Community Ecology

, Volume 11, Issue 1, pp 97–104 | Cite as

Herbaceous and shrubby species co-occurrences in Brazilian savannas: the roles of fire and chance

  • I. A. SilvaEmail author
  • G. H. Carvalho
  • P. P. Loiola
  • M. V. Cianciaruso
  • M. A. Batalha


Competition and facilitation are expected to leave different signatures in the pattern of species co-occurrence. Competition may result in a given species pair occurring less often than expected by chance, whereas facilitation may result in a given species pair occurring more often than expected by chance. We assessed the co-occurrence of pairs of herbaceous and shrubby species in Brazilian savannas, asking (1) whether a given species pair occurs more often than expected by chance, (2) whether the number of species pairs in sites with frequent fires is higher than expected by chance, (3) whether the difference in the functional traits of heterospecific pairs is lower in sites with frequent fires, and (4) whether small environmental variations in each site - instead of species interactions - could explain the co-occurrence of species. We used null models to answer the first two questions, analyses of variance to answer the third question, and detrended correspondence analyses to answer the fourth question. In all studied sites, approximately half of the heterospecific pairs occurred more often than expected by chance. So, facilitation seems to be important in determining the co-occurrence of some species in Brazilian savannas. However, high fire frequencies changed the pattern of occurrence of the species pairs, resulting in a spatial signature indistinguishable from random. Frequent fires also promoted phenotypic clustering of species. Nevertheless, wherever fire frequency is reduced, competition may lead to phenotypic overdispersion of plant species. Thus, less harsh environmental conditions in savannas may increase the competition among plant species.


Cerrado Competition Facilitation Phenotypic clustering Phenotypic overdispersion Species co-occurrence Stress-gradient hypothesis 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Supplementary material

42974_2010_11010097_MOESM1_ESM.pdf (107 kb)
Supplementary material, approximately 109 KB.


