Elevated CO2 increases productivity and invasive species success in an arid ecosystem

Article metrics

Abstract

Arid ecosystems, which occupy about 20% of the earth's terrestrial surface area, have been predicted to be one of the most responsive ecosystem types to elevated atmospheric CO2 and associated global climate change1,2,3. Here we show, using free-air CO2 enrichment (FACE) technology in an intact Mojave Desert ecosystem4, that new shoot production of a dominant perennial shrub is doubled by a 50% increase in atmospheric CO2 concentration in a high rainfall year. However, elevated CO2 does not enhance production in a drought year. We also found that above-ground production and seed rain of an invasive annual grass increases more at elevated CO2 than in several species of native annuals. Consequently, elevated CO2 might enhance the long-term success and dominance of exotic annual grasses in the region. This shift in species composition in favour of exotic annual grasses, driven by global change, has the potential to accelerate the fire cycle, reduce biodiversity and alter ecosystem function in the deserts of western North America.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1
Figure 2: The relative ratio (elevated CO2/ambient CO2) of plant density (left), above-ground plant biomass (centre) and seed rain (total seed production; right) per unit area at the Nevada Desert FACE Facility in May, 1998.

References

  1. 1

    Strain, B. R. & Bazzaz, F. A. in CO2 and Plants: The Response of Plants to Rising Levels of Carbon Dioxide (ed. Lemon, E.) 177–222 (AAAS, Washington DC, 1983).

  2. 2

    Melillo, J. M. et al. Global climate change and terrestrial net primary production. Nature 363, 234–240 (1993).

  3. 3

    Smith, S. D., Monson, R. K. & Anderson, J. E. Physiological Ecology of North American Desert Plants (Springer, Berlin, 1997).

  4. 4

    Jordan, D. N. et al. Biotic, abiotic and performance aspects of the Nevada Desert Free-Air CO2 Enrichment (FACE) Facility. Global Change Biol. 5, 659–668 ( 1999).

  5. 5

    Bazzaz, F. A. The response of natural ecosystems to rising global CO2 levels. Annu. Rev. Ecol. Syst. 21, 167– 196 (1990).

  6. 6

    Smith, S. D., Strain, B. R. & Sharkey, T. D. Effects of CO2 enrichment on four Great Basin grasses. Funct. Ecol. 1, 139– 143 (1987).

  7. 7

    Mayeux, H. S., Johnson, H. B. & Polley, H. W. in Ecology and Management of Annual Grasslands (eds Monsen, S. B. & Kitchen, S. G.) 95–100 (US Forest. Serv. Gen. Tech. Rep. INT-GTR-313, Ogden, Utah, USA, 1994).

  8. 8

    Sage, R. F. in Carbon Dioxide, Populations and Communities (eds Körner, C. & Bazzaz, F. A.) 231–249 (Academic, San Diego, 1996).

  9. 9

    Naeem, S., Thompson, L. J., Lawler, S. P., Lawton, J. H. & Woodfin, R. M. Declining biodiversity can alter the performance of ecosystems. Nature 368, 734–737 (1994).

  10. 10

    Hendrey, G. R. & Kimball, B. A. The FACE program. Agric. For. Meteorol. 70, 3– 14 (1994).

  11. 11

    Hunter, R. Bromus invasions on the Nevada Test Site: present status of B. rubens and B. tectorum with notes on their relationship to disturbance and altitude. Great Basin Nat. 51, 176– 182 (1991).

  12. 12

    Schlesinger, W. H., Raikes, J. A., Hartley, A. E. & Cross, A. F. On the spatial pattern of soil nutrients in desert ecosystems. Ecology 77, 364–374 ( 1996).

  13. 13

    Huxman, T. E., Hamerlynck, E. P. & Smith, S. D. Reproductive allocation and seed production in Bromus madritensis ssp. rubens at elevated CO2. Funct. Ecol. 13, 769–777 (2000).

  14. 14

    Huxman, T. E. et al. The effects of parental CO2 on seed quality and subsequent seedling performance in Bromus rubens. Oecologia 114, 202–208 ( 1998).

  15. 15

    Brown, J. H. & Heske, E. J. Control of a desert-grassland transition by a keystone rodent guild. Science 250, 1705–1707 (1990).

  16. 16

    DeLucia, E. H. et al. Net primary production of a forest ecosystem with experimental CO2 enrichment. Science 284, 1177–1179 (1999).

  17. 17

    Hamerlynck, E. P. et al. Photosynthetic responses of Larrea tridentata to a step-increase in atmospheric CO2 at the Nevada Desert FACE Facility. J. Arid Environ. 44, 425– 436 (2000).

  18. 18

    Huxman, T. E. et al. Photosynthetic down-regulation in Larrea tridentata exposed to elevated atmospheric CO2: interaction with drought under glasshouse and field (FACE) exposure. Plant Cell Environ. 21, 1153–1161 (1998).

  19. 19

    Noy-Meir, I. Desert ecosystems: environment and producers. Annu. Rev. Ecol. Syst. 4, 51–58 ( 1973).

  20. 20

    Mack, R. N. The invasion of Bromus tectorum L. into western North America: an ecological chronicle. Agro-Ecosystems 7, 145– 165 (1981).

  21. 21

    Knapp, P. A. Spatio-temporal patterns of large grassland fires in the Intermountain West, U.S.A. Global Ecol. Biogeogr. Lett. 7, 259 –272 (1998).

  22. 22

    Young, J. A. & Evans, R. A. Population dynamics after wildfires in sagebrush grasslands. J. Range Manage. 31, 283–289 (1978).

  23. 23

    Melgoza, G., Nowak, R. S. & Tausch, R. J. Soil water exploitation after fire: competition between Bromus tectorum (cheatgrass) and two native species. Oecologia 83, 7–13 (1990 ).

Download references

Acknowledgements

We thank D. Jordan, E. Knight, G. Hendrey and the Brookhaven National Laboratory for technical support; C. Biggart, L. DeFalco, C. Grant, E. Hamerlynck, M. Hargrove, K. Hightower, K. Huxman, F. Landau, D. Pataki, K. Salsman, T. Shiver, D. Stortz-Lintz, and M. Taub for field and laboratory assistance; and J. Titus for soil nitrogen data. Financial support was provided by the DOE- and NSF-EPSCoR programs and panel grants from NSF/TECO and DOE/TCP, and additional support was provided by the NAES. We also thank the DOE/Nevada Operations Office and Bechtel Nevada for site operations support.

Author information

Correspondence to Stanley D. Smith.

Rights and permissions

Reprints and Permissions

About this article

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.