Soil fertility management strategies on the Jos Plateau: the need for integrating 'empirical' and 'scientific' knowledge in agricultural development

Tin mining carried out on the Jos Plateau since the beginning of the last century has disturbed some 320 km² of agricultural land. Formal attempts at reclamation of this land failed, but local farmers have developed a successful informal strategy for reclamation. This paper reports on a study undertaken to comprehend the farmers'informal' approach to soil fertility management. Their soil fertility management practices centre on the use of a complex combination of traditional organic manures and 'modern' inorganic fertilizers that they have developed entirely on the basis of experimentation. A central focus of this paper is therefore the empirical knowledge base of the farmers and an assessment of any underlying scientific explanations for their strategies, including an analysis of their assertion that different brands of NPK fertilizers differ in their nutrient value. This discussion is followed by a consideration of the difficulties in accessing and understanding empirical knowledge. It is concluded that farmers' knowledge and understanding of the values of different fertilizers and manures does have a scientific basis. It is argued that for further agricultural development to take place on the Jos Plateau, there must be synergy between farmers' empirical knowledge (which has led to the development of successful and effective soil fertility management strategies, unlike the attempts of the local 'scientific' communities) and scientific knowledge (which can identify health and environmental hazards which may not be immediately visible to farmers).