- Email: [email protected]
Energetics of cotton agronomy
Energy Vol. 17, No. 5, pp. 493-497. 1992 Printed in Great Britain. All rights reserved
0360-5442/92 $5.00 + 0.00 Copyright @ 1992 Pergamon Press plc
ENERGETICS
OF COTTON AGRONOMY
A. R. RAO,~ D. S. NEHRA,$ D. P. SINGH,§ and M. S.
KAIRON~~
t Department of Veterinary Physiology, $ Plant Breeding, 5 Directorates of Farms, and 11Extension
Education, Haryana Agricultural University, Hisar-125 004, India (Received 23 October 1990; received for publication 9 August 1991)
Abstract-Agronomic data from a sample hectare of cotton-growing area of our farm were examined for energy inputs, outputs and balance for comparison with monetary values. Mechanized farming consumed about 45% of the energy inputs and accounted for about 20% of the expenses. The major cost (534 o) was for manpower, which accounted for about 5% of the energy inputs. Irrigation consumed about 30% of the energy inputs but cost only 1%. Fertilizers cost about 6% and accounted for about 12% of energy inputs. Insecticide use consumed under 6% of the energy used but cost about 16%. The total energy inputs were 10,475 Meal and resulted in an output of 30,107 Meal, a gain of a factor of 2.87. Cotton sticks provided about double the entire needed energy inputs.
INTRODUCTION
Agricultural enterprises have been evaluated earlier only in monetary terms. In view of energy constraints in the economies of countries the world-over, the agronomy of cotton has been subjected to a similar analysis by us. Energy inputs in production agriculture are often considered only as fuels or materials derived from fuels (such as fertilizers). The enormous input of solar energy is of little consequence because alternative options for its utilization in any terrestrial area are usually regarded as limited. This approach is adequate for situations where energy sources are only common fuels such as oil products, electricity, etc. However, in the LDCs including India, the role of non-commercial sources of energy and power is important and their applications in various rural or urban activities are diverse. In several situations, the entire input of production agriculture consists only of these non-commercial sources of power and energy. In such a situation, an assessment of energy utilization in agriculture by the common western model will be grossly inadequate. We have discovered anomalies in using standard methods to compute energy utilization in Indian agriculture.’
DATA
INPUTS
Physical data were obtained from a sample hectare of the experimental farm of the Haryana Agricultural University, Hisar. The agronomic practices used in this area are generally consistent with good agricultural practices in Haryana. The operations, materials and manpower utilization, as well as costs, have been recorded. The data have been transformed into energy units, essentially according to the methods of others.‘-” RESULTS
AND
DISCUSSION
Observations and their transformations into energy units are shown in Tables 1-5. The methods used for these transformations are described in the table headings. Table 6 shows energy inputs and comparisons with their rupee values; there are some disparities between monetary and energy values as percentages of inputs. Land preparation cost only 20% of the total inputs. Fertilizers and irrigation appear to be under-priced, while insecticides appear to 493
A. R. RAO et al
494
Table 1. Mechanized operations. The fixed energy inputs for tractor use and ancillary equipment have been taken to be 47.44 Meal/h.’ Operation Harrowing Levelling Ridge making Planking Sowing Interculture Transportation
Time (h)
Meal
24 8 0.7 0.7 2.1 5.4 8
@ 47.44/h
Table 2. Fuel consumption. The consumption of diesel, oil and lubricants by a 20-25 h.p. tractor is about 4.0 I/h. The total fuel consumption has been estimated on this basis and its embodied energy (combustion value, plus energy used for production and transportation) is taken to be 11.4 Meal/I as in the U.S.” Fuel used Diesel, lubricants, etc.
Litres
Meal
190
2230
Table 3. Some inputs. Item Seed? Urea$ Irrigations
Quantity
Meal
20 kg 200 kg 44cm
287 1320 3136
tThe gross energy content of cotton-seed is’ 5291 Meal/kg and is multiplied by the ratio of the prices of cotton-seed of sowing variety to that of cotton-seed of feed quality (2.71) according to the method used by Pimente1.s $ The energy incorporated into urea has been computed and adopted to be 6.6 Meal/kg urea.s 8 The total energy consumed per hectare was estimated to be 71.4 Meal/cm.’
