Upon completing my work in Mvumi I wrote a comprehensive analysis of the farming system. Special attention was paid to the impact of the removal of all ruminants in 1986 (due to dramatic overgrazing and erosion) and the subsequent introduction of zero grazing in 1990. The economic, ecological and social impact of this dramatic government action was assessed (incl. assessing the nutrient balance in the area, with and without ‘destocking’). Despite some uncertainties (e.g. the impact on malaria), the conclusion was that ‘destocking’, as a way to replace extensive grazing systems with zero grazing is an option that deserve much more (positive) attention then it gets at present.
Next to describing the existing system, 13 potential innovations were screened on three aspects: ecological sustainability, economic viability and their impact on the position of women. The screening was based on several on-farm trials, participatory surveys and a lot of field-trials at the MRTC.
The final recommendations were: the introduction of zero grazing, new varieties of millet and sorghum and the promotion of sunflower were e ready for implementation. Intensive gardening, deep litter stables and better management of natural vegetation required further research. Biogas and chemical fertilizer could be appropriate, but their profitability depended much on prices of firewood and cereals. Both these technologies were actually disseminated by the MRTC. Mechanisation (with oxen), early harvesting of crop residues, alley cropping, compost and contour bunds proved to be inappropriate. The conclusion that agroforestry, compost and contour bunds were not appropriate lead to much discussion, but in all cases this was based on extensive fieldwork (e.g. a 4-year field trial with alley cropping and with fodder banks). The essential element was the very high labour costs for these technologies, and in case of alley cropping the risk involved in planting vigorous scrubs/trees in between food crops with which they are competing for water and light.
Holtland, G. 1994. A Farming System Analysis of Mvumi Division, Dodoma Region , Tanzania : A case study on intensifying agriculture in semi-arid Africa . MRTC Communication Bulletin, 1994. DCT, P.O. Box 2028 , Dodoma , Tanzania (133 p.). The paper is available from the DCT office in Dodoma as well as via CTRT.
