Skip to main content Accessibility help
×
Home
  • Get access
    Check if you have access via personal or institutional login
  • Cited by 1
  • Print publication year: 2014
  • Online publication date: June 2014

Chapter Seven - Traits, states and rates: understanding coexistence in forests

Summary

Introduction: why do tree species coexist?

The question of why there is more than one plant species on Earth is probably not one for ecology. Rather, it would appear to us at least that it is up to systems biology and evolutionary biology to explain why the enormous variation in structure and function exhibited by individual plants – a variation that makes sense given the huge range of physical environments that they occupy – occurs primarily as species-to-species variation, rather than as variation among ecotypes via local adaptation, or variation among individuals via phenotypic plasticity. However, given that plant species are so very different, the question of why we appear to observe the long-term co-occurrence of multiple species in the same region certainly is a question for ecology, so much so that the paradox of coexistence has remained central to community ecology for decades (e.g. Gause 1934; Grubb 1977; Hutchinson 1961; MacArthur 1970).

An important recent development has been the realisation, thanks to neutral theory, that the long-term co-occurrence of multiple taxonomic species is not, by itself, a paradox at all (Chave 2004; Hubbell 2001). We now know that it could take an enormous amount of time for a mixed community to drift to monodominance in any one region, if species were indistinguishable in terms of their traits. But this still leaves the challenge of explaining why we observe the long-term co-occurrence of species that are measurably different in traits that obviously affect fitness, such as growth, mortality and reproductive rates (see Purves & Turnbull 2010). Theoretical ecology has provided one kind of answer to this question, by identifying a suite of fundamental mechanisms that can maintain the coexistence of multiple species (Chesson 2000a). Although it is likely that there are new mechanisms still to be discovered, theoretical ecologists are almost entirely agreed that coexistence requires some form of negative feedback: if one species becomes too dominant, its performance declines, which in turn reduces its abundance; the opposite occurs for species that drift to abundances that are too low (Chesson 2000a; and for forests see Dislich, Johst & Huth 2010). In the presence of such negative feedbacks, communities can exhibit stable coexistence of multiple species, where the community exhibits a typical mixture of species (or mixture of traits) that it tends to return to after perturbations.