Table 4. Pesticide use. Calculated from price ratios per spray over with DDT, inclusive of inputs in manufacture, formulation, transportation, etc. by manual spraying using a knapsack sprayer.* Pesticide
Dimecron Monocrotophos Monocrotophos Endosulphan Ekalux Total
Quantity (g of active ingredient)
Meal
212 500 600 700 625
27.019 99.300 118.573 100.277 133.474 597.216
495
Energetics of cotton agronomy Table 5. Manpower use. Energy inputs through human labour are taken to be the dietary energy (3.9Mcal/day) needed for a man doing hard labour for 8 h/day.’ Operation Land preparation Sowing Weeding Spraying Irrigation Other operations Cotton picking Total -
Man-days
Meal
2 2 34 12 12 29 60
7.8 7.8 132.6 46.8 46.8 113.1 234.0
151
588.9
Table 6. Summary of inputs; 1 U.S.$ = 18 Rs. Inputs
Cost
Energy
(Rs.)
(%)
(Meal)
(%)
Cultivation Diesel Seed Fertilizers Insecticides Irrigation Manpower
1250 195 410 977 63 3300
20 3 7 16 1 53
2320 2230 287 1320 597 3136 585
22 21 3 13 6 30 6
Total
6195
10,475
Energy balance of cotton cultivation (per hectare)
I
25
Total outputs 30.1 mill.
Q) P, 20
Total inwts 10.5 mill.
= 15 8 -* "0 5
10
5
0
Fig. 1. Energy balance of cotton cultivation per hectare
1
4%
A. R. RAO et al Table 7. Outputs. outputs By-products 1. Cotton sticks? 2. Cotton-seed oils 3. Cotton-seed cakes
kg
5OLxl 264 936
Total
MCal
20785 2376 4305.6 27466.6
Main product 1. Cotton fibrell
600
2640
tGross energy = 4.157 Meal/kg.’ *Dietary value = 9 Mcal/kg.3 OGross energy = 4.6 Meal/kg.’ “Estimated at 4.4 Meal/kg.‘*
cost much more than the energy embodied in the gains resulting from their use. It is interesting to note that human energy in the form of dietary energy of the labourers forms a very small percentage of the energy inputs but accounts for more than half of the cost of cultivation. This process may be socially justified, but one wonders if more effort should not go into looking for alternatives to manpower in the cultivation of cotton. The total energy inputs for the cultivation of cotton are about 10.5 x lo6 kcal/ha. In Haryana, on average, the inputs for the cultivation of other crops vary from 10.5 to 41.8 million kcal/ha of maize,4 7.9 to 11.2 million kcal/ha of paddy,” 9.2 million kcal/ha for Mexican wheat,” and 15.9 to 40.1 million kcal/ha of sugarcane.’ The output-input ratios for energy as grains/main product were 0.06-0.28 and of total biomass 0.29-1.16 in maize;4 0.76-0.90 and 3.32-3.57 in two varieties of rice and in wheat the grain ratio was 0.99, while the biomass yield was 2.47.” Similarly, in sugarcane cultivation, the sugar yield was 0.52-1.03 and that of the total biomass 1.54-3.03.5 For comparison, the yield of cotton observed in these experiments formed 0.25 and the total biomass 2.87 of the agricultural energy inputs. This analysis of energy utilization and productivity in Indian agriculture9 suggests the relative emphasis which should be placed on cotton in view of constraints on energy supplies. The various outputs of the cotton crop have been evaluated and are described in Table 7. Cotton sticks, being the largest output, constitute the largest sources of energy and equal about double the entire energy inputs. The energy of cotton sticks is fully utilized as fuel in rural areas. Additional energy is obtained in the form of a respectable quantity of cotton-seed oil. In fact, the yield of cotton-seed oil/ha appears to be higher than that from mustard (about 250 kg of oil/ha), which is the locally comparable oilseed crop. Cotton-seed cake is rich in proteins. It is fit for direct use in the diet of ruminants and can even be purified for consumption by babies. The yield of protein per hectare from a crop of cotton is 239 kg while that from a crop of Bengalgram (Cicer arietinum L., legume grain, average yield = 6.25 Q/ha, 18.1% protein) works out to be only 113 kg. In view of the energy yields from the by-products, we may consider the cotton-fibre energy as a bonus. We may also evaluate the energy inputs per kg of cotton, ignoring all by-products. We find 19,120 kcal of inputs/kg of cotton fibre. The present results indicate that cotton cultivation has favourable energy benefits and need not be considered to be a drain on non-renewable fossil-energy resources because fertilizers and pesticides require such raw materials. REFERENCES 1. A. R. Rao, Appl. Energy 30, 235 (1988).