  1. Arroyo, M.T.K., L.A. Cavieres, A. Peñaloza and M.A. Arroyo-Ka-lin. 2003. Positive associations between the cushion plant Azorella monantha (Apiaceae) and alpine plant species in the Chilean Patagonian Andes. Plant Ecol. 169: 121–129.Google Scholar
  2. Azaele, S., R. Muneepeerakul, A. Rinaldo and I. Rodriguez-Iturbe. 2010. Inferring plant ecosystem organization from species occurrences. J. Theor. Biol. 262: 323–329.PubMedGoogle Scholar
  3. Batalha, M.A. and F.R. Martins. 2002. The vascular flora of the cer-rado in Emas National Park (Goiás, central Brazil). Sida 20: 295–312.Google Scholar
  4. Bertness, M.D. and R.M. Callaway. 1994. Positive interactions in communities. Trends Ecol. Evol. 9: 191–193.PubMedGoogle Scholar
  5. Brooker, R.W., F.T. Maestre, R.M. Callaway, C.L. Lortie, L. Cavieres, G. Kunstler, P. Liancourt, K. Tielbörger, J.M.J. Travis, F. Anthelme, C. Armas, L. Coll, E. Corcket, S. Delzon, E. Forey, Z. Kikvidze, J. Olofsson, F. Pugnaire, C.L. Quiroz, P. Saccone, K. Schiffers, M. Seifan, B. Touzard and R. Michalet. 2008. Facilitation in plant communities: the past, the present and the future. J. Ecol. 96: 18–34.Google Scholar
  6. Bruno, J.F., J.J. Stachowicz and M.D. Bertness. 2003. Inclusion of facilitation into ecological theory. Trends Ecol. Evol. 18: 119–125.Google Scholar
  7. Butterfield, B.J. 2009. Effects of facilitation on community stability and dynamics: synthesis and future directions. J. Ecol. 97: 1192–1201.Google Scholar
  8. Callaway, R.M. 1995. Positive interactions among plants. Bot. Rev. 61: 306–349.Google Scholar
  9. Callaway, R.M. and L.R. Walker. 1997. Competition and facilitation: a synthetic approach to interactions in plants communities. Ecology 78: 1958–1965.Google Scholar
  10. Canales, J., M.C. Trevisan, J.F. Silva and H. Caswell. 1994. A demographic study of an annual grass (Andropogon brevifolius Schwartz) in burnt and unburnt savanna. Acta Oecol. 15: 261–274.Google Scholar
  11. Cavender-Bares, J., A. Keen and B. Miles. 2006. Phylogenetic structure of Floridian plant communities depends on taxonomic and spatial scale. Ecology 87: S109–S122.PubMedGoogle Scholar
  12. Cavieres L.A., M.T.K. Arroyo, A. Peñaloza, M. Molina-Montenegro and C. Torres. 2002. Nurse effect of Bolax gummnifera cushion plants in the alpine vegetation of the Chilean Patagonian Andes. J. Veg. Sci. 13: 547–554.Google Scholar
  13. Cavieres, L.A. and E.I. Badano. 2009. Do facilitative interactions increase species richness at the entire community level? J. Ecol. 97: 1181–1191.Google Scholar
  14. Choler, P., R. Michalet and R.M. Callaway. 2001. Facilitation and competition on gradients in alpine plant communities. Ecology 82: 3295–3308.Google Scholar
  15. Collins, S.P. and S.C. Klahr. 1991. Tree dispersion in oak dominated forests along an environmental gradient. Oecologia 86: 471–477.PubMedGoogle Scholar
  16. Condit, R., P.S. Ashton, P. Baker, S. Bunyavejchewin, S. Gunatilleke, N. Gunatilleke, S.P. Hubbell, R.B. Foster, A. Itoh, J.V. LaFrankie, , H.S. Lee, E. Losos, N. Manokaran, R. Sukumar and T. Yamakura. 2000. Spatial patterns in the distribution of tropical tree species. Science 288: 1414–1418.PubMedPubMedCentralGoogle Scholar
  17. Cornelissen, J.H.C., S. Lavorel, E. Garnier, S. Díaz, N. Buchmann, D.E. Gurbich, P.B. Reich, H. Steege, H.D. Morgan, M.G.A. Heijden van der, J.G. Pausas and H. Pooter. 2003. A handbook of protocols for standardized and easy measurement of plant fuctional trait worldwide. Aust. J. Bot. 51: 335–380.Google Scholar
  18. Coutinho, L.M. 1990. Fire in the ecology of the Brazilian cerrado. In: J.G. Goldammer (ed.), Fire in the Tropical Biota. Springer, Berlin, pp. 81–103.Google Scholar
  19. Dullinger, S., I. Kleinbauer, H. Pauli, M. Gottfried, R. Brooker, L. Nagy, J.P. Theurillat, J.I. Holten, O. Abdaladze, J.L. Benito, J.L. Borel, G. Coldea, D. Ghosn, R. Kanka, A. Merzouki, C. Klettner, P. Moiseev, U. Molau, K. Reiter, G. Rossi, A. Stancisi, M. Tomaselli, P. Unterlugauer, P. Vittoz and G. Grabherr. 2007. Weak and variable relationships between environmental severity and small-scale co-occurrence in alpine plant communities. J. Ecol. 95: 1284–1295.Google Scholar
  20. Fargione, J., C.S. Brown and D. Tilman. 2003. Community assembly and invasion: An experimental test of neutral versus niche processes. Proc. Nat. Acad. Sci. USA 100: 8916–8920.PubMedGoogle Scholar
