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Options for keeping the food system within environmental limits

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The food system is a major driver of climate change, changes in land use, depletion of freshwater resources, and pollution of aquatic and terrestrial ecosystems through excessive nitrogen and phosphorus inputs. Here we show that between 2010 and 2050, as a result of expected changes in population and income levels, the environmental effects of the food system could increase by 50–90% in the absence of technological changes and dedicated mitigation measures, reaching levels that are beyond the planetary boundaries that define a safe operating space for humanity. We analyse several options for reducing the environmental effects of the food system, including dietary changes towards healthier, more plant-based diets, improvements in technologies and management, and reductions in food loss and waste. We find that no single measure is enough to keep these effects within all planetary boundaries simultaneously, and that a synergistic combination of measures will be needed to sufficiently mitigate the projected increase in environmental pressures.
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ARTICLE https://doi.org/10.1038/s41586-018-0594-0
Options for keeping the food system
within environmental limits
Marco Springmann1,2*, Michael Clark3, Daniel Mason-D’Croz4,5, Keith Wiebe4, Benjamin Leon Bodirsky6, Luis Lassaletta7,
Wim de Vries8, Sonja J. Vermeulen9,10, Mario Herrero5, Kimberly M. Carlson11, Malin Jonell12, Max Troell12,13,
Fabrice DeClerck14,15, Line J. Gordon12, Rami Zurayk16, Peter Scarborough2, Mike Rayner2, Brent Loken12,14, Jess Fanzo17,18,
H. Charles J. Godfray1,19, David Tilman20,21, Johan Rockström6,12 & Walter Willett22
The food system is a major driver of climate change, changes in land use, depletion of freshwater resources, and pollution
of aquatic and terrestrial ecosystems through excessive nitrogen and phosphorus inputs. Here we show that between
2010 and 2050, as a result of expected changes in population and income levels, the environmental effects of the food
system could increase by 50–90% in the absence of technological changes and dedicated mitigation measures, reaching
levels that are beyond the planetary boundaries that define a safe operating space for humanity. We analyse several
options for reducing the environmental effects of the food system, including dietary changes towards healthier, more
plant-based diets, improvements in technologies and management, and reductions in food loss and waste. We find that
no single measure is enough to keep these effects within all planetary boundaries simultaneously, and that a synergistic
combination of measures will be needed to sufficiently mitigate the projected increase in environmental pressures.
The global food system is a major driver of climate change
1,2
, land-use
change and biodiversity loss3,4, depletion of freshwater resources5,6, and
pollution of aquatic and terrestrial ecosystems through nitrogen and
phosphorus run-off from fertilizer and manure application
7–9
. It has
contributed to the crossing of several of the proposed ‘planetary bound-
aries’ that attempt to define a safe operating space for humanity on a
stable Earth system1012, in particular those concerning climate change,
biosphere integrity, and biogeochemical flows related to nitrogen and
phosphorous cycles. If socioeconomic changes towards Western con-
sumption patterns continue, the environmental pressures of the food
system are likely to intensify1316, and humanity might soon approach
the planetary boundaries for global freshwater use, change in land use,
and ocean acidification
11,12,17
. Beyond those boundaries, ecosystems
could be at risk of being destabilized and losing the regulation functions
on which populations depend11,12.
Here we analyse the option space available for the food system to
reduce its environmental impacts and stay within the planetary bound-
aries related to food production. We build on existing analyses that
have advanced the planetary-boundary framework in terms of systemic
threats to large-scale ecosystems11,12,1820, discussed the role of agricul-
ture with respect to those pressures10,21, and analysed the impacts on
individual environmental domains
22,23
, including selected measures
to alleviate those impacts22–24. The planetary-boundary framework
is not without criticism, particularly because of the heterogeneity of
the different boundaries and their underlying scientific bases, includ-
ing the difficulty of defining global ecosystem thresholds for local
environmental impacts2527. Despite these limitations, we consider
the planetary-boundary framework to be useful for framing, in broad
terms, the planetary option space that preserves the sustainability of
key ecosystems. We acknowledge the ongoing debate by quantifying the
planetary boundaries of the food system in terms of broad ranges that
reflect methodological uncertainties (seeMethods), and by reporting
the environmental impacts in absolute terms (for example, emissions
in tonnes of carbon dioxide equivalents), which allows for comparisons
to other measures of environmental sustainability.
