3. SUMMARIES OF CASE STUDY PRESENTATIONS
The institute of Agricultural and Environmental Engineering (IMAG-DLO) is part of the Agricultural Department of The Netherlands Government The Department of Development Cooperation within IMAG-DLO works in countries in Africa and Asia and concentrates on animal traction and crop processing technologies. IMAG-DLO in partnership with the Ministry of Agriculture in Zambia is developing alternative tillage systems in order to improve conservation of rainwater and soil, to improve timeliness of planting, and to cope with reduced availability of draft power. The research resulted in the development of the following animal drawn conservation tillage equipment:
All implements are low-cost, durable attachments, which can be easily interchanged with the plough body on any commonly available, standard plough beam. It was realized that when introducing these conservation tillage tools on smallholder farms, weeding would become an even more critical aspect than it already is in the conventional ploughing system.
Herbicides are beyond the reach of most farmers and the availability of, and effective mulch cover is not guaranteed. Mechanical weeding with draft animals is a practical option to keep the weed problem under control. Another tool, which can be used for weeding is the ripper-ridger which is the ripper attachment fitted with a pair of adjustable wing extensions and an optional radar. All equipment is designed to enable local manufacture in the region and is currently produced by a manufacturer in Zambia. Conservation Tillage for Sustainable Crop Production Systems Highlights of results and experiences from on-station and on-farm research in Zimbabwe (1988-1997).
"Conservation Tillage For Sustainable Crop Production Systems" was a Zimbabwe collaborative project between the Department of Agricultural, Technical and Extension Services (AGRITEX) and the Germany Agency for Technical Cooperation (GTZ). The project was initiated in response to extensive problems of soil loss and run-off, which were being experienced by smallholder farmers (Elwell and Stocking, 1988; Whitlow, 1988). The primary objective of the project was to assess the yield merits of several conservation tillage systems with a view to the development of sustainable smallholder crop production systems in different agro-ecological regions. Two maize experimental sites were established on sandy soils under natural rainfall at Domboshawa Training Centre and at Makoholi Experiment Station. Soils on both sites are shallow granite-derived sands with clay content lower than 5%. Tillage Systems. The four tillage system under investigation were:-
The trials considered soil loss, run-off and maize yields, organic carbon and weed control. The research adopted a farmer participatory research and extension approach known as "Kuturaya". Major findings and conclusions included:
Socio - economic factors affecting the adoption of conservation tillage Experience from the soil and water conservation and agroforestry program, SWaCAP , Lesotho
Introduction SWaCAP, a joint Lesotho - IFAD program was established as an intervention to encourage conservation based agricultural production practices. It covered extension in Northern District and agroforestry research and policy coordination in the rest of the country. The programme was terminated in June 1998. SWaCAP was established as a means to boosting agriculture, in recognition of the poor economic situation. This was partly due to reduced remittances from miners in South Africa and rising unemployment and droughts of 1990s. Mining saw a situation where 63% of the households were without men, a major source of labour shortage especially for animal power utilization. Lesotho has more than 80% rangeland, 67% of which is highland. Arable land has decreased from 14% in the 70s to 9% in the 90s. Yields have been on a decreasing trend despite increased use of fertilizer. SWaCAP’s main goal: To promote conservation based agricultural production systems within a framework of client-demand, extension approach. Specifically SWaCAP was to:
Constraints: Poor soils combined with unpredictable weather conditions. Inadequate moisture for crops during the growing season; high cost of inputs (inorganic fertilizers and hybrid seeds), and late planting due to inadequate (few & poor in health) draft animals and/or tractors. Interventions: Rip-line system, conservation tillage practice to conserve water in-situ and make it available to the crop over a longer period. The system though successful and popular was limited by soil type and animal power availability. Concerns about Rip-Line were such as:
Tied-ridges and minimum tillage techniques were tried, without much success. Conservation farming in smallholder farming systems: Palabana
Farm Power and Mechanization Centre
Through a participatory on-farm trial process, the Palabana Farm Power and Mechanization Centre has taken up to develop and provide mechanization inputs in the application of conservation farming with animal power systems. The centre has successfully adapted a ripper, a sub-soiler and a ripper-planter. These technologies are getting popular with farmers. The main objective of the Palabana intervention was to develop and make available technologies that would enable farmers:
