Book of Abstracts
11th IFOAM Scientific Conference
11-15 August 1996, Copenhagen, Denmark
1Institute of Biomass Utilization and Biorefinery, South Jutland University Centre (SUC), Niels Bohrs Vej 9, DK-6700 Esbjerg, Denmark. 2Radio Rurale, 03 BP7029, Ouagadougou, Burkina Faso.
Consequences of the zai system for soil, yield, natural resources and living standards. Evaluation of the farmers knowledge.
Zai technique is an ancient, indigenous method of cultivation, used by farmers in periods of drought. During the last 15-20 years, farmers have successfully improved the system, which includes three essential phases: 1) digging holes, 20-25.000/ha, diameter 20-30 cm and depth 15-20 cm 2) filling holes with compost 3) planting seeds: Sorghum sp, millet, (Pennisetum typhoides), and cowpea, (Vigna unguiculata). The holes are usable for three years. Methods: Investigations Oct-Nov 1995. 1) Field analyses: Soil sieving tests, plants, holes 2) Thorough interviews with peasants from four villages: Gourga, Saye, Somiaga, Kao.
Results: Soil: Aggregate size as weighed average diameter (WAD) was used as a measure of soil fertility. Results indicate, that WAD is significant higher in fields with zai technique (0.46 mm) compared to fields without (0.34 mm). More investigations are needed.
Farmers' experience: The yield is at least the double, when using the zai technique, the plants are higher. The compost is made from farmyard manure, plant residues, garbage and burkina-phosphate, a natural product from mines in Burkina. This procedure implicates a new type of domestic animal management, changing of an extensive agriculture into intensification and integration of animal husbandry in agriculture. Trees sprout spontaneously in the zai holes, an example is a field of three ha with nine trees changing to 1400 trees without any planting work. The field is becoming a green savannah, cultivation continues between the trees or in a new area. The living standards are improved remarkably, when the food supply is sufficient. The farmers are organizing groups, acquainting each other with the zai technique, several organisations have formed. The barriers of propagation are simple: Lack of know-ledge, training, donkey carts for carrying compost, barrows, tools, domestic animals, infrastructure.
Mortimore, M. (1995): Caring for the soil. Agricultural Expansion, Population Growth and Natural Resource Degradation in Sahel. SEREIN. Occ. paper. No.1.
Ouedraogo, A. (1990): Resultats socio-economiques de la Methode traditionelle de Zai au Niveau des Exploitants agrico-les du Burkina Faso. Communications a la 8me Conference IFOAM in Budapest. Paper.
Pieri, C. (1989): Fertilites des Terres de Savannes. Ministere de la Cooperation et CIRAD-IRAT. (In english 1992, Springer Verlag).