Slash-and-burn agroecosystems are important to rural poor and indigenous peoples in the developing world. Ecologically sound slash-and-burn agriculture is sustainable because it does not depend upon outside inputs based on fossil energy for fertilizers, pesticides and irrigation. One means of demonstrating the soundness of slash-and-burn agroecosystems is to prove empirically the ecological compatibility of this system of crop production. This paper examines the ecological sustainability of slash-and-burn agriculture based on the productivity of soil resources.