References
Adams, T. A., Purves, D. W. & Pacala, S. W. (2007a) Understanding height-structured competition in forests: is there an R for light?Proceedings of the Royal Society Series B, 274, 3039–3048.
Adams, T. A., Purves, D. W. & Pacala, S. W. (2007b) Understanding height-structured competition in forests: is there an R for light? (erratum)Proceedings of the Royal Society Series B, 275, 591.
Adler, F. R. & Mosquera, J. M. (2000) Is space necessary? Interference competition and limits to biodiversity. Ecology, 81, 3226–3232.
Adler, P. B., HilleRisLambers, J. & Levine, J. M. (2007) A niche for neutrality. Ecology Letters, 10, 95–104.
Botkin, D. B., Wallis, J. R. & Janak, J. F. (1972) Some ecological consequences of a computer model of forest growth. Journal of Ecology, 60, 849–872.
Bugmann, H. (2001) A review of forest gap models. Climatic Change, 51, 259–305.
Burns, R. M. & Honkala, B. H. (1990a) Silvics of North America: Conifers. Washington, DC: USDA Forest Service.
Burns, R. M. & Honkala, B. H. (1990b) Silvics of North America: Hardwoods. Washington, DC: USDA Forest Service.
Cáceres, C. (1997) Temporal variation, dormancy, and coexistence: a field test of the storage effect. Proceedings of the National Academy of Science USA, 94, 9171–9175.
Canham, C. D. (1994) Causes and consequences of resource heterogeneity in forests: interspecific variation in light transmission by canopy trees. Canadian Journal of Forest Research, 24, 337–349.
Chave, J. (2004) Neutral theory and community ecology. Ecology Letters, 7, 241–253.
Chesson, P. (2000a) Mechanisms of maintenance of species diversity. Annual Review of Ecology and Systematics, 31, 343–366.
Chesson, P. (2000b) General theory of competitive coexistence in spatially-varying environments. Theoretical Population Biology, 58, 211–237.
Clark, J. S., Dietz, M., Chakraborty, S. et al. (2007) Resolving the biodiversity paradox. Ecology Letters, 10, 647–659.
Clark, J. S., LaDeau, S. & Ibanez, I. (2004) Fecundity of trees and the colonization-competition hypothesis. Ecological Monographs, 74, 415–442.
Coates, K. D., Canham, C. D., Beaudet, M., Sachs, D. L. & Messier, C. (2003) Use of a spatially explicit individual-tree model (SORTIE/BC) to explore the implications of patchiness in structurally complex forests. Forest Ecology and Management, 186, 297–310.
Comita, L. S., Muller-Landau, H. C., Aguilar, S. & Hubbell, S. P. (2010) Asymmetric density dependence shapes species abundances in a tropical tree community. Science, 329, 330–332.
Connell, J. H. (1971) On the role of natural enemies in preventing competitive exclusion in some marine animals and in rain forest trees. In Dynamics of Populations (eds. den Boer, B. J. & Gradwell, G. R.), pp. 298–310. Wageningen: Centre for Agricultural Publishing and Documentation.
Coomes, D. A. & Grubb, P. J. (2003) Colonization, tolerance, competition and seed-size variation within functional groups. Trends in Ecology & Evolution, 18, 283–291.
Cowles, H. C. (1899) The ecological relations of the vegetation on the sand dunes of Lake Michigan. Part I: Geographical relations of the dune floras. Botanical Gazette, 27, 95–117.
Di Lucca, C. M. (1998) TASS/SYLVER/TIPSY: systems for predicting the impact of silvicultural practices on yield, lumber value, economic return and other benefits. In Stand Density Management Conference: Using the Planning Tools (ed. Bamsey, C. R.), pp. 7–16. Edmonton: Clear Lake Ltd.
Dislich, C., Johst, K. & Huth, A. (2010) What enables coexistence in plant communities? Weak versus strong species traits and the role of local processes. Ecological Modelling, 221, 2227–2236.
Dixon, G. E. (2002) Essential FVS: A User’s Guide to the Forest Vegetation Simulator. Internal Report. Fort Collins, CO: USDA Forest Service, Forest Management Service Center.
Du, X., Zhou, S. & Etienne, R. S. (2011) Negative density dependence can offset the effect of species competitive asymmetry: a niche-based mechanism for neutral-like patterns. Journal of Theoretical Biology, 278, 127–134.
Dybzinski, R. & Tilman, D. (2009) Competition and coexistence in plant communities. In The Princeton Guide to Ecology (ed. Levin, S.). Princeton, NJ: Princeton University Press.
Freckleton, R. P. & Lewis, O. T. (2006) Pathogens, density dependence and the coexistence of tropical trees. Proceedings of the Royal Society Series B, 273, 2909–2916.
Gause, G. F. (1934) The Struggle for Existence. Baltimore: William and Wilkins.
Gause, G. F. & Witt, A. A. (1935) Behavior of mixed populations and the problem of natural selection. American Naturalist, 69, 596–609.
Grubb, P. J. (1977) The maintenance of species-richness in plant communities: the importance of the regeneration niche. Biological Reviews, 52, 107–145.
Harms, K. E., Wright, S. J., Calderon, O., Hernandez, A. & Herre, E. A. (2000) Pervasive density-dependent recruitment enhances seedling diversity in a tropical forest. Nature, 404, 493–495.
Hubbell, S. P. (2001) The Unified Neutral Theory of Biodiversity and Biogeography. Princeton, NJ: Princeton University Press.
Hutchinson, G. E. (1961) The paradox of the plankton. American Naturalist, 882, 137–145.
Huth, A. & Ditzer, T. (2000) Simulation of the growth of a Dipterocarp lowland rain forest with FORMIX3. Ecological Modelling, 134, 1–25.
Kohler, P. & Huth, A. (1998) The effect of tree species grouping in tropical rain forest modelling – Simulation with the individual based model FORMIND. Ecological Modelling, 109, 301–321.
