Nutritional functional trait diversity of crops in south-eastern Senegal.
Ecological trait diversity metrics have been used to highlight the impacts of agriculture. Such metrics can also be used to include human nutrition-an important dimension of human well-being-into assessments of agroecosystem function and services. Although crop yield is a common agroecosystem metric, it does not capture the multiple ways in which agriculture impacts people and the environment. Given that nutrient composition of crops is a set of functional traits, I apply a suite of functional diversity metrics-functional divergence, richness, evenness and dispersion-to crop production data from south-eastern Senegal. I also propose a new nutritional diversity metric-potential nutrient adequacy-to assess nutritional outcomes of different agricultural systems. I demonstrate high variability in nutritional diversity and potential adequacy among households and administrative departments in south-eastern Senegal. I show that most households produce nutritionally similar crops, rather than crops with high nutritional diversity. As a result, most households currently do not produce enough nutrients to meet minimal nutritional requirements. Using a scenario approach, I show that intensifying yields of staple crops and diversifying production to include non-staples can increase nutritional production and the potential to meet nutritional needs. I further show that a combination of intensification and diversification is needed to meet the need for a diverse group of nutrients. Policy implications. I develop a new metric that indicates the potential for a food system to meet the nutritional requirements of a population. This tool will allow practitioners to assess the nutritional adequacy of a food system and to design food systems that optimize nutritional outcomes. Application of this metric to different production scenarios showed that combining yield intensification with crop diversification is important to meeting full nutritional targets for smallholder agriculture. There is a broader need for incorporating other social and socio-ecological traits into trait-based assessments of agroecosystems.