Main issues and experiences Over the years Palabana experiences with trials of different equipment developed to a shift from timely planting to soil conserving technologies. This is because much more than fertilizer and apparent soil degradation was affecting yields. The broader approach included consideration of:
This led to the development and promotion of the:
Zambia went through the adaptability phase of technology transfer with relative ease as the equipment showed, not immediate but shorter-term gains of change in tillage practice. Among other longer-term issues, farmers liked the gains in terms of:
Conservation tillage research and development in South Africa ARC-Grain
Crops Institute
South Africa has a total area of over 122 million hectares, of which only one third is level to moderately slopping and only 14% is arable. Only 3% of the arable area is classified as being of high agricultural potential. Almost 60% of the soils have very low organic matter content, and are conducive to land degradation and low productivity. South African tillage principles and practices have been almost exclusively derived from those utilized in Europe and North America. The main focus in this tillage was to prepare a good seedbed, free from weed and surface trash. In pre-1950 agriculture the ox was still the main source of traction with ploughing as the main tillage operation. The large heavy tine cultivators were being introduced to take the place of the plough in some cases. Tines were also used especially on the heavy turf soils of the springbok flats. Such fields were ploughed only once every 2-3 years. In post-1950 agriculture surface pulverization by raindrops, solar desiccation and heating, and trampling by stock had been identified as the most important factors contributing to the physical decline of soils. Noted possible solutions to these problems were:
Conservation tillage in maize production involved mulching and reduced tillage using chisel ploughs. Ripping on sandy soil to depths of 450mm produced more significant increase in yield during low rainfall years. Other factors that influenced sustained fertility of the soil included:
It was concluded that despite considerable research and development work in South Africa, there are gaps in the information available and this is a main constraint to adoption of conservation tillage, technologies. Much of this knowledge has still to be effectively digested and presented to users. Aspects such as crop rotations, animal power applications still need more research. However, research efforts are being hampered by:
The Role of Draft Animal Power in Ghanaian Agriculture by Emmanuel Y.H. Bobobee Agricultural
Engineering Department Kumasi,Ghana. Draft animal power in Ghana was first introduced into the dryer North of the country in the 1930s mostly by British Settlers. This was to support the production of cereals and other export crops. Until the late 1950s animal power use grew popular even with local farmers. With independence in 1957 government policies shifted to support tractor mechanization and this considerably reduced interest in the use of animal power technologies. Due to many reasons, including the collapse of the tractor programs, use of animal power is currently on a rapid up-swing. Most work animals are bullocks with over 35,000 pairs of oxen out of a total herd of about 1.2 million in use.
Nearly 15,000 donkeys are also in use especially on single donkey carts. There is increasing interest to use donkeys even for ploughing and ridging. The Tamale Implement Factory and local blacksmiths make most implements, the majority of which are ploughs. Most such ploughs have problems with the beam and those from blacksmiths lack proper finish. Some socio-economic research relating to animal traction has been conducted. However, systematic testing and durability trials, research and development of animal drawn implements have not developed. Most frontline staff have limited skills and exposure in animal traction. Training for both staff and farmers at Farm Institutes and Agricultural Colleges is frustrated by lack of facilities including animals, implements,teaching manuals, other materials as well as experienced instructors. Appropriate animal traction extension materials are almost non-existent. Despite many years of neglect, animal traction is still a major farm power component especially in Northern Ghana. Animal traction, still offers the best opportunities for increase in farm size, reducing drudgery in farm work, reducing labor costs, raising yields and farm production in general. However, some issues have to be addressed as pre-conditions. These include:
Editors Note: This paper was presented to bring in the case of Ghana and it had not been prepared specifically for Conservation Tillage. The author however made the case of the existing potential for CONTIL practices in Ghana as anywhere else in Africa.
