Influence of the Caiçaras on Soil Properties in the Savanna Region of Roraima, Northern Amazon

Abstract

The management of caiçaras by indigenous peoples in the “Lavrado” (savannas) region of Roraima is a practice that increases soil fertility. Caiçaras are temporary corrals where farmers keep the cattle at night for a certain period, when the soil is enriched by manure addition. In periods when these areas are not used as corrals, they may be planted with different plants species. In addition, areas adjacent to caiçaras may receive manure runoff and also be used for crop production. The study evaluated the changes in soil physical and chemical characteristics resulting from manure supply and runoff in caiçara and adjacent areas and compared these to soil characteristics of nearby unmanaged areas. Soil samples from the three system components were analyzed. The nutrient content added by manure runoff in the plantation adjacent to the caiçara resulted in significant accumulations of organic Ca, Mg, K, P, C, and micronutrients in the soil, without, however, changing pH. Only the soil surface (0–5 cm) showed improvements in soil bulk density and total porosity. This soil management system proves how efficient indigenous farmers can be in integrating their livestock component with the exploitation of available resources to improve soil fertility in areas of low natural fertility, enhancing agricultural production.