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The impact of conflict-driven cropland abandonment on food insecurity in South Sudan revealed using satellite remote sensing

Nature Food volume 2, pages 990–996 (2021)Cite this article

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An Author Correction to this article was published on 11 January 2022

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Abstract

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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Fig. 1: Land-cover maps.
Fig. 2: Missed crop production per crop type.

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Data availability

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 availability

Code used for land-cover classification in GEE and propensity score analysis are available at https://github.com/victor-m-olsen/nature-food.

Change history

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Acknowledgements

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.

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Authors and Affiliations

  1. Department of Geosciences and Natural Resource Management (IGN), University of Copenhagen, København, Denmark

    Victor Mackenhauer Olsen, Rasmus Fensholt & Alexander V. Prishchepov

  2. Department of Earth and Environment, Boston University, Boston, MA, USA

    Pontus Olofsson

  3. Vulnerability Analysis and Mapping (VAM), United Nations World Food Programme (WFP), Rome, Italy

    Rogerio Bonifacio

  4. Department of Environmental Science, Policy & Management, University of California, Berkeley, CA, USA

    Van Butsic

  5. DHI GRAS, Hørsholm, Denmark

    Daniel Druce

  6. Institute on the Environment (IonE), University of Minnesota, St. Paul, MN, USA

    Deepak Ray

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Contributions

V.O. conducted all analyses in this research and drafted the paper. A.P. and R.F. supervised the work, revised the paper and provided technical and thematic insights. Additionally, A.P. conducted the analysis on kilocalorie availability. P.O. and D.D. contributed to the accuracy assessment. R.B. provided field data and revised the paper. V.B. supervised the econometric analysis. D.R. contributed to the food security narrative. All authors edited, reviewed and approved the final manuscript.

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Correspondence to Victor Mackenhauer Olsen.

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The authors declare no competing interests.

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Peer review information Nature Food thanks Manfred Buchroithner and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1 and 2 and Tables 1–17.

Source data

Source Data Fig. 2

Calculation on missed crop production and kilocalories.

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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

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