Energetics of cotton agronomy
497
2.E. W. Crampton and L. E. Harris, Applied Animal Nutrition, 2nd edn, Freeman, San Francisco, CA (1%9). 3. C. Gopalan, B. V. Ramasastri, and S. C. Balasubramanian, Nutritive Values of Indian Fooak, National Institute of Nutrition, Hyderabad (1971). 4. R. S. R. Gupta, H. S. Malik, R. K. Malik, and A. R. Rao, Energy-The International Journal 9, 189 (1984). 5. R. K. Malik and A. R. Rao, Energy-The International Journal 8, 291 (1983). 6. R. K. Murty, A Manual on Compost and Other Organic Manures, Today and Tomorrow Publishers, New Delhi (1978). 7. B. S. Pathak, and A. K. Jain, Characteristics of Crop Residues, Punjab Agricultural University, Ludhiana (1984). 8. D. Pimentel, Handbook of Energy Utilization in Agriculture, CRC Press, Boca Raton, FL (1980). 9. A. R. Rao, Energy-The International Journal 10,911(1985). 10. S. Brody, Bioenergetics and Growth, Hafner, New York, NY (1945). 11. A. R. Rao and R. K. Malik Vrja (Indian J. Energy) 11,279(1982).
EGY 17:5-F
0360-5442/92 $5.00 + 0.00 Copyright @ 1992 Pergamon Press plc
ENERGETICS
OF COTTON AGRONOMY
A. R. RAO,~ D. S. NEHRA,$ D. P. SINGH,§ and M. S.
KAIRON~~
t Department of Veterinary Physiology, $ Plant Breeding, 5 Directorates of Farms, and 11Extension
Education, Haryana Agricultural University, Hisar-125 004, India (Received 23 October 1990; received for publication 9 August 1991)
Abstract-Agronomic data from a sample hectare of cotton-growing area of our farm were examined for energy inputs, outputs and balance for comparison with monetary values. Mechanized farming consumed about 45% of the energy inputs and accounted for about 20% of the expenses. The major cost (534 o) was for manpower, which accounted for about 5% of the energy inputs. Irrigation consumed about 30% of the energy inputs but cost only 1%. Fertilizers cost about 6% and accounted for about 12% of energy inputs. Insecticide use consumed under 6% of the energy used but cost about 16%. The total energy inputs were 10,475 Meal and resulted in an output of 30,107 Meal, a gain of a factor of 2.87. Cotton sticks provided about double the entire needed energy inputs.
INTRODUCTION
Agricultural enterprises have been evaluated earlier only in monetary terms. In view of energy constraints in the economies of countries the world-over, the agronomy of cotton has been subjected to a similar analysis by us. Energy inputs in production agriculture are often considered only as fuels or materials derived from fuels (such as fertilizers). The enormous input of solar energy is of little consequence because alternative options for its utilization in any terrestrial area are usually regarded as limited. This approach is adequate for situations where energy sources are only common fuels such as oil products, electricity, etc. However, in the LDCs including India, the role of non-commercial sources of energy and power is important and their applications in various rural or urban activities are diverse. In several situations, the entire input of production agriculture consists only of these non-commercial sources of power and energy. In such a situation, an assessment of energy utilization in agriculture by the common western model will be grossly inadequate. We have discovered anomalies in using standard methods to compute energy utilization in Indian agriculture.’
