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Impacts of biofuel cultivation on mortality and crop yields


Ground-level ozone is a priority air pollutant, causing 22,000 excess deaths per year in Europe1, significant reductions in crop yields2 and loss of biodiversity3. It is produced in the troposphere through photochemical reactions involving oxides of nitrogen (NOx) and volatile organic compounds (VOCs). The biosphere is the main source of VOCs, with an estimated 1,150 TgC yr−1 ( 90% of total VOC emissions) released from vegetation globally4. Isoprene (2-methyl-1,3-butadiene) is the most significant biogenic VOC in terms of mass (around 500 TgC yr−1) and chemical reactivity4 and plays an important role in the mediation of ground-level ozone concentrations5. Concerns about climate change and energy security are driving an aggressive expansion of bioenergy crop production and many of these plant species emit more isoprene than the traditional crops they are replacing. Here we quantify the increases in isoprene emission rates caused by cultivation of 72 Mha of biofuel crops in Europe. We then estimate the resultant changes in ground-level ozone concentrations and the impacts on human mortality and crop yields that these could cause. Our study highlights the need to consider more than simple carbon budgets when considering the cultivation of biofuel feedstock crops for greenhouse-gas mitigation.

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Figure 1: Effect of replacing crops and grasses with high-emitting SRC species in our biofuel cultivation scenario.
Figure 2: Impact of increasing ground-level ozone concentrations on mortality.
Figure 3: Impact of increasing ground-level ozone concentrations on crop yield.


  1. Amann, M. et al. Baseline Scenarios for the Clean Air for Europe (CAFE) Programme Final Report 65–66 (Royal Society, 2005).

    Google Scholar 

  2. Fowler, D. et al. (Royal Society, 2008).

  3. Millennium Ecosystem Assessment Ecosystems and Human Well-being: Synthesis (Island, 2005).

  4. Guenther, A. B. et al. A global model of natural volatile organic compound emissions. J. Geophys. Res. 100, 8873–8892 (1995).

    Article  CAS  Google Scholar 

  5. Hewitt, C. N. et al. Ground-level ozone influenced by circadian control of isoprene emissions. Nature Geosci. 4, 671–674 (2011).

    Article  CAS  Google Scholar 

  6. Directive 2009/28/EC of the European Parliament and of the Council of 23 April 2009 on the Promotion of the Use of Energy from Renewable Sources and Amending and Subsequently Repealing Directives 2001/77/EC and 2003/30/EC (EC, 2008); available at (2008).

  7. Sustainable Biofuels: Prospects and Challenges Science Policy Report 01/08 (Royal Society, 2008).

  8. Guenther, A. et al. Estimates of global terrestrial isoprene emissions using MEGAN (Model of Emissions of Gases and Aerosols from Nature). Atmos. Chem. Phys. 6, 3181–3210 (2006).

    Article  CAS  Google Scholar 

  9. Wild, O. et al. Chemical transport model ozone simulations for spring 2001 over the western Pacific: Comparisons with TRACE-P lidar, ozonesondes, and Total Ozone Mapping Spectrometer columns. J. Geophys. Res. 108, D218826 (2003).

    Google Scholar 

  10. Oak Ridge National Laboratory. LandScan Global Population Database. Available at (2006).

  11. Monfreda, C., Ramankutty, N. & Foley, J. Farming the planet: 2. Geographic distribution of crop areas, yields, physiological types, and net primary production in the year 2000. Glob. Biogeochem. Cycles 22, GB1022 (2007).

    Google Scholar 

  12. Fischer, G. et al. Biofuel production potentials in Europe: Sustainable use of cultivated land and pastures, Part II: Land use scenarios. Biomass Bioenergy 34, 173–187 (2010).

    Article  Google Scholar 

  13. Hill, J. et al. Climate change and health costs of air emissions from biofuels and gasoline. Proc. Natl Acad. Sci. USA 106, 2077–2082 (2009).

    Article  CAS  Google Scholar 

  14. Fertiliser Use by Crop (FAO, 2006); available at

  15. Directive 2002/3/EC Relating to Ozone in Ambient Air (EC, 2002); available at

  16. Pattenden, S. et al. Ozone, heat and mortality: acute effects in 15 British conurbations. Occup. Environ. Med. 67, 699–707 (2010).

    Article  CAS  Google Scholar 

  17. Lindhjem, H., Navrud, S., Biausque, V. & Braathen, N. A. Mortality Risk Valuation in Environment, Health and Transport Policies (OECD, 2012); available at

  18. Pugh, T. A. M et al. A Lagrangian model of air-mass photochemistry and mixing using a trajectory ensemble: the Cambridge Tropospheric Trajectory model of Chemistry And Transport (CiTTyCAT) version 4.2. Geosci. Model Dev. 5, 193–221 (2012).

    Article  Google Scholar 

  19. Mills, G. et al. A synthesis of AOT40-based response functions and critical levels of ozone for agricultural and horticultural crops. Atmos. Environ. 41, 2630–2643 (2007).

    Article  CAS  Google Scholar 

  20. Avnery, S., Mauzerall, D. L., Liu, J. & Horowitz, L. W. Global crop yield reductions due to surface ozone exposure: 1. Year 2000 crop production losses and economic damage. Atmos. Environ. 45, 2284–2296 (2011).

    Article  CAS  Google Scholar 

  21. EC Eurostat. Agriculture database. Available at (2012).

  22. Fiore, A. M. et al. Multimodel estimates of intercontinental source- receptor relationships for ozone pollution. J. Geophys. Res. 114, D04301 (2009).

    Article  Google Scholar 

  23. Anenberg, S. C. et al. Intercontinental impacts of ozone pollution on human mortality. Environ. Sci. Technol. 43, 6482–6487 (2010).

    Article  Google Scholar 

  24. Andersson, C. & Engardt, M. European ozone in a future climate: Importance of changes in dry deposition and isoprene emissions. J. Geophys. Res. 115, D02303 (2010).

    Google Scholar 

  25. Air Quality Guidelines–Global Update 2005 (WHO, 2005).

  26. Eller, A. S. D. et al. Volatile organic compound emissions from switchgrass cultivars used as biofuel crops. Atmos. Environ. 45, 3333–3337 (2011).

    Article  CAS  Google Scholar 

  27. Behnke, K. et al. Isoprene emission-free poplars—a chance to reduce the impact from poplar plantations on the atmosphere. New Phytol. 194, 70–82 (2011).

    Article  Google Scholar 

  28. Archibald, A. T., Jenkin, M. E. & Shallcross, D. E. An isoprene mechanism intercomparison. Atmos. Environ. 44, 5356–5364 (2010).

    Article  CAS  Google Scholar 

  29. EMEP measurement data for ozone for 2001. Available at: (European Monitoring and Evaluation Programme, 2012).

  30. World Health Organization Mortality Database. Available at (WHO, 2005).

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This work was financially supported by a NERC studentship to K.A., through the Natural Environment Research Council QUEST-QUAAC project, grant number NE/C001621/1, and partially by Lancaster University.

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All authors devised the research, analysed the results and wrote the paper; K.A. conducted the model simulations.

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Correspondence to C. N. Hewitt.

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The authors declare no competing financial interests.

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Ashworth, K., Wild, O. & Hewitt, C. Impacts of biofuel cultivation on mortality and crop yields. Nature Clim Change 3, 492–496 (2013).

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