Ecological thresholds at the savanna-forest boundary: How plant traits, resources and fire govern the distribution of tropical biomes

Ecology Letters

Volumn 15, Issue 7, 2012, Pages 759-768

  Hoffmann, William A ^a   Geiger, Erika L ^a,c   Gotsch, Sybil G ^a,d   Rossatto, Davi R ^b   Silva, Lucas C R ^b,e   Lau, On Lee ^a,f   Haridasan, M ^b   Franco, Augusto C ^b  

^a NORTH CAROLINA STATE UNIVERSITY   (United States)

^b UNIVERSITY OF BRASILIA   (Brazil)

^c Canyonlands Research Station   (United States)

^d UNIVERSITY OF NEW HAMPSHIRE   (United States)

^e UNIVERSITY OF CALIFORNIA   (United States)

^f National Park Service Academy Program   (United States)

Author keywords

Alternate stable states; Critical thresholds; Forest; Savanna; Tipping point

Indexed keywords

BARK; BIOME; CANOPY ARCHITECTURE; ECOZONE; ENVIRONMENTAL CONDITIONS; FOREST FIRE; GRASS; GROWTH RATE; POPULATION DISTRIBUTION; RESOURCE AVAILABILITY; SAVANNA; THRESHOLD;

BRAZIL;

EID: 85027922178     PISSN: 1461023X     EISSN: 14610248     Source Type: Journal    
DOI: 10.1111/j.1461-0248.2012.01789.x     Document Type: Article

References (100)

1. Amorim, K. & Batalha, A. (2007). Soil-vegetation relationships in hyperseasonal cerrado, seasonal cerrado, and wet grassland in Emas National Park (central Brazil). Acta Oecol., 