Isabel Lambrecht

Assessing Nutritional Diversity of Cropping Systems in African Villages

Background In Sub-Saharan Africa, 40% of children under five years in age are chronically undernourished. As new investments and attention galvanize action on African agriculture to reduce hunger, there is an urgent need for metrics that monitor agricultural progress beyond calories produced per capita and address nutritional diversity essential for human health. In this study we demonstrate how an ecological tool, functional diversity (FD), has potential to address this need and provide new insights on nutritional diversity of cropping systems in rural Africa. Methods and Findings Data on edible plant species diversity, food security and diet diversity were collected for 170 farms in three rural settings in Sub-Saharan Africa. Nutritional FD metrics were calculated based on farm species composition and species nutritional composition. Iron and vitamin A deficiency were determined from blood samples of 90 adult women. Nutritional FD metrics summarized the diversity of nutrients provided by the farm and showed variability between farms and villages. Regression of nutritional FD against species richness and expected FD enabled identification of key species that add nutrient diversity to the system and assessed the degree of redundancy for nutrient traits. Nutritional FD analysis demonstrated that depending on the original composition of species on farm or village, adding or removing individual species can have radically different outcomes for nutritional diversity. While correlations between nutritional FD, food and nutrition indicators were not significant at household level, associations between these variables were observed at village level. Conclusion This study provides novel metrics to address nutritional diversity in farming systems and examples of how these metrics can help guide agricultural interventions towards adequate nutrient diversity. New hypotheses on the link between agro-diversity, food security and human nutrition are generated and strategies for future research are suggested calling for integration of agriculture, ecology, nutrition, and socio-economics.

Integrated soil fertility management: from concept to practice in Eastern DR Congo

Many paradigms on sustainable agricultural intensification promote a combination of different agricultural technologies. Whether such a paradigm survives in practice depends on how farmers combine these technologies on their fields. We focus on integrated soil fertility management (ISFM) and investigate how the concept is put into practice in South-Kivu, Eastern DR Congo. ISFM includes the use of improved germplasm, organic inputs and mineral fertilizer, and emphasizes the complementarities and synergies that arise when technologies are jointly applied. We investigate whether different ISFM components are applied jointly, sequentially or independently, and whether that matters for the long-term use of the technology. We use original survey data from 420 farms, and combine a descriptive statistical analysis and a factor analysis. We find that few farmers in the area have reached ‘full ISFM’, and technology application occurs sequentially rather than simultaneously. Two technology subsets can be distinguished: more resource-intensive and less resource-intensive technologies. These subsets behave as supplements rather than as complements, and adoption within and among each subset is more sequential than simultaneous. Our results imply that there is a disconnect between the theoretical arguments in the agronomic ISFM literature, and the actual patterns of ISFM application on farmers’ fields.

Smallholders and land tenure in Ghana: Aligning context, empirics, and policy

For decades, policymakers and development practitioners have debated benefits and threats of property rights formalization and private versus customary tenure systems. This paper provides insights into the challenges in understanding and empirically analyzing the relationship between tenure systems and agricultural investment, and formulates policy advice that can support land tenure interventions. We focus on Ghana, based on extensive qualitative fieldwork and a review of empirical research and policy documents. Comparing research findings is challenging due to the use of different indicators, the varying contexts, and the diversity of investments. The interaction between land rights and investment make establishing causality extremely difficult. Setting policy priorities and strategies requires more and better insights into the diverse responses of different stakeholders and the tenure and cropping systems involved.