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Changes in tree species abundance in a Neotropical forest: impact of climate change

Published online by Cambridge University Press:  10 July 2009

Richard Condit
Affiliation:
Smithsonian Tropical Research Institute, Unit 0948, APO A A 34002-0948, USA; or Apartado 2072, Balboa, Ancón, Panamá
Stephen P. Hubbell
Affiliation:
Smithsonian Tropical Research Institute, Unit 0948, APO A A 34002-0948, USA; or Apartado 2072, Balboa, Ancón, Panamá Department of Ecology, Evolution and Behavior, Princeton University, Princeton, New Jersey 08544, USA
Robin B. Foster
Affiliation:
Smithsonian Tropical Research Institute, Unit 0948, APO A A 34002-0948, USA; or Apartado 2072, Balboa, Ancón, Panamá Department of Botany, Field Museum of Natural History, Chicago, Illinois 60605, USA

Abstract

The abundance of all tree and shrub species has been monitored for eight years in a 50 ha census plot in tropical moist forest in central Panama. Here we examine population trends of the 219 most numerous species in the plot, assessing the impact of a long-term drying trend. Population change was calculated as the mean rate of increase (or decrease) over eight years, considering either all stems ≥10 mm diameter at breast height (dbh) or just stems ≥100 mm dbh. For stems ≥10 mm, 40% of the species had mean growth rates <1% per year (either increasing or decreasing) and 12% had changes ≥5% per year. For stems ≥100 mm, the figures were 38% and 8%.

Species that specialize on the slopes of the plot, a moist microhabitat relative to the plateau, suffered significantly more declines in abundance than species that did not prefer slopes (stems ≥10 mm dbh). This pattern was due entirely to species of small stature: 91% of treelets and shrubs that were slope-specialists declined in abundance, but just 19% of non-slope treelets and shrubs declined. Among larger trees, slope and non-slope species fared equally. For stems ≥100 mm dbh, the slope effect vanished because there were few shrubs and treelets with stems ≥100 mm dbh. Another edaphic guild of species, those occurring preferentially in a small swamp in the centre of the plot, were no more likely to decline in abundance than non-swamp species, regardless of growth form. Species that preferentially colonize canopy gaps in the plot were slightly more likely to decrease in abundance than non-colonizing species (only for stems ≥10 mm dbh, not ≥100 mm). Despite this overall trend, however, several colonizing species had the most rapidly increasing populations in the plot.

The impact of a 25-year drying trend and an associated increase in the severity of the 4-month dry season is having an obvious impact on the BCI forest. At least 16 species of shrubs and treelets with affinities for moist microhabitats are headed for extinction in the plot. Presumably, these species invaded the forest during a wetter period prior to 1966. A severe drought of 1983 that caused unusually high tree mortality contributed to this trend, and may also have been responsible for sharp increases in abundance of a few gap-colonizers because it temporarily opened the forest canopy. The BCI forest is remarkably sensitive to a subtle climatic shift, yet we do not know whether this is typical for tropical forests because no other large-scale censuses exist for comparison.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1996

