Advancing human nutrition without degrading land resources through modeling cropping systems in Ethiopian highlands

Abstract

Food shortage in Sub-Saharan Africa is predominantly taken as a function of limited access to food, without considering nutritional quality. Analyzing households’ production of nutrients on farm across farming systems could be valuable in guiding intensification of those systems. An optimization model was employed to analyze the scenario of human nutrition and cropland allocation in Enset (Enset ventricosum)/root crop – based (Areka) or cereal-based (Ginchi) systems of Ethiopian highlands. The type and amount of nutrients produced in each system was analyzed and an optimization model was used to analyse, which cropping strategies may improve the nutritional quality of the household using the existing resources. Both production systems were in food deficit, in terms of quantity and quality, except for iron. Energy supply of resource-poor households in the enset/root crop-based system was only 75% of Recommended Daily Allowance (RDA), while resource-rich farmers covered their energy, protein, zinc, and thiamine demand. Extremely high deficiency was found in zinc, calcium, Vit A and Vit C, which was only 26.5, 34, 1.78 and 12 % of the RDA, respectively. The RDA could be satisfied if they expand the land area of enset, kale and beans by about 20, 10 and 40 %, respectively, at the expense of maize and sweet potato. The critical deficit of the cereal-based system was also calcium, Vit A, and Vit C, which was only 30, 2.5 and 2% of the RDA. In the cereal system, the RDA could be fully satisfied by reducing crop land allocated for barley by about 50% and expand the land area of faba beans, kale and enset. However, Ginchi farmers have better copying options than Areka farmers as they own more land and higher number of livestock that could be used as buffering assets. A shift from the cereal/root crop dominated system to a perennial-enset dominated system would decrease soil erosion by improving the crop factor by about 45 %. It also has a very strong positive implication for soil fertility management. However, any policy suggestion for change in cropland allocation should be done through bottom-up negotiations with households, communities and district stakeholders