1.1 General
Whenever a new, alien technology is introduced in a system, new risks and dangers are also introduced. Agriculture in Sub-Saharan Africa has had more than its fair share of introduction of inappropriate technologies that either did not serve their purpose at all, or had too many unwanted and unforeseen side effects. There have been numerous efforts to introduce mechanization in African farm practices, but most met with limited success, and some with complete failure. All in all, the mechanization issue is one of controversy. One of the major forms of mechanization is the use of engine powered machines for tillage. Tillage is a process that generally requires a lot of power input and the lack of farm power is often argued to be one of the main constraints for the growth of agricultural production. On the other hand, there is the argument that the adverse environmental effects of intensified soil tillage as a result of mechanization are crucial. The main drawbacks are the potential for increased erosion and soil degradation, problems which are already rampant over many of the fragile African soils. In addition, tractor use has been criticised for its undesirable social impact, particularly for the displacement of labour in conditions of general unemployment. The sustainable introduction of tractors has been, more often than not, hindered by poor institutional support, poor spare part supplies and high maintenance costs for low-income farmers. As the issue of tractorization and the resulting intensification of tillage becoming increasingly controversial, tillage systems that aim at minimizing soil disturbance have gained popularity rapidly. Conservation tillage, minimum tillage and zero tillage are now being researched and promoted worldwide. Currently, the scale on which mechanical power is used for tillage is still limited. In Africa, 80% of the cultivated land is currently prepared by hand, using human muscle power to do the work. On 16% of the land animal draught power is used and only 4% is prepared with mechanical power (Mrema, 1996). The number of tractors has been growing over the last decades and this small percentage is likely to increase, with or without the aid of donors and governments. With the advantages, and more importantly the risks and drawbacks in mind, the process of tillage mechanization is one that needs to be monitored and guided closely to judge whether or not mechanization in its current form is the path that leads to a sustainable increase in production. This study seeks to investigate the current status of motorized tillage in West-Africa and the pros and cons of it, as perceived by specialists working in this field. 1.2 Terminology in mechanisation In the terminology in the area of mechanization, motorization and tractorization there is reason for confusion. Mechanical tillage can comprise both tillage with animals and with engine power. Mechanical power however, is always provided by an engine. In accordance with the most widely used terminology, this report uses the terms as follows: Mechanization: introduction of machines into a system; here it comprises the introduction of implements for both motorized and animal traction Motorization: introduction of engines into a system, it comprises the introduction of engine-powered machinery Tractorization: introduction of tractors into a system Mechanical traction: traction provided by motorized machines (power tillers and tractors) Animal traction: traction provided by animals Mechanical tillage: tillage with implements being drawn by either motorized machines or animals Thus agricultural motorization concerns the use of engine powered machinery for carrying out agricultural activities. In more detail, it comprises:
This paper however, concentrates on motorization for tillage. Since only tractors and power tillers are used in West African practice for motorized tillage, the other forms will be left out of consideration.
1.3 Methodology of study
The basis of this research derives from a questionnaire. The Agricultural Engineering Branch of FAO has created a questionnaire that was sent to 110 addresses in 17 countries in West Africa.
The addresses used were obtained from various sources, including: participant lists of various workshops and seminars, the SPAAR directory of Agricultural Research Institutions in Africa published by the Worldbank, the International Directory of Agricultural Engineering Institutes elaborated by FAO and various other sources. An effort was made to include the relevant departments and units of respective Ministries of Agriculture in the mailing list.
The processing of the completed questionnaires was done by hand. In total 14 questionnaires out of 110 were returned, representing a 13% response rate. From 7 out of the 17 countries, at least one questionnaire was received. The countries that did not respond are: Niger, Guinea-Bissau, Cap Verde, Burkina Faso, Sierra Leone, Nigeria and Liberia. The results of the questionnaire have been combined with a literature study.