  21. França, H., M.B. Ramos-Neto, A. Setzer. 2007. O fogo no Parque Nacional das Emas. Instituto do Meio Ambiente e dos Recursos Naturais Renováveis (Ibama), Brasília.Google Scholar
  22. Fukami, T., T.M. Bezemer, S.R. Mortimer and W.H. van der Putten. 2005. Species divergence and trait convergence in experimental plant community assembly. Ecol. Lett. 8: 1283–1290.Google Scholar
  23. Goldberg, D. and A. Novoplansky. 1997. On the relative importance of competition in unproductive environments. J Ecol. 85: 409–418.Google Scholar
  24. Gotelli, N.J. and A.M. Ellison. 2002. Assembly rules for New England ant assemblages. Oikos 99: 591–599.Google Scholar
  25. Gotelli, N.J. and K. Rohde. 2002. Co-occurrence of ectoparasites of marine fishes: a null model analysis. Ecol. Lett. 5: 86–94.Google Scholar
  26. Greenlee, J. and R.M. Callaway. 1996. Effect of abiotic stress on the relative importance of interference and facilitation. Am. Nat. 148: 386–396.Google Scholar
  27. Grime, J.P. 1973. Competitive exclusion in herbaceous vegetation. Nature 242: 344–347.Google Scholar
  28. Grime, J.P. 2001. Plant Strategies, Vegetation Processes, and Ecosystem Properties. John Wiley & Sons, Chichester.Google Scholar
  29. Gottsberger, G. and I. Silberbauer-Gottsberger. 2006. Life in the Cer-rado: A South American Tropical Seasonal Vegetation. Vol. 1. Origin, Structure, Dynamics and Plant Use. Reta, Ulm.Google Scholar
  30. Holzapfel, C., K. Tielbörger, H.A. Parag, J. Kigel and M, Sternberg. 2006. Annual plant–shrub interactions along an aridity gradient. Basic Appl. Ecol. 7: 268–279.Google Scholar
  31. Hubbell, S.P. 2001. The Unified Neutral Theory of Biodiversity and Biogeography. Princeton University, New Jersey.Google Scholar
  32. Hubbell, S.P., J. A Ahumada, R.Condit and R.B. Foster. 2001. Local neighbourhood effects on long-term survival of individual trees in a neotropical forest. Ecol. Res. 16: 859–875.Google Scholar
  33. Hurlbert, S.H. 1984. Pseudoreplication and the design of ecological field experiments. Ecol. Monogr. 54: 187–211.Google Scholar
  34. Johnson, M.T.J. and J.R. Stinchcombe. 2007. An emerging synthesis between community ecology and evolutionary biology. Trends Ecol. Evol. 22: 250–257.PubMedGoogle Scholar
  35. Jongman, R.H.G., C.F.J. ter Braak and O.F.R. Tongeren. 1995. Data Analysis in Community and Landscape Ecology. Cambridge University, Cambridge.Google Scholar
  36. Köppen, W. 1931. Grundriss der Klimakunde. Gruyter, Berlin.Google Scholar
  37. Kraft, N.J.B., R. Valencia and D.D. Ackerly. 2008. Functional traits and niche-based tree community assembly in an Amazonian forest. Science 332: 580–582.Google Scholar
  38. Lamb, E.G., S.W. Kembel and J.F. Cahill Jr. 2009. Biodiversity and ecosystem stability in a decade-long grassland experiment. J. Ecol. 97: 155–163.Google Scholar
  39. Lieberman, M. and D. Lieberman. 2007. Nearest-neighbor tree species combinations intropical forest: the role of chance, and some consequences of high diversity. Oikos 116: 377–386.Google Scholar
  40. Maestre, F.T., C. Escolar, I. Martínez and A. Escudero. 2008. Are soil lichen communities structured by biotic interactions? A null model analysis. J. Veg. Sci. 19: 261–266.Google Scholar
  41. Miranda, A.C., H.S. Miranda, I.O. Dias and B.F. Dias. 1993. Soil and air temperatures during prescribed Cerrado fires in central Brazil. J. Trop. Ecol. 9: 313–320.Google Scholar
  42. Moreira, A.G. 2000. Effects of fire protection on savanna structure in Central Brazil. J. Biogeogr. 27: 1021–1029.Google Scholar
  43. Mueller-Dombois, D. and H. Ellenberg. 1974. Aims and Methods of Vegetation Ecology. Wiley, New York.Google Scholar
  44. Navas, M.L. and J.M. Moreau-Richard. 2005. Can traits predict the competitive response of herbaceous Mediterranean species? Acta Oecol. 27: 107–114.Google Scholar
  45. Pausas, J.G. and M. Verdú. 2008. Fire reduces morphospace occupation in plant communities. Ecology 89: 2181–2186.PubMedGoogle Scholar
  46. Perry, G.L.W., N.J. Enright, B.P. Miller and B.B. Lamont. 2008. Spatial patterns in species-rich sclerophyll shrublands of southwestern Australia. J. Veg. Sci. 19: 705–716.Google Scholar