We advance the present state of knowledge by constructing and
calibrating a global food-systems model with country-level detail that
resolves the major food-related environmental impacts and includes
a comprehensive treatment of measures for reducing these impacts
(seeMethods). The regional detailof the model accounts for different
production methods and environmental impacts that are linked by
imports and exports of primary, intermediate and final products. We
use the food-system model and estimates of present and future food
demand to quantify food-related environmental impacts at the countr y
and crop level in 2010 and 2050 for five environmental domains and the
related planetary boundaries: greenhouse-gas (GHG) emission related
to climate change; cropland use related to land-system change; fresh-
water use of surface and groundwater; and nitrogen and phosphorus
application related to biogeochemical flows.
To characterize pathways towards a food system with lower envi-
ronmental impacts that stays within planetary boundaries, we connect
a region-specific analysis of the food system to a detailed analysis of
1Oxford Martin Programme on the Future of Food, Oxford Martin School, University of Oxford, Oxford, UK. 2Centre on Population Approaches for Non-Communicable Disease Prevention, Nuffield
Department of Population Health, University of Oxford, Oxford, UK. 3Natural Resources Science and Management, University of Minnesota, St Paul, MN, USA. 4Environment and Production
Technology Division, International Food Policy Research Institute (IFPRI), Washington, DC, USA. 5CSIRO Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation,
St Lucia, Brisbane, Australia. 6Potsdam Institute for Climate Impact Research, Potsdam, Germany. 7CEIGRAM/Agricultural Production, Universidad Politécnica de Madrid, Madrid, Spain.
8Environmental Systems Analysis Group, Wageningen University, Wageningen, The Netherlands. 9WWF International, Gland, Switzerland. 10Hoffmann Centre for Sustainable Resource Economy,
Chatham House, London, UK. 11Department of Natural Resources and Environmental Management, University of Hawai’i at Manoa, Honolulu, HI, USA. 12Stockholm Resilience Centre, Stockholm
University, Stockholm, Sweden. 13Beijer Institute of Ecological Economics, The Royal Swedish Academy of Sciences, Stockholm, Sweden. 14EAT, Oslo, Norway. 15Agricultural Biodiversity and
Ecosystem Services, Bioversity International, Rome, Italy. 16Department of Landscape Design and Ecosystem Management, Faculty of Agricultural and Food Sciences, American University of Beirut,
Beirut, Lebanon. 17Nitze School of Advanced International Studies (SAIS), Berman Institute of Bioethics, Johns Hopkins University, Baltimore, MD, USA. 18Department of International Health of the
Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA. 19Department of Zoology, University of Oxford, Oxford, UK. 20Department of Ecology, Evolution and Behavior,
University of Minnesota, St Paul, MN, USA. 21Bren School of Environmental Science and Management, University of California, Santa Barbara, CA, USA. 22Department of Epidemiology and
Department of Nutrition, Harvard T. H. Chan School of Public Health, Boston, MA, USA. *e-mail: marco.springmann@dph.ox.ac.uk
25 OCTOBER 2018 | VOL 562 | NATURE | 519
© 2018 Springer Nature Limited. All rights reserved.
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Tens of thousands of species are threatened with extinction as a result of human activities. Here we explore how the extinction risks of terrestrial mammals and birds might change in the next 50 years. Future population growth and economic development are forecasted to impose unprecedented levels of extinction risk on many more species worldwide, especially the large mammals of tropical Africa, Asia and South America. Yet these threats are not inevitable. Proactive international efforts to increase crop yields, minimize land clearing and habitat fragmentation, and protect natural lands could increase food security in developing nations and preserve much of Earth's remaining biodiversity. © 2017 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.
Technical Report
This report provides a quantitative assessment of the impacts of alternative investment options on the CGIAR’s SLOs (relating to poverty – SLO1, food and nutrition security – SLO2, and natural resources and ecosystem services – SLO3) in the context of changes in population, income, technology, and climate to 2050 as well as for key SDGs of importance to the developing world. The report serves as a source of information and evidence of the impact of CGIAR efforts in agricultural R&D as well as the role of complementary investments. It is intended to help the CGIAR Centers, CG Research Programs (CRP), system management, and donors to complement other efforts to assess the overall impact and benefits of investing in international and national agricultural research programs. Available online at: http://ebrary.ifpri.org/cdm/ref/collection/p15738coll2/id/131144