DATA
INPUTS
Physical data were obtained from a sample hectare of the experimental farm of the Haryana Agricultural University, Hisar. The agronomic practices used in this area are generally consistent with good agricultural practices in Haryana. The operations, materials and manpower utilization, as well as costs, have been recorded. The data have been transformed into energy units, essentially according to the methods of others.‘-” RESULTS
AND
DISCUSSION
Observations and their transformations into energy units are shown in Tables 1-5. The methods used for these transformations are described in the table headings. Table 6 shows energy inputs and comparisons with their rupee values; there are some disparities between monetary and energy values as percentages of inputs. Land preparation cost only 20% of the total inputs. Fertilizers and irrigation appear to be under-priced, while insecticides appear to 493
A. R. RAO et al
494
Table 1. Mechanized operations. The fixed energy inputs for tractor use and ancillary equipment have been taken to be 47.44 Meal/h.’ Operation Harrowing Levelling Ridge making Planking Sowing Interculture Transportation
Time (h)
Meal
24 8 0.7 0.7 2.1 5.4 8
@ 47.44/h
Table 2. Fuel consumption. The consumption of diesel, oil and lubricants by a 20-25 h.p. tractor is about 4.0 I/h. The total fuel consumption has been estimated on this basis and its embodied energy (combustion value, plus energy used for production and transportation) is taken to be 11.4 Meal/I as in the U.S.” Fuel used Diesel, lubricants, etc.
Litres
Meal
190
2230
Table 3. Some inputs. Item Seed? Urea$ Irrigations
Quantity
Meal
20 kg 200 kg 44cm
287 1320 3136
tThe gross energy content of cotton-seed is’ 5291 Meal/kg and is multiplied by the ratio of the prices of cotton-seed of sowing variety to that of cotton-seed of feed quality (2.71) according to the method used by Pimente1.s $ The energy incorporated into urea has been computed and adopted to be 6.6 Meal/kg urea.s 8 The total energy consumed per hectare was estimated to be 71.4 Meal/cm.’
Table 4. Pesticide use. Calculated from price ratios per spray over with DDT, inclusive of inputs in manufacture, formulation, transportation, etc. by manual spraying using a knapsack sprayer.* Pesticide
Dimecron Monocrotophos Monocrotophos Endosulphan Ekalux Total
Quantity (g of active ingredient)
Meal
212 500 600 700 625
27.019 99.300 118.573 100.277 133.474 597.216
495
Energetics of cotton agronomy Table 5. Manpower use. Energy inputs through human labour are taken to be the dietary energy (3.9Mcal/day) needed for a man doing hard labour for 8 h/day.’ Operation Land preparation Sowing Weeding Spraying Irrigation Other operations Cotton picking Total -
Man-days
Meal
2 2 34 12 12 29 60
7.8 7.8 132.6 46.8 46.8 113.1 234.0
151
588.9
Table 6. Summary of inputs; 1 U.S.$ = 18 Rs. Inputs
Cost
Energy
(Rs.)
(%)
(Meal)
(%)
Cultivation Diesel Seed Fertilizers Insecticides Irrigation Manpower
1250 195 410 977 63 3300
20 3 7 16 1 53
2320 2230 287 1320 597 3136 585
22 21 3 13 6 30 6
Total
6195
10,475
Energy balance of cotton cultivation (per hectare)
I
25
Total outputs 30.1 mill.
Q) P, 20
Total inwts 10.5 mill.
