Armed conflicts often hinder food security through cropland abandonment and restrict the collection of on-the-ground information required for targeted relief distribution. Satellite remote sensing provides a means for gathering information about disruptions during armed conflicts and assessing the food security status in conflict zones. Using ~7,500 multisource satellite images, we implemented a data-driven approach that showed a reduction in cultivated croplands in war-ravaged South Sudan by 16% from 2016 to 2018. Propensity score matching revealed a statistical relationship between cropland abandonment and armed conflicts that contributed to drastic decreases in food supply. Our analysis shows that the abandoned croplands could have supported at least a quarter of the population in the southern states of South Sudan and demonstrates that remote sensing can play a crucial role in the assessment of cropland abandonment in food-insecure regions, thereby improving the basis for timely aid provision.
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The intermediate data that support the findings of this study are available at https://doi.org/10.17894/ucph.5e12bdda-b2d7-4835-8ae1-a7c49affb97b. Source data are provided with this paper. Land-cover training and validation data are available on request.
Code used for land-cover classification in GEE and propensity score analysis are available at https://github.com/victor-m-olsen/nature-food.
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We acknowledge the support of DFF-Danish ERC Support Program (grant number 116491, 9127-00001B). The funders had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript. We also acknowledge the WFP for providing in situ data for the study. Finally, we acknowledge the contribution of N. Keuler from the University of Wisconsin-Madison for consultation on statistical analysis.
The authors declare no competing interests.
Peer review information Nature Food thanks Manfred Buchroithner and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.
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Olsen, V.M., Fensholt, R., Olofsson, P. et al. The impact of conflict-driven cropland abandonment on food insecurity in South Sudan revealed using satellite remote sensing. Nat Food 2, 990–996 (2021). https://doi.org/10.1038/s43016-021-00417-3