Kohyama, T. (1993) Size-structured tree populations in gap-dynamic forest – the forest architecture hypothesis for the stable coexistence of species. Journal of Ecology, 81, 131–143.
Kohyama, T. & Takada, T. (2009) The stratification theory for plant coexistence promoted by one-sided competition. Journal of Ecology, 97, 463–471.
Körner, C. (2004) Through enhanced tree dynamics carbon dioxide enrichment may cause tropical forests to lose carbon. Philosophical Transactions of the Royal Society Series B, 359, 493–498.
Janzen, D. H. (1970) Herbivores and the number of tree species in tropical forests. American Naturalist, 104, 501–508.
Johnson, D. J., Beaulieu, W. T., Bever, J. D. & Clay, K. (2012) Conspecific negative density dependence and forest diversity. Science, 336, 904–907.
Leibold, M. A., Holyoak, M., Mouquet, N. et al. (2004) The metacommunity concept: a framework for multi-scale community ecology. Ecology Letters, 7, 601–613.
Leibold, M. A. & McPeek, M. A. (2006) Coexistence of the niche and neutral perspectives in community ecology. Ecology, 87, 1399–1410.
Levine, J. M. & HilleRisLambers, J. (2009) The importance of niches for the maintenance of species diversity. Nature, 461, 254–257.
Lichstein, J. W., Dushoff, J., Levin, S. A. & Pacala, S. W. (2007) Intraspecific variation and species coexistence. American Naturalist, 170, 807–818.
Lichstein, J. W. & Pacala, S. W. (2011) Local diversity in heterogeneous landscapes: quantitative assessment with a height-structured forest metacommunity model. Theoretical Ecology, 4, 269–281.
MacArthur, R. (1970) Species packing and competitive equilibrium for many species. Theoretical Population Biology, 1, 1–11.
Mangan, S. A., Schnitzer, S. A., Herre, E. A. et al. (2010) Negative plant-soil feedback predicts tree-species relative abundance in a tropical forest. Nature, 466, 752–755.
Muller-Landau, H. C. & Adler, F. R. (2007) How seed dispersal affects interactions with specialized natural enemies and their contribution to diversity maintenance. In Seed Dispersal: Theory and its Application in a Changing World (eds. Dennis, A. J., Schupp, E. W., Green, R. J. & Westcott, D. W.) pp. 407–426. Wallingford: CAB International.
Murrell, D. J. & Law, R. (2002) Heteromyopia and the spatial coexistence of similar competitors. Ecology Letters, 6, 48–59.
Montoya, D., Zavala, M. A., Rodríguez, M. A. & Purves, D. W. (2008) Animal versus wind dispersal and the robustness of tree species to deforestation. Science, 320, 1502–1504.
Nyland, R. D. (2007) Silviculture: Concepts and Applications. Boston: Waveland Press.
Ogle, K. & Pacala, S. W. (2009) A modeling framework for inferring tree growth and allocation from physiological, morphological, and allometric traits. Tree Physiology, 29, 587–605.
Oliver, C. D. & Larson, B. C. (1996) Forest Stand Dynamics. New York: Wiley.
Pacala, S. W., Canham, C. D., Saponara, J., Silander, J. A. & Kobe, R. K. (1996) Forest models defined by field measurements: estimation, error analysis and dynamics. Ecological Monographs, 66, 1–43.
Pacala, S. W. & Rees, M. (1998) Models suggesting field experiments to test two hypotheses explaining successional diversity. American Naturalist, 152, 729–737.
Pake, C. & Venable, D. L. (1995) Is coexistence of Sonoran desert annual plants mediated by temporal variability reproductive success. Ecology, 76, 246–261.
Puettman, K. J., Coates, D. & Messier, C. C. (2008) A Critique of Silviculture. Washington: Island Press.
Purves, D. W. & Dushoff, J. (2005) Directed seed dispersal and metapopulation response to habitat loss and disturbance: application to Eichhornia paniculata. Journal of Ecology, 93, 658–669.
Purves, D. W., Lichstein, J. W., Strigul, N. & Pacala, S. W. (2008) Predicting and understanding forest dynamics using a simple tractable model. Proceedings of the National Academy of Sciences USA, 105, 17018–17022.
Purves, D. W. & Pacala, S. W. (2008) Predictive models of forest dynamics. Science, 320, 1452–1453.
Purves, D. W. & Turnbull, L. A. (2010) Different but equal: the implausible assumption at the heart of neutral theory. Journal of Animal Ecology, 79, 1215–1225.
Shugart, H. H. (1984) A Theory of Forest Dynamics: The Ecological Implications of Forest Succession Models. New York: Springer-Verlag.
Stage, A. R. (1973) Prognosis Model for Stand Development. Research Paper INT-137. Ogden, UT: USDA Forest Service, Intermountain Forest and Range Experiment Station.
Sterck, F. J., Poorter, L. & Schieving, F. (2006) Leaf traits determine the growth-survival trade-off across rain forest tree species. The American Naturalist, 167, 758–765.
Strigul, N., Pristinski, D., Purves, D. W., Dushoff, J. & Pacala, S. W. (2007) Scaling from trees to forests: tractable macroscopic equations for forest dynamics. Ecological Monographs, 78, 523–545.
Tilman, D. (1982) Resource Competition and Community Structure. Monographs in Population Biology Vol. 17. Princeton, NJ: Princeton University Press.
Tilman, D. (1994) Competition and biodiversity in spatially structured habitats. Ecology, 75, 2–16.
Webb, C. O. & Peart, D. R. (1999) Seedling density dependence promotes coexistence of Bornean rain forest trees. Ecology, 80, 2006–2017.
Whittaker, R. H. (1956) Vegetation of the great smoky mountains. Ecological Monographs, 26, 1–80.
Whittaker, R. H. (1960) Vegetation of siskiyou mountains, Oregon and Washington. Ecological Monographs, 30, 279–338.
Wright, S. J. (2002) Plant diversity in tropical forests: a review of mechanisms of species coexistence. Oecologia, 130, 1–14.