The dynamics of soil fertility change: historical perspectives on environmental transformation from Zimbabwe

Soil fertility is currently highlighted as a major issue for African agricultural development. But embedded within policy statements are a series of underlying assumptions and methodological commitments. This paper questions these, arguing that an historical approach to understanding the dynamics of soil fertility change offers important insights of relevance to development policy and planning. Work on environmental change in southern Zimbabwe emphasizes how issues of non-linear dynamics, spatial heterogeneity and the role of contingent events in precipitating change are important in understanding the nature of soils and their management. Transformation of soils is seen to be the result of a complex interaction of factors, mediated by a variety of social, economic and political institutions over time. Such insights suggest a more embedded, context-specific, adaptive and learning approach to intervention, which rejects simplistic, aggregated assessments of people-resource relationships, but instead takes uncertainty, complexity and the potential for non-linear change seriously.