Protecting half of the planet could directly affect over one billion people

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In light of continuing global biodiversity loss, one ambitious proposal has gained considerable traction amongst conservationists: the goal to protect half the Earth. Our analysis suggests that at least one billion people live in places that would be protected if the Half Earth proposal were implemented within all ecoregions. Taking into account the social and economic impacts of such proposals is central to addressing social and environmental justice concerns, and assessing their acceptability and feasibility.

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Fig. 1: Additional areas to be protected to meet Half Earth 50% protection targets within each ecoregion.

Data availability

The datasets used in this study are all publically available or available to educational institutions for non-commercial purposes, but not distributable by the authors. Details of each dataset and download links are provided in the Supplementary Information.

Code availability

The R code used to reproduce the results is provided in the Supplementary Information.


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J.G.Z. undertook this work while a Visiting Scholar in the Department of Geography, University of Cambridge (May 2018–April 2019), and was supported by the Swiss Programme for Research on Global Issues for Development (r4d programme), which is funded by the Swiss National Science Foundation and the Swiss Agency for Development and Cooperation (grant no. 400440 152167). Our analysis was conducted utilizing the LandScan (2017) high resolution global population data set copyrighted by UT-Battelle, LLC, operator of Oak Ridge National Laboratory under Contract No. DE-AC05-00OR22725 with the United States Department of Energy.

Author information

J.S., J.G.Z., C.F., B.V., P.V. and C.S. designed the analyses. J.S. and J.G.Z. compiled the data and conducted the analyses. J.S. wrote the paper with input from J.G.Z., C.F., B.V., P.V. and C.S.

Correspondence to Judith Schleicher.

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The authors declare no competing interests.

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Supplementary information

Supplementary information

Supplementary Figs. 1–3, methods, notes and references.

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Schleicher, J., Zaehringer, J.G., Fastré, C. et al. Protecting half of the planet could directly affect over one billion people. Nat Sustain 2, 1094–1096 (2019) doi:10.1038/s41893-019-0423-y

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