A 1990 macrolevel study that revealed declining soil fertility in Africa triggered microlevel case studies on nutrient flows. This report hypothesizes that a mesolevel approach can offer a valid entry point for policy-makers and private-sector intervention. The aim is to enable mesolevel stakeholders to better articulate and target scale-specific soil fertility enhancing measures.
The report synthesizes studies on soil nutrient stocks, flows and balances in order to calculate mesolevel balances for Ghana, Mali and Kenya. It explains nutrient flow calculations, shows how to construct mesolevel nutrient balances, discusses the differences between levels and between the three countries.
The mesolevel approach can consider specific management decisions and physiographic differences, and help target interventions on the basis of microlevel variations in nutrient management. In particular, it can identify constraints, use nutrient flows for planning purposes, and extrapolate results to other areas.
This report has been written for the FAO-commissioned project “Scaling soil nutrient balances”. The project started in January 2002 with a literature review and the collection of data. Three case-study countries were selected and cooperation started with national research institutes, namely: the Soil Research Institute and the Cocoa Research Institute of Ghana in Ghana, the Kenya Agriculture Research Institute in Kenya, and the Institut d’Economie Rurale in Mali. In February 2003, a two-day workshop in Nairobi discussed the preliminary results of the project.
