Local knowledge and the social shaping of soil investments: critical perspectives on the assessment of soil degradation in Africa.

This paper explores local knowledge and practices in soil management and investment that have frequently gone unrecognised in assessments of soil fertility transformations and trends. Case material drawn largely from the Guinea savannas of West Africa is used to challenge the assumptions and methods that agronomists have been using to assess soil fertility transformations and trends. It outlines the need for an approach to the study of soil fertility that engages more comparatively with local knowledge, and appreciates the social and moral orders which shape the ways both African farmers and western agronomists use and understand soils.