Rainwater Harvesting Technologies for Agricultural Production: A Case for Dodoma Tanzania by N. Hatibu
and N. Mahoo
Rainwater harvesting (RWH) was defined as the method of inducing, collecting, storing and conserving local surface runoff for agricultural production. The presenter viewed RWH as a resort solution, especially in drought prone areas, where irrigation and other means of sourcing the benefits of water were not possible or economical. Presenting a brief treatise of the basis of rainwater harvesting, the paper reviewed major techniques of RWH as practised in crop production. The practices fell in three broad categories:
Referring to Dodoma the presenter noted in-situ RWH techniques were in use but only in areas where deep tillage was possible, using both animal power and tractors. In Kondoa District draft animals are the main source of power, used for deep primary tillage. Much of the draft animal power capacity available in Dodoma is idle due to shortage of traditional experience, exposure and appropriate equipment for utilizing animal power. The Internal (Micro) Catchment RWH method used in Dodoma takes the form of contour bunds, a system widely promoted by extensionists. Some 775 km of bunds were constructed over a period of 10 years beginning 1984. While other methods are absent in Dodoma the Meskat-type system is in use. Regarding the External (Micro) Catchment, the Hillside Sheet and Runoff utilization method is commonly used. The paper concluded by looking at the past, current approaches and the role of RWH in Dodoma region. The appropriate techniques and their relative viability was also highlighted.
Indigenous conservation tillage systems in East Africa; An example of their evaluation from South West Tanzania B. Kayombo, J. Ellis-Jones, H.L. Martin
Available literature in East Africa reveals that indigenous conservation techniques (ICT) are prevalent in areas of water-deficit conditions and in semi-arid zones. Due to changing natural and socio-economic environment, some of these ICT systems are beginning to show signs of decline. The need to understand these systems as a step to their improvement (and hence reverse the declining trend) is paramount.
The Ngoro approach to soil and water conservation is a common ICT in Mbinga District of South West Tanzania. It has shown that Ngoro cultivation is efficient at controlling soil erosion, increasing soil moisture at critical times of the year and maintaining soil fertility. However the Ngoro has problems associated with it, notably decreasing fallow periods and high labour requirement. The socio-economic evaluation of ICT techniques in Mbinga District indicate declining use. The technical evaluation has shown that when Ngoros are intact, they increase soil moisture and consequently bean yields, compared to ridges. When badly degraded, soil moisture is decreased but despite this, maize growth and yield are better than on ridges when no fertilizer is used. In the Ngoro, the majority of eroded soil is redeposited into the pit, whereas on ridges it is often transported elsewhere. The immediate future challenge is to build productivity enhancing improvements into the present system without destroying its unique advantages.
Participatory Extension of conservation tillage techniques: Edward Chuma, Kudakwashe Murwira and Juergen Hagmann
The presenter reported that rampant soil erosion and land degradation continue to destroy the agricultural base of Zimbabwean farming. This land management crisis has been attributed to the poor adoption research proven techniques for soil and water management. Both on - station and on-farm research had received very little impact, mainly due to poor integration of on-farm research with disciplinary and commodity research as well as weak links with extension services. In response to the above constraints, the AGRITEX-GTZ conservation tillage research project and the IntermediateTechnology Group, Food Security Extension Project initiated the development of a farmer participatory technology generation approach. This approach, locally referred to as "Kuturaya" was built on combining farmers indigenous knowledge with Western knowledge. It aimed at facilitating the development and spread of sustainable farming practices while enabling rural communities and individual families to solve their own problems. The conceptual model of Kuturaya was based on "Training for Transformation" concept and consisted of research, extension and active farmer participation components. The implementation model consisted of three major components, which were closely inter-linked. These were:
A preparatory phase was essential and took place before "Kuturaya" was initiated. This included assessment of agro-ecological, socio-economic and farming system details using Participatory Rural Appraisal (RRA) tools. In Conclusion the presenter noted that the application of "Kuturaya" has initiated a participatory process with new potential to tap indigenous knowledge held by farmers. To increase impact and sustainability, the approach needs to be institutionalized. For longer term impact a change of attitude of all players involved is required as well as integration of the approach into a wider community resource management concept.
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