Forecasting Agriculturally Driven Global Environmental Change
Abstract
During the next 50 years, which is likely to be the final period of rapid agricultural expansion, demand for food by a wealthier and 50% larger global population will be a major driver of global environmental change. Should past dependences of the global environmental impacts of agriculture on human population and consumption continue, 109 hectares of natural ecosystems would be converted to agriculture by 2050. This would be accompanied by 2.4- to 2.7-fold increases in nitrogen- and phosphorus-driven eutrophication of terrestrial, freshwater, and near-shore marine ecosystems, and comparable increases in pesticide use. This eutrophication and habitat destruction would cause unprecedented ecosystem simplification, loss of ecosystem services, and species extinctions. Significant scientific advances and regulatory, technological, and policy changes are needed to control the environmental impacts of agricultural expansion.
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REFERENCES AND NOTES
1
G. Conway, The Doubly Green Revolution (Penguin Books, London, 1997).
2
Vitousek P. M., Mooney H. A., Lubchenco J., Melillo J. M., Science 277, 494 (1997).
3
Carpenter S. R., et al., Ecol. Appl. 8, 559 (1998).
4
Schindler D. W., Ambio 28, 350 (1999).
5
Tilman D., Proc. Natl. Acad. Sci. U.S.A. 96, 5995 (1999).
6
Matson P. A., Parton W. J., Power A. G., Swift M. J., Science 277, 504 (1997).
7
Matson P. A., McDowell W., Townsend A., Vitousek P., Biogeochemistry 46, 67 (1999).
8
National Research Council, Global Change Ecosystems Research (National Academy Press, Washington, DC, 2000).
9
Postel S. L., Daily G. C., Ehrlich P. R., Science 271, 785 (1996).
10
Pimm S. L., Russell G. J., Gittleman J. L., Brooks T. M., Science 269, 347 (1995).
11
J. E. Cohen, How Many People Can the Earth Support? (Norton, New York, 1995).
12
World Population Prospects: The 1998 Revision, vol. I, Comprehensive Tables (UN Department of Economic and Social Affairs, Population Division, New York, 1999).
13
A. Maddison, Monitoring the World Economy 1820–1992 (Development Center of the Organization for Economic Cooperation and Development, Paris, 1995). GDP was extended to 1998 using annual percent increases in (17).
14
National Research Council, Our Common Journey: A Transition Toward Sustainability (National Academy Press, Washington, DC, 1999).
15
Reference (14) forecasts constant-dollar global GDP growth of 2.7% year−1 from 1995 to 2050. We used a more conservative 2.5% based on analysis of the 40-year trend (13) in the annual rate of growth of constant-dollar global per capita GDP.
16
J. T. Houghton et al., Climate Change 1995: The Science of Climate Change (Cambridge Univ. Press, Cambridge, 1996).
17
World Development Indicators, CD-ROM (World Bank, Washington, DC, 2000)
18
Food and Agriculture Organization of the United Nations, FAOSTAT homepage [on-line] (2001). Available at:. Cropland refers to the FAO land-use category of “arable and permanent crops.” Pasture is FAO's “permanent pasture.”
19
Fertilizer projections are for the entire world except the former USSR, whose economic problems added variance to the relationship.
20
If the former USSR is included, the 2050 global fertilizer projection for N is 270 × 106 MT year−1 and for P is 110 × 106 MT year−1. If N fixation by combustion of fossil fuels and by crops doubled by 2050, these plus N fertilization (including the USSR) would add 390 × 106 MT year−1, 2.8 times more N than all natural processes combined.
21
S. L. Postel, Pillar of Sand: Can the Irrigation Miracle Last? (Norton, New York, 1999).
22
Alexandratos N., Proc. Natl. Acad. Sci. U.S.A. 96, 5908 (1999).
23
National Research Council, Clean Coastal Waters: Understanding and Reducing the Effects of Nutrient Pollution (National Academy Press, Washington, DC, 2000).
24
Bouwman A. F., et al., Global Biogeochem. Cycles 11, 561 (1997).
25
Howarth R. W., et al., Biogeochemistry 35, 75 (1996).
26
Holland E. A., Dentener F., Braswell B., Sulzman J., Biogeochemistry 46, 7 (1999).
27
Naylor R. L., et al., Nature 405, 1017 (2000).
28
J. A. Downing et al., Gulf of Mexico Hypoxia: Land and Sea Interactions (Task Force Report No. 134, Council for Agricultural Science and Technology, Ames, IA, 1999).
29
Assessment Report: Arctic Pollution Issues (Arctic Monitoring and Assessment Program, Oslo, Norway, 1998).
30
World Health Organization, Public Health Impacts of Pesticides Used in Agriculture (WHO & UN Environment Program, Geneva, 1990).
31
Kidd K. A., Schindler D. W., Muir D. C. G., Lockhart W. L., Hesslein R. H., Science 269, 240 (1995).
32
N. Alexandratos, World Agriculture: Toward 2010 (Wiley, Chichester, UK, 1995).
33
W. H. Schlesinger, Biogeochemistry: An Analysis of Global Change (Academic Press, San Diego, CA, 1997).
34
Sala O. E., et al., Science 287, 1770 (2000).
35
Cassman K. G., Proc. Natl. Acad. Sci. U.S.A. 96, 5952 (1999).
36
Ruttan V. W., Proc. Natl. Acad. Sci. U.S.A. 96, 5960 (1999).
37
G. C. Daily, Nature's Services: Societal Dependence on Natural Ecosystems (Island Press, Washington, DC, 1997).
38
Daily G. C., et al., Science 289, 395 (2000).
39
J. Walsh, Preserving the Options: Food Production and Sustainability (CGIAR, Washington, DC, 1991).
40
Zhu Y., et al., Nature 406, 718 (2000).
41
P. L. Woomer, M. J. Swift, Eds., The Biological Management of Tropical Soil Fertility (Wiley, Chichester, UK, 1994).
42
M. J. B. Green, J. Paine, State of the World's Protected Areas at the End of the Twentieth Century, IUCN (The Conservation Union) Protected Areas Symposium, Albany, Western Australia, 23 to 29 November 1997 (World Council on Protected Areas, Gland, Switzerland, 1998). Available at www.wcmc.org.uk/protected_areas/albany.pdf
43
Janzen D., Proc. Natl. Acad. Sci. U.S.A. 96, 5987 (1999).
44
Groot J., Penning J. R., De Vries F. W. T., Uithol P. W. J., Nutr. Cycl. Agroecosys. 50, 181 (1998).
45
We thank the National Center for Ecological Analysis and Synthesis for support; N. Larson and L. Johnson for assistance; R. Cook for advice on statistical methods; and V. Ruttan, S. Hobbie, S. Polasky, J. Reichman, G. Daily, D. Wilcove, J. Lubchenco, D. Janzen, J. Clark, J. Cohen, S. Carpenter, P. Vitousek, and E. Sandlin for comments.
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Science
Volume 292 | Issue 5515
13 April 2001
13 April 2001
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Received: 22 January 2001
Accepted: 8 March 2001
Published in print: 13 April 2001
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