Human Impacts on the Nitrogen Cycle

NOV 01, 1994

Fertilizer production ond other human activities have more than doubled the global rate of nitrogen fixation since preindustrial times. The resulting imbalance is contributing to ecosystem disruption, ozone depletion, greenhouse effects and other environmental problems.

DOI: 10.1063/1.881423

Ann P. Kinzig

Robert H. Socolow

Humans are greatly perturbing the global nitrogen cycle. Perhaps the best evidence for this perturbation comes from air trapped in layers of quasipermanent ice in the Arctic and the Antarctic. Ice cores taken from these two polar regions give us a 2000‐year record of the Earth’s atmospheric composition. This record indicates a striking constancy in nitrous oxide concentrations, at approximately 285 parts per billion, for nearly 1500 years. (See figure 2.) Since about 1600 AD, however, nitrous oxide concentrations have been increasing, and the present‐day atmospheric burden of this gas is greater than at any other time in the past two millennia. Furthermore, nitrous oxide concentrations continue to increase, currently at a rate of about 0.3% per year. These variations indicate that many nitrogen flows are now larger than in preindustrial times, and other evidence suggests that human activity is responsible. (See figure 1.).

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References

1. Intergovernmental Panel on Climate Change, World Meteorological Organization and the United Nations Environment Programme, Climate Change: The IPCC Scientific Assessment, J. T. Houghton, G. J. Jenkins, J. J. Ephraums, eds., Cambridge U.P., Cambridge, England (1990).
2. T. Rosswall, in Some Perspectives of the Major Biogeochemical Cycles, G. E. Likens, ed., Wiley, New York (1981), p. 25.
3. M. G. Lawrence, W. L. Chameides, P. S. Kasibhatla, H. Levy II, W. Moxim, “Lightning and Atmospheric Chemistry: The Rate of Atmospheric NO Production,” to appear in Handbook of Atmospheric Electrodynamics, vol. 1, CRC Press, Boca Raton, Fla.
4. W. H. Schlesinger, Biogeochemistry: An Analysis of Global Change, Academic, San Diego (1991).
5. R. Ayres, W. Schlesinger, R. Socolow, in Industrial Ecology and Global Change, R. Socolow, C. Andrews, F. Berkhout, V. Thomas, eds., Cambridge U.P., Cambridge, England (1994), p. 121.
6. R. Söderlund, T. Rosswall, in The Natural Environment and the Biogeochemical Cycles, O. Hutzinger, ed., Springer‐Verlag, New York (1982), p. 61.
7. J. Sprent, The Ecology of the Nitrogen Cycle, Cambridge U.P., Cambridge, England (1987).
8. E. A. Paul, F. E. Clark, Soil Microbiology and Biochemistry, Academic, San Diego (1989).
9. J. Harte, A. P. Kinzig, Am. Naturalist 141, 829 (1993).
A. P. Kinzig, “Mutualism and Competition Between Plants and Microorganisms: Implications for Nitrogen Allocation in Terrestrial Ecosystems,” PhD dissertation, U. of Calif., Berkeley (1994).
10. P. M. Vitousek, W. A. Reiners, BioScience 25, 361 (1975). https://doi.org/BISNAS
P. M. Vitousek, L. R. Walker, in Colonization. Succession, and Stability, A. J. Gray, M. J. Crawley, P. J. Edwards, eds., Blackwell Scientific, Oxford (1986), p. 207.
11. J. D. Aber, J. M. Melillo, Terrestrial Ecosystems, Saunders, Philadelphia (1991).
P. M. Vitousek, P. A. Matson, in Biogeochemistry of Global Change, R. S. Oremland, ed., Chapman and Hall, New York (1991), p. 193.
12. Natl. Res. Council, Soil and Water Quality: An Agenda for Agriculture, Natl. Acad. P., Washington, D.C. (1993).
13. K. M. Constant, W. F. Sheldrick, World Nitrogen Survey, World Bank, Washington, D.C. (1992).
14. W. H. Schlesinger, A. E. Hartley, Biogeochemistry 15, 191 (1992).https://doi.org/BIOGEP
15. H. W. Paerl, Can. J. Fisheries Aquatic Sci. 50, 2254 (1993).
16. J. P. D. Abbatt, M. J. Molina, Annu. Rev. Energy Environment 18, 1 (1993).
17. G. Brasseur, S. Solomon, Aeronomy of the Middle Atmosphere: Chemistry and Physics of the Stratosphere and Mesosphere, Reidel, Dordrecht, The Netherlands (1984).
18. P. A. Steudler, R. D. Bowden, J. M. Melillo, J. D. Aber, Nature 341, 314 (1989).https://doi.org/NATUAS
19. E. B. Rastetter, M. G. Ryan, G. R. Shaver, J. M. Melillo, K. J. Nadelhoffer, J. E. Hobbie, J. D. Aber, Tree Physiol. 9, 101 (1991).
20. D. W. Schindler, S. E. Bayley, Global Biogeochem. Cycles 7, 717 (1993).https://doi.org/GBCYEP
21. C. R. Carroll, J. H. Vandermeer, P. M. Rosset, Agroecology, McGraw‐Hill, New York (1990).
22. US Dept. of Agriculture, Agricultural Statistics 1989, US Govt. Printing Office, Washington, D.C. (1989).
23. See, for instance, D. A. Jaffe, in Global Biogeochemical Cycles, S. S. Butcher, R. J. Charlson, G. H. Orians, G. V. Wolfe. eds., Academic, San Diego (1992), p. 263.
24. B. N. Richards, The Microbiology of Terrestrial Ecosystems, Longman Scientific and Technical, Harlow, England (1987).

More about the Authors

Ann P. Kinzig. Princeton University, Princeton, New Jersey.

Robert H. Socolow. Center for Energy and Environmental Studies, Princeton.