Food insecurity is rising across sub-Saharan Africa (SSA), where undernourishment continues to affect a large portion of the population, particularly young children. Studies examining the associations between crop diversity and childhood nutrition have recently proliferated but are characterized by inconsistent results and two key limitations. First, many studies focus only on the household level, overlooking the prospect that more diverse crops at village and regional levels may contribute to household food security. Second, many studies pool data from multiple countries, which may obscure important context-specific aspects of nutrition outcomes. Drawing on Demographic and Health Survey (DHS) data from 10 SSA countries, in combination with agricultural production estimates for 112 crop species, this study explores the associations between crop diversity at multiple scales (10-, 25-, and 50-kilometer radii) and children’s dietary diversity (HDDS). In addition to producing overall estimates across our sample, we measure country-specific associations to account for spatial heterogeneity. Results of the overall model show a negative association between crop diversity and dietary diversity. However, the country-specific analyses uncover extensive variability in these associations: in some cases, diversity is highly positively correlated with HDDS, while in others the estimated effect is negative or nonexistent. Our findings suggest that country-level analyses provide important nuance that may be masked in pooled analyses. Moreover, these findings foreground the importance of looking beyond household-level analyses to understand the dynamic role that local crop diversity, and its exchange across space, can play in supporting children’s dietary diversity.
Foreign investors have acquired approximately 90 million hectares of land for agriculture over the past two decades. The effects of these investments on local food security remain unknown. While additional cropland and intensified agriculture could potentially increase crop production, preferential targeting of prime agricultural land and transitions toward export-bound crops might affect local access to nutritious foods. We test these hypotheses in a global systematic analysis of the food security implications of existing land concessions. We combine agricultural, remote sensing, and household survey data (available in 11 sub-Saharan African countries) with georeferenced information on 160 land acquisitions in 39 countries. We find that the intended changes in cultivated crop types generally imply transitions toward energy-rich, but nutrient-poor, crops that are predominantly destined for export markets. Specific impacts on food production and access vary substantially across regions. Deals likely have little effect on food security in eastern Europe and Latin America, where they predominantly occur within agricultural areas with current export-oriented crops, and where agriculture would have both expanded and intensified regardless of the land deals. This contrasts with Asia and sub-Saharan Africa, where deals are associated with both an expansion and intensification (in Asia) of crop production. Deals in these regions also shift production away from local staples and coincide with a gradually decreasing dietary diversity among the surveyed households in sub-Saharan Africa. Together, these findings point to a paradox, where land deals can simultaneously increase crop production and threaten local food security.
more » « less- Award ID(s):
- 1824951
- PAR ID:
- 10210550
- Publisher / Repository:
- Proceedings of the National Academy of Sciences
- Date Published:
- Journal Name:
- Proceedings of the National Academy of Sciences
- Volume:
- 118
- Issue:
- 4
- ISSN:
- 0027-8424
- Page Range / eLocation ID:
- Article No. e2020535118
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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