Profitable and Sustainable Nutrient Management Systems for Sub-Saharan African Smallholder Farming Systems.

Population growth and dietary change is projected to drive global food demand to unprecedented levels. To keep pace, by 2050 food production will have to increase by 70 %. This can only be achieved through sustainable agricultural intensification, which is still one of the major issues to be addressed in sub-Saharan Africa (SSA). Chemical fertilizer application in SSA has been chronically low, with present average consumption of nitrogen, phosphate and potassium less than 9 kg/ha/yr. This is largely due to the inability of SSA smallholders to (physically and financially) access agricultural input and output markets. As a consequence, soils have been depleted and degraded at large scale and alarming rate across the sub-continent.

It has been argued that “in the short term, chemical fertilizers are the best way to feed Africa”. However, agronomists and agro-economists tend to agree that fertilizers alone will not solve SSA farmers' problems in the medium to long-term. A sound management of soil health is required, which considers a balanced use of nutrients, integrates the physical and biological fertility of the soil and thus increases the agricultural eco-efficiency. In SSA this can only be realized in a stepping stone approach that reduces nutrient input constraints, increases biomass production and soil organic matter levels in a step-wise fashion, as farmers increase investments over time, driven by sustainable profitability, output market linkages, and eco-efficiency of the farming systems.

We present and discuss sustainable, resilient and profitable nutrient management systems that embrace the principals of integrated soil fertility management and conservation agriculture. The issue of farmers' market access is addressed by a bottom-up approach via formation of innovation platforms (IPs). IP is a forum established among stakeholders along a commodity value chain to facilitate interactions, learning, problem diagnosis, joint exploration and investment in solutions. Such nutrient management systems can increase food and security without jeopardizing environmental quality.