Productivity and costs modeling for tree harvesting operations using chainsaws in plantation forests, Tanzania

  • Authors

    • Dos Santos Silayo Department of Forest Engineering, Faculty of Forestry and Nature Conservation, Sokoine University of Agriculture, P.O Box 3012, Morogoro, Tanzania
    • George Migunga Sokoine University of Agriculture
    2014-09-27
    https://doi.org/10.14419/ijet.v3i4.3407

  • Abstract

    With exemption of a few private forests, timber harvesting in most plantation forests in Tanzania is carried out by less skilled and less equipped crews. Newly recruited crews often learn from experienced ones which may not be doing it in the perfect way. Therefore estimation and projecting production and costs becomes a big problem to logging managers. This study was carried out to develop productivity and costs models for chainsaw operators in a learning experiment. The experiments were designed in clear felling operations. Three experiments were set where each crew category was studied using time study and work sampling techniques that involved studying crews before training, after training and after the break at an interval of three months. Descriptive statistics and modelling was performed for each crews’ performance. Specific crew’s productivity and costs models have been developed reflecting necessary and unnecessary delay times. Assessment of the production costs show that unit costs decreases with increasing productivity in each unit of measurement of the production rate. It is recommended that productivity and costs for two-man crosscut saw operators be studied and modelled since they are also the main cutting tools used in tree cutting in Tanzania.

    Keywords: Productivity, Cost, Timber Harvesting, Modelling, Chainsaw, Tanzania.

  • References

    1. T. Anton, Forest engineering and technology in private forest enterprises. [Http://www.fao.org/docrep/w3722e/w3722e13.htm#topofpage] (2002), site visited on 3/2/2004.
    2. S. A. Axelsson, The mechanization of logging operations in Sweden and its effect on occupational safety and health. Journal of Forest Engineering 9(2): (1998) 25 - 31.
    3. N. Brokaw, and T. Jill, the H for DBH. Forest Ecology and Management 129: (2000) 89 – 91. http://dx.doi.org/10.1016/S0378-1127 (99)00141-3.
    4. S. Chung, The learning curve and the yield factor: the case of Korea’s semiconductor industry. Applied Economics 33: (2001) 473 – 483. http://dx.doi.org/10.1080/00036840122474.
    5. R. G. Condit, Research in large, long-term tropical forest plots. Trends in Ecology and Evolution 10: (1995) 18-22. http://dx.doi.org/10.1016/S0169-5347 (00)88955-7.
    6. S. Conway, Work sampling. Another way to see where time goes. Forest Industries 95(12): (1968) 34-35.
    7. B. Cris, Common forest mensuration formulae. [http://sres-associated. anu. edu. au/ mensuration /Brackand Wood 1998/ EQUATION. HTM# Volumes]. (1999) site visited on 13/03/2007.
    8. FAO, Logging and log transport in tropical high forests. A manual on production and costs. Forestry development paper No. 18. Food and Agriculture Organization of the United Nations, Rome, Italy. (1974) 88 pp.
    9. FAO, Forest harvesting in natural forests of the Republic of Congo. Forest harvesting case study 7. [http:// www. fao.org/ docrep/ w5796E/ w5796E00. htm] (1997) site visited on 10/8/2009.
    10. D. Fjeld, and A. Granhus, Injuries after selection harvesting in multi-stored sspruce stands – the influence of operating systems and harvest intensity. Journal of Forest Engineering 9(9): (1998) 33 – 40.
    11. C. C. Hassler, S. T. Grushecky and C. B. LeDoux, The effects of group selection harvest size on logging productivity. Journal of Applied Forestry 17(2): (2000) 51-56.
    12. ILO, Introduction To Work Study, Third Revised Edition. International Labour Organization, Geneva. (1979) 441pp.
    13. E. Kallonga, A. Rodgers, F. Nelson, Y. Ndoinyo, and R. Nshala, Reforming environmental governance in Tanzania: natural Resource management and the rural economy. Non - Commissioned Paper presented at the inaugural Tanzanian biennial development forum 24th – 25th April 2003 at the Golden Tulip Hotel, Dar es Salaam Tanzania. (2003) 15pp.
    14. R. E. Malimbwi, and M. S. Philip, A compatible taper/volume estimation system for Pinus patula at Sao Hill Forest Project, Southern Tanzania. Forest Ecology and Management 27: (1989) 109 – 115. http://dx.doi.org/10.1016/0378-1127 (89)90033-9.
    15. W. Mendenhall, T. Sincich, T. L. Sincich, A Second Course in Statistics: Regression Analysis (6th edition). Prentice Hall, ISBN-10: 0130223239, (2003) 1028pp
    16. G. A. Migunga, Production rates and cost of different cutting methods in a Tanzania soft wood plantation. Dissertation for Award of MSc Degree at University of Dar es Salaam, Division of Agriculture, Forestry and Veterinary, Morogoro, Tanzania. (1982) 118pp.
    17. R. Mousavi, Comparison of Productivity, cost and environmental impacts of two harvesting methods in Northern Iran: short-log vs. long-log. Dissertation for Award of MSc Degree at the Finnish Society of Forest Science, Finish Forest Research Institute. Joensuu, Finland. (2009) 93pp.
    18. H. Pentti, Procurement of Timber for the Finnish Forest Industries. The Finnish Research Institute. Research Papers. (1995) 557pp.
    19. E. Philip, Comparison of efficiency and working conditions between privately and past publicly controlled logging operation. A case study of Sao Hill Forest Project. Dissertation for Award of MSc. Degree at Sokoine University of Agriculture, Morogoro, Tanzania. (2001) 124pp.
    20. M. S. Philip, Measuring Trees and Forests, 2nd edition. CAB International, Wallingford, UK. (1994) 310pp.
    21. I. Samset, Winch and Cable Systems. Dordrecht: Martinus Nijhoff/Dr. W. Junk Publishers. (1985) 540pp. http://dx.doi.org/10.1007/978-94-017-3684-8.
    22. I. Samset, Forest operations as a scientific discipline. Meddelelser fra Norsk institutt for Skogforsk 44(12): (1992) 1-48.
    23. D. A., Silayo, S. S. Kiparu, E. W. Mauya, and D. T. K. Shemwetta, Working conditions and productivity under private and public logging companies in Tanzania. Croatian Journal of Forest Engineering 31(1): (2010) 65 – 74.
    24. D.A. Silayo, G.A. Migunga, and D.T.K. Shemwetta, Learn by doing: Modelling the effect of training and job interruptions on tree cutting time for chainsaw operators in plantation forests, Tanzania. Industrial Engineering Letters, 4 (7): (2014) 1-16.
    25. URT, National Strategy for Growth and Reduction of Poverty (NSGRP). Vice President’s Office. United Republic of Tanzania. Government Printers, Dar Es Salaam. (2005) 73p.
    26. A. Wolf, S. Davies and R. Condit, Ecological insights from long-term research plots in tropical and temperate forests. Bulletin of the Ecological Society of America 90: (2009) 519–525. http://dx.doi.org/10.1890/0012-9623-90.4.519.

  • Downloads

  • How to Cite

    Silayo, D. S., & Migunga, G. (2014). Productivity and costs modeling for tree harvesting operations using chainsaws in plantation forests, Tanzania. International Journal of Engineering & Technology, 3(4), 464-472. https://doi.org/10.14419/ijet.v3i4.3407

    Received date: 2014-08-20

    Accepted date: 2014-09-14

    Published date: 2014-09-27