SORGHUM CULTIVATION AND SOIL FERTILITY PRESERVATION UNDER Bujimi SLASH-AND-BURN CULTIVATION IN NORTHWESTERN ZAMBIA

Abstract

Here, we describe the cropping system of bujimi slash-and-burn cultivation by the Kaonde people in northwestern Zambia. Bujimi cultivation comprises three cropping systems: monde, making ash patches; milala, making mounds; and masengele, making flat fields. The three cropping systems accumulate soil fertility in different manners, and soil fertility dynamics vary after cultivation. Sorghum was sown for three or four consecutive years, usually followed by maize cultivation for additional 3 or 4 years. After clearing closed forest, the Kaonde gradually expanded small plots of the three cropping systems in the newly generated grassland adjacent to the cultivated field each year, thus creating new soil in bujimi fields for three or four successive years. As a result, varied soil fertility was created in mosaic patterns by combining the cropping systems with the number of cultivation years. The Kaonde also observed the grass species and grass biomass in crop fields and used them as indicators of soil fertility. When they noticed a decline in soil fertility, they planted sweet potato and cassava instead of sorghum monoculture. The Kaonde people maintain sustainable food production through multifold soil fertility preservation and mixed cropping.