefficients (Table 8). According to the Beta coefficient column, the regression equation was obtained: LnðY i Þ ¼ 0:842 þ 0:547LnðX 1 Þ 0:459LnðX 4 Þ
ð6Þ
4. Discussion According to the results, most of the honey manufacturers in Shahrekord were not explainable and affordable, according to the rate of use and energy efficiency. However, because honey production mainly occurs in normal weather conditions, there is no solution to improve sufficiently the production conditions in terms of weather problems. But in other part's production, the honey quality can be raised. Some of the main reasons for such a situation for the producers of honey are as follows: 1. Low cost of energy inputs. 2. Disorder and influenced activity of bees by the pollution, dust, and also intense radio waves like cell phone and compel beekeepers to settle and travel to distant places. 3. The indiscriminate use the sugar and fuel consumption. 4. Drought and the early summer heat. 5. Mismanagement of the energy consumption in other inputs.
Fig. 3. Inputs energy.
Table 7 The results of Cobb–Douglas model. Independent variables
Regression ratio
Standard ratio
t
(Constant) Fuel Sugar Electricity Labor
1.466 0.523 0.482 0.065 0.007
0.510 0.461 0.028 0.002
3.460n 7.776n 7.393n 1.824ns 0.436ns
n
ns
Significant in 1% level. Not significant.
The results showed that sugar was the largest input energy within the primary inputs in honey production. Specific energy values, energy productivity and the mean value of energy efficiency in honey manufacturers in this city, was 24.22 MJ kg 1, 0.04 kg MJ 1 and 54%, respectively. Within the relationship between energy inputs and efficiency, fuel consumption with 51.0% and sugar with 46.1% were the most important factors. Sugar consumption in the over 14 kg hive 1 group showed that for each MJ of energy, 1.165 kg of honey is produced. Correct management in the honey production and achieving goals in beekeeping, needs monitoring, and typically, manufacturers can be monitored by the beekeepers associations and relevant helping institutions. Considering the large negative value of net energy in honey production the important issue was that contrary to the popular belief in
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Fig. 4. Cobb–Douglas model, (right) honey production variation by the sugar and fuel increasing (left) diagram of the important factors affecting the performance. Table 8 Results in Stepwise model. Independent variables
Regression ratio
Standard ratio
t
(Constant) Fuel Sugar
0.842 0.547 0.459
0.535 0.463
3.777n 8.231n 7.124n
n
Significant in 1% level.
Iran, honey isn't the only output in bee-keepings. In developed countries the last revenues of beekeepers is due to honey, and their main income is obtained from the other bee products such as Royal Jelly, Propolis, Pollen and Bee Venom. In some countries pollinating bees in the farmers gardens are the main source of income and honey income will be mostly spent in production costs. Meanwhile, in Iran the only option for beekeepers is producing the honey. Problems of the hives and the transfer of beekeeper equipment between areas in different seasons, the lack of accommodation for bees and beekeepers, the lack of using bee culture in farm fields the idea of most gardeners that their product is damaged by bee activity, cell phone radiation and pollution, force the beekeepers further away from the cities, and apart from gardens and farms. However, research has showed that the bee activity can raise the tonnage of agricultural products in fruit gardens because of the pollination. On the other hand, farmers spraying without noticing the adjacent beekeepers cause the death of bees and the declining in the production of honey and other products. The phenomenon of dust has not been ineffective on the performance of beekeepers and it's became a problem in honey production in recent years in Iran. Another issue regarding the monitoring was the lack of study in some beekeepers, and the unfamiliarity with technical issues and beekeeping, like switching the queen in the exact time, knowledge about the true value of the properties of bee products and the lack of communication with universities and research centers.
5. Conclusion The following conclusions were drawn from the study: 1. The total energy consumption for honey production was 28.942 MJ hive 1. Sugar energy was found to be the biggest energy consumer among all energy sources. Adequate and proper use of sugar can help to reduce the sugar energy consumed in honey production. 2. Energy use efficiency for honey productions in Shahrekord were calculated as 0.54, which shows an inefficient use of energy in beekeeping. The energy ratio can be increased by decreasing the energy input consumption.
3. The impact of human labor energy input for honey production was significantly positive on yield. 4. Optimization is an effective tool to maximize the amount of productivity which can reduce the input energy use and production costs. So, the present study can be extended to specify efficient beekeepers from inefficient ones, determine wasteful uses of energy inputs by inefficient farmers and suggest the optimum amounts of each inputs to be utilized by each inefficient beekeeper from the input energy sources. 5. Mechanizing the beekeeper and entering advanced equipment production of bee products such as wax harvesting devices, venom harvesters and devices that use less energy inputs while have higher output yields, reforming the old hives with standard and modern hives, and replacing trim and young queens with old and native queens, together with the use of renewable energy sources such as solar energy or wind energy can raise the operation, energy efficiency and productivity of honey production.
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