  47. Perry, G.L.W., N.J. Enright, B.P. Miller and B.B. Lamont. 2009. Nearest-neighbour interactions in species-rich shrublands: the roles of abundance, spatial patterns and resources. Oikos 118: 161–174.Google Scholar
  48. Ramos-Neto, M.B. and V.R. Pivello. 2000. Lightning fires in a Brazilian savanna National Park: rethinking management strategies. Environ. Manag. 26: 675–684.Google Scholar
  49. Rasband, W. 2004. ImageJ: Image Process and Analysis in Java. National Institute of Health, Bethesda.Google Scholar
  50. R Development Core Team 2009. R: A Language and Environment for sTatistical Computing. R Foundation for Statistical Computing, Vienna. URL Scholar
  51. San Jose, JJ., M.R. Farinas and J. Rosales. 1991. Spatial patterns of trees and structuring factors in a Trachypogon savanna of the Orinoco llanos. Biotropica 23: 114–123.Google Scholar
  52. Sarmiento, G. 1992. Adaptative strategies of perennial grasses in South America savannas. J. Veg. Sci. 3: 325–336.Google Scholar
  53. Silva, D.M. and M.A. Batalha. 2008. Soil–vegetation relationships in cerrados under different fire frequencies. Plant Soil 311: 87–96.Google Scholar
  54. Silva, I.A. and M.A. Batalha. 2010. Woody plant species co-occurrence in Brazilian savannas under different fire frequencies. Acta Oecol. 36: 85–91.Google Scholar
  55. Silva I.A, M.W. Valenti and D.M. Silva-Matos. 2009. Fire effects on the population structure of Zanthoxylum rhoifolium Lam (Ru-taceae) in a Brazilian savanna. Braz. J. Biol. 69: 631–637.Google Scholar
  56. Silva, J.F., A. Zambrano and M.R Fariñas. 2001. Increase in the woody component of seasonal savannas under different fire regimes in Calabozo, Venezuela. J. Biogeogr. 28: 977–983.Google Scholar
  57. Slingsby, J.A. and G.A.Verboom. 2006. Phylogenetic relatedness limits co-occurrence at fine spatial scales: evidence from the schoenoid sedges (Cyperaceae: Schoeneae)of the Cape Floristic Region, South Africa. Am. Nat. 168: 14–27.PubMedGoogle Scholar
  58. Stoll, P. and J. Weiner. 2000. A neighborhood view of interactions among individual plants. In: U. Dieckmann, R. Law and J. A. J. Metz (eds.), The Geometry of Ecological Interactions: Simplifying Spatial Complexity. Cambridge University Press, Cambridge, pp. 11–27.Google Scholar
  59. Stubbs, W.J. and B. Wilson. 2004. Evidence for limiting similarity in a sand dune community. J. Ecol. 92: 557–567.Google Scholar
  60. Syphard, A.D., J. Franklin and J.E. Keeley. 2006. Simulating the effects of frequent fire on southern California coastal shrublands. Ecol. Appl. 16: 744–1756.Google Scholar
  61. Unesco, United Nations Educational, Scientific, and Cultural Organization, 2001. Cerrado protected areas: Chapada dos Veadeiros and Emas National Parks. Unesco, Paris. URL Scholar
  62. Uriarte, M., R. Condit, C.D. Canham and S.P. Hubbell. 2004. A spatially explicit model of sapling growth in a tropical forest: does the identity of neighbours matter? J. Ecol. 92: 348–360.Google Scholar
  63. Verdú, M. and A. Valiente-Banuet. 2008. The nested assembly of plant facilitation networks prevents species extinctions. Am. Nat. 172: 751–760.PubMedGoogle Scholar
  64. Weiher, E. and P.A. Keddy. 1995. Assembly rules, null models, and trait dispersion: new questions from old patterns. Oikos 74: 159–164.Google Scholar
  65. Weiher, E., G.D.P. Clarke and P.A. Keddy. 1998. Community assembly rules, morphological dispersion, and the coexistence of plant species. Oikos 81: 309–322.Google Scholar
  66. Williams, R.J., G.D. Cook, A.M. Gill and P.H.R. Moore. 1999. Fire regime, fire intensity and tree survival in a tropical savanna in northern Australia. Aust. J. Ecol. 24: 50–59.Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest 2010

This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (, which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

Authors and Affiliations

  • I. A. Silva
    • 1
    Email author
  • G. H. Carvalho
    • 2
  • P. P. Loiola
    • 2
  • M. V. Cianciaruso
    • 3
  • M. A. Batalha
    • 2
  1. 1.Departamento de BotânicaUniversidade Federal de Săo CarlosSăo CarlosBrasil
  2. 2.Plant Ecology Laboratory, Department of BotanyFederal University of São CarlosSăo CarlosBrazil
  3. 3.Department of EcologyFederal University of GoiásGoiâniaBrazil

Personalised recommendations