= 15 8 -* "0 5
10
5
0
Fig. 1. Energy balance of cotton cultivation per hectare
1
4%
A. R. RAO et al Table 7. Outputs. outputs By-products 1. Cotton sticks? 2. Cotton-seed oils 3. Cotton-seed cakes
kg
5OLxl 264 936
Total
MCal
20785 2376 4305.6 27466.6
Main product 1. Cotton fibrell
600
2640
tGross energy = 4.157 Meal/kg.’ *Dietary value = 9 Mcal/kg.3 OGross energy = 4.6 Meal/kg.’ “Estimated at 4.4 Meal/kg.‘*
cost much more than the energy embodied in the gains resulting from their use. It is interesting to note that human energy in the form of dietary energy of the labourers forms a very small percentage of the energy inputs but accounts for more than half of the cost of cultivation. This process may be socially justified, but one wonders if more effort should not go into looking for alternatives to manpower in the cultivation of cotton. The total energy inputs for the cultivation of cotton are about 10.5 x lo6 kcal/ha. In Haryana, on average, the inputs for the cultivation of other crops vary from 10.5 to 41.8 million kcal/ha of maize,4 7.9 to 11.2 million kcal/ha of paddy,” 9.2 million kcal/ha for Mexican wheat,” and 15.9 to 40.1 million kcal/ha of sugarcane.’ The output-input ratios for energy as grains/main product were 0.06-0.28 and of total biomass 0.29-1.16 in maize;4 0.76-0.90 and 3.32-3.57 in two varieties of rice and in wheat the grain ratio was 0.99, while the biomass yield was 2.47.” Similarly, in sugarcane cultivation, the sugar yield was 0.52-1.03 and that of the total biomass 1.54-3.03.5 For comparison, the yield of cotton observed in these experiments formed 0.25 and the total biomass 2.87 of the agricultural energy inputs. This analysis of energy utilization and productivity in Indian agriculture9 suggests the relative emphasis which should be placed on cotton in view of constraints on energy supplies. The various outputs of the cotton crop have been evaluated and are described in Table 7. Cotton sticks, being the largest output, constitute the largest sources of energy and equal about double the entire energy inputs. The energy of cotton sticks is fully utilized as fuel in rural areas. Additional energy is obtained in the form of a respectable quantity of cotton-seed oil. In fact, the yield of cotton-seed oil/ha appears to be higher than that from mustard (about 250 kg of oil/ha), which is the locally comparable oilseed crop. Cotton-seed cake is rich in proteins. It is fit for direct use in the diet of ruminants and can even be purified for consumption by babies. The yield of protein per hectare from a crop of cotton is 239 kg while that from a crop of Bengalgram (Cicer arietinum L., legume grain, average yield = 6.25 Q/ha, 18.1% protein) works out to be only 113 kg. In view of the energy yields from the by-products, we may consider the cotton-fibre energy as a bonus. We may also evaluate the energy inputs per kg of cotton, ignoring all by-products. We find 19,120 kcal of inputs/kg of cotton fibre. The present results indicate that cotton cultivation has favourable energy benefits and need not be considered to be a drain on non-renewable fossil-energy resources because fertilizers and pesticides require such raw materials. REFERENCES 1. A. R. Rao, Appl. Energy 30, 235 (1988).
Energetics of cotton agronomy
497
2.E. W. Crampton and L. E. Harris, Applied Animal Nutrition, 2nd edn, Freeman, San Francisco, CA (1%9). 3. C. Gopalan, B. V. Ramasastri, and S. C. Balasubramanian, Nutritive Values of Indian Fooak, National Institute of Nutrition, Hyderabad (1971). 4. R. S. R. Gupta, H. S. Malik, R. K. Malik, and A. R. Rao, Energy-The International Journal 9, 189 (1984). 5. R. K. Malik and A. R. Rao, Energy-The International Journal 8, 291 (1983). 6. R. K. Murty, A Manual on Compost and Other Organic Manures, Today and Tomorrow Publishers, New Delhi (1978). 7. B. S. Pathak, and A. K. Jain, Characteristics of Crop Residues, Punjab Agricultural University, Ludhiana (1984). 8. D. Pimentel, Handbook of Energy Utilization in Agriculture, CRC Press, Boca Raton, FL (1980). 9. A. R. Rao, Energy-The International Journal 10,911(1985). 10. S. Brody, Bioenergetics and Growth, Hafner, New York, NY (1945). 11. A. R. Rao and R. K. Malik Vrja (Indian J. Energy) 11,279(1982).
EGY 17:5-F