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References

LITERATURE CITED

Becker, P. & Castillo, A. 1990. Root architecture of shrubs and saplings in the understorey of a tropical moist forest in lowland Panama. Biotropica 22:242249.CrossRefGoogle Scholar
Becker, P., Rabenold, P. E., Idol, J. R. & Smith, A. P. 1988. Water potential gradients for gaps and slopes in a Panamanian tropical moist forest's dry season. Journal of Tropical Ecology 4:173184.CrossRefGoogle Scholar
Becker, P. & Smith, A. P. 1990. Spatial autocorrelation of solar radiation in a tropical moist forest understorey. Agricultural and Forest Meteorology 52:373379.CrossRefGoogle Scholar
Botkin, D. B. & Nisbet, R. A. 1992. Projecting the effects of climate change on biological diversity in forests. Pp. 277293 in Peters, R. L. & Lovejoy, T. E. (eds). Global warming and biological diversity. Yale University Press, New Haven.Google Scholar
Bradley, R. S., Diaz, H. F., Eischeid, J. K., Jones, P. D., Kelly, P. M. & Goodess, C. M. 1987. Precipitation fluctuations over northern hemisphere land areas since the mid-19th century. Science 237:171175.CrossRefGoogle ScholarPubMed
Bush, M. B. & Colinvaux, P. A. 1990. A pollen record of a complete glacial cycle from lowland Panama. Journal of Vegetation Science 1:105118.CrossRefGoogle Scholar
Bush, M. B., Colinvaux, P. A., Wiemann, M. C., Piperno, D. R. & Liu, K. 1990. Late pleistocene temperature depression and vegetation change in Ecuadorian Amazonia. Quaternary Research 34:330345.CrossRefGoogle Scholar
Condit, R. 1995. Research in large, long-term tropical forest plots. Trends in Ecology and Evolution 10:1822.CrossRefGoogle ScholarPubMed
Condit, R., Hubbell, S. P. & Foster, R. B. 1992a. Recruitment near conspecific adults and the maintenance of tree and shrub diversity in a neotropical forest. American Naturalist 140:261286.CrossRefGoogle Scholar
Condit, R., Hubbell, S. P. & Foster, R. B. 1992b. Stability and change of a neotropical moist forest over a decade. Bioscience 42:822828.CrossRefGoogle Scholar
Condit, R., Hubbell, S. P. & Foster, R. B. 1993a. Identifying fast-growing native trees from the neotropics using data from a large, permanent census plot. Forest Ecology and Management 62:123143.CrossRefGoogle Scholar
Condit, R., Hubbell, S. P. & Foster, R. B. 1993b. Mortality and growth of a commercial hardwood, ‘El Cativo’, Prioria copaifera, in Panama. Forest Ecology and Management 62:107122.CrossRefGoogle Scholar
Condit, R., Hubbell, S. P. & Foster, R. B. 1995. Mortality rates of 205 neotropical tree species and the responses to a severe drought. Ecological Monographs 65:419439.CrossRefGoogle Scholar
Croat, T. R. 1978. Flora of Barro Colorado Island. Stanford University Press, Stanford, California.Google Scholar
Dale, V. H. & Franklin, J. F. 1989. Potential effects of climate change on stand development in the Pacific Northwest. Canadian Journal of Forestry Research 19:15811590.CrossRefGoogle Scholar
D'Arcy, W. G. 1987. Flora of Panama. Part I: Introduction and checklist. Missouri Botanical Garden, St Louis, Missouri, USA. 328 + xxx pp.Google Scholar
Davis, M. B. 1981. Quaternary history and the stability of forest communities. Pp. 132153 in West, D. C., Shugart, H. H. & Botkin, D. B. (eds). Forest succession: concepts and applications. Springer-Verlag, New York.CrossRefGoogle Scholar
Delcourt, P. A. & Delcourt, H. R. 1987. Long term forest dynamics of the temperate zone: a case study of late quaternary forests in eastern North America. Springer-Verlag, New York.CrossRefGoogle Scholar
Diaz, H. F., Bradley, R. S. & Eischeid, J. K. 1989. Precipitation fluctuations over global land areas since the late 1800's. Journal of Geophysical Research 94:11951210.CrossRefGoogle Scholar
Foster, R. B. 1982a. Famine on Barro Colorado Island. Pp. 201212 in Leigh, E. G. Jr, Rand, S. A. & Windsor, D. M. (eds). The ecology of a tropical forest: seasonal rhythms and long-term changes. Smithsonian Institution Press, Washington, DC.Google Scholar
Foster, R. B. 1982b. The seasonal rhythm of fruitfall on Barro Colorado Island. Pp. 151172 in Leigh, E. G. Jr, Rand, S. A. & Windsor, D. M. (eds). The ecology of a tropical forest: seasonal rhythms and long-trem changes. Smithsonian Institution Press, Washington, DC.Google Scholar
Franklin, J. F., Swanson, F. J., Harmon, M. E., Perry, D. A., Spies, T. A., Dale, V. H., McKee, A., Ferrell, W. K., Means, J. E., Gregory, S. V., Lattin, J. D., Schowalter, T. D. & Larsen, D. 1992. Effects of global climatic change on forests in northwestern North America. Pp. 244257 in Peters, R. L. & Lovejoy, T. E. (eds). Global warming and biological diversity. Yale University Press, New Haven.Google Scholar
Hamilton, A. C. & Taylor, D. 1991. History of climate and forests in tropical Africa during the last 8 million years. Climate Change 19:6578.CrossRefGoogle Scholar
Hartshorn, G. S. 1992. Possible effects of global warming on the biological diversity in tropical forests. Pp. 137146 in Peters, R. L. & Lovejoy, T. E. (eds). Global warming and biological diversity. Yale University Press, New Haven.Google Scholar
Howe, H. F. 1990. Survival and growth of juvenile Virola surinamensis in Panama: effects of herbivory and canopy closure. Journal of Tropical Ecology 6:259280.CrossRefGoogle Scholar
Hubbell, S. P. & Foster, R. B. 1983. Diversity of canopy trees in a neotropical forest and implications for conservation. Pp. 2541 in Sutton, S. L., Whitmore, T. C. & Chadwick, A. C. (eds). Tropical rain forest: ecology and management. Blackwell Scientific Publications, Oxford.Google Scholar
Hubbell, S. P. & Foster, R. B. 1986a. Commonness and rarity in a neotropical forest: implications for tropical tree conservation. Pp. 205231 in Soulé, M. (ed.). Conservation biology: the science of scarcity and diversity. Sinauer Associates, Inc., Sunderland, Massachusetts.Google Scholar
Hubbell, S. P. & Foster, R. B. 1986b. Canopy gaps and the dynamics of a neotropical forest. Pp. 7796 in Crawley, M. J. (ed.). Plant ecology. Blackwell Scientific Publications, Oxford.Google Scholar
Hubbell, S. P. & Foster, R. B. 1987. The spatial context of regeneration in a neotropical forest. Pp. 395412 in Crawley, M., Edwards, P. J. & Gray, A. (eds). Colonization, succession, and stability. Blackwell Scientific Publications, Oxford, England.Google Scholar
Hubbell, S. P. & Foster, R. B. 1990a. Structure, dynamics, and equilibrium status of old-growth forest on Barro Colorado Island. Pp. 522541 in Gentry, A. (ed.). Four Neotropical rain forests. Yale University Press, New Haven.Google Scholar
Hubbell, S. P. & Foster, R. B. 1990b. The fate of juvenile trees in a neotropical forest: implications for the natural maintenance of tropical tree diversity. Pp. 325349 in Hadley, M. & Bawa, K. S. (eds). Reproductive ecology of tropical forest plants. Man and the Biosphere Series, Vol. 7. UNESCO/ IUBS, Paris, and Parthenon Publishing, Carnforth, UK.Google Scholar
Hubbell, S. P. & Foster, R. B. 1992. Short-term population dynamics of a neotropical forest: why ecological research matters to tropical conservation and management. Oikos 63:4861.CrossRefGoogle Scholar
Leigh, E. G. Jr, Rand, S. A. & Windsor, D. M. (eds). 1982. The ecology of a tropical forest: seasonal rhythms and long-term changes. Smithsonian Institution Press, Washington, DC.Google Scholar
Leigh, E. G. Jr, Windsor, D. M., Rand, S. A. & Foster, R. B. 1990. The impact of the ‘El Nino’ drought of 1982–1983 on a Panamanian semideciduous forest. Pp. 473486 in Glynn, P. W. (ed.). Global ecological consequences of the 1982–1983 El Nino-Southern Oscillation. Elsevier Press.CrossRefGoogle Scholar
Manokaran, N. & Kochummen, K. M. 1987. Recruitment, growth and mortality of tree species in a lowland dipterocarp forest in Peninsular Malaysia. Journal of Tropical Ecology 3:315330.CrossRefGoogle Scholar
Manokaran, N., LaFrankie, J. V., Kochummen, K. M., Quah, E. S., Klahn, J., Ashton, P. S. & Hubbell, S. P. 1992. Stand table and distribution of species in the 50-ha research plot at Pasoh Forest Reserve. Forest Research Institute of Malaysia, Research Data No. 1. 454 pp. Kepong, Malaysia.Google Scholar
Mulkey, S. S., Smith, A. P., Wright, S. J., Machado, J. L. & Dudley, R. 1994. Contrasting leaf phenotypes control seasonal variation in water loss in a tropical forest shrub. Proceedings of the National Academy of Sciences 89:90849088.CrossRefGoogle Scholar
O'Brien, S. T., Hayden, B. P. & Shugart, H. H. 1992. Global climatic change, hurricanes, and a tropical forest. Climatic Change 22:175190.CrossRefGoogle Scholar
Overpeck, J. T., Rind, D. & Goldberg, R. 1990. Climate-induced changes in forest disturbance and vegetation. Nature 343:5153.CrossRefGoogle Scholar
Pastor, J. & Post, W. M. 1988. Response of northern forests to CO2-induced climate change. Nature 344:5558.CrossRefGoogle Scholar
Phillips, O. L. & Gentry, A. H. 1994. Increasing turnover through time in tropical forests. Science 263:954958.CrossRefGoogle ScholarPubMed
Phillips, O. L., Hall, P., Gentry, A. H., Sawyer, S. A. & Vasquez, R. 1994. Dynamics and species richness of tropical rain forests. Proceedings of the National Academy of Science 91:28052809.CrossRefGoogle ScholarPubMed
Shugart, H. H. & Smith, T. M. 1992. Using computer models to project ecosystem response, habitat change, and wildlife diversity. Pp. 147157 in Peters, R. L. & Lovejoy, T. E. (eds). Global warming and biological diversity. Yale University Press, New Haven.Google Scholar
Solomon, A. M. 1986. Transient response of forests to CO2-induced climate change: simulation modeling experiments in eastern North America. Oecologia 68:567579.CrossRefGoogle Scholar
Sukumar, R., Dattaraja, H. S., Suresh, H. S., Radhakrishnan, J., Vasudeva, R., Nirmala, S. & Joshi, N. V. 1992. Long-term monitoring of vegetation in a tropical deciduous forest in Mudumalai, southern India. Current Science 62:608616.Google Scholar
Sukumar, R., Ramesh, R., Pant, R. K. & Rajagopalan, G. 1993. A δ13C record of late Quaternary climate change from tropical peats in southern India. Nature 364:703706.CrossRefGoogle Scholar
Swaine, M. D. & Whitmore, T. C. 1988. On the definition of ecological species groups in tropical rain forests. Vegetatio 75:8186.CrossRefGoogle Scholar
Urban, D. L., Harmon, M. E. & Halpern, C. B. 1993. Potential response of Pacific northwestern forests to climatic change, effects of stand and initial composition. Climatic Change 23:247266.CrossRefGoogle Scholar
Welden, C. W., Hewett, S. W., Hubbell, S. P. & Foster, R. B. 1991. Survival, growth, and recruitment of saplings in canopy gaps and forest understorey on Barro Colorado Island, Panama. Ecology 72:3550.CrossRefGoogle Scholar
Windsor, D. M. 1990. Climate and moisture variability in a tropical forest: long-term records from Barro Colorado Island, Panamá. Smithsonian Contribution to the Earth Sciences, No. 29. Smithsonian Institution Press, Washington, DC.Google Scholar
Windsor, D. M., Rand, A. S. & Rand, W. M. 1990. Características de la precipitatión en la isla de Barro Colorado. Pp. 53–71 in Leigh, E. G., Rand, A. S. & Windsor, D. M. (eds). Ecología de un bosque tropical: ciclos estacionales y cambios a largo plazo. Smithsonian Tropical Research Institute, Balboa, República de Panamá.Google Scholar
Woods, P. 1989. Effects of logging, drought, and fire on structure and composition of tropical forests in Sabah, Malaysia. Biotropica 21:290298.CrossRefGoogle Scholar
Wright, S. J. 1992. Seasonal drought, soil fertility and the species diversity of tropical forest plant communities. Trends in Ecology and Evolution 7:260263.CrossRefGoogle Scholar
Wright, S. J. & van Schaik, C. P. 1994. Light and the phenology of tropical trees. American Naturalist 143:192199.CrossRefGoogle Scholar
Zimmerman, J. K., Everham, E. M. III, Waide, R. B., Lodge, D. J., Taylor, C. M. & Brokaw, N. V. L. 1994. Responses of tree species to hurricane winds in subtropical wet forest in Puerto Rico: implications for tropical tree life histories. Journal of Ecology 82:911922.CrossRefGoogle Scholar