Msimu wa Kupanda : targeting resources within diverse, heterogenous and dynamic farming systems of East Africa.

Soil fertility decline is the major single factor explaining the decrease in per capita food production in sub-Saharan Africa. Integrated soil fertility management (ISFM) is an approach to improving or restoring soil productivity, based on combinations of organic and mineral fertilisers, improved germplasm and N2-fixation, but its adoption by farmers has been limited. Smallholder farms in sub-Saharan Africa are highly diverse, heterogeneous and dynamic, and operate in complex socio-ecological environments. Much of the heterogeneity within the farming systems is caused by spatial soil variability. This affects the performance of ISFM technologies, which must be then targeted strategically within heterogeneous farming systems to ensure their propensity to enhance the efficiency of resource (e.g. land, labour, nutrients) use at farm scale. An analytical framework in which systems analysis is aided by survey, experiments and simulation modelling was used to analyse farming futures in the highlands of East Africa. Case study farms from six moderate to high potential agricultural areas in central and western Kenya and eastern Uganda were characterised to identify the diversity of livelihood strategies and understand the main drivers of farm heterogeneity. Constraints to the performance of ISFM technologies and opportunities for efficient targeting of resources within heterogeneous smallholder farms were analysed considering short and long-term horizons, scaling up from field to farm scale, and contextualising livelihood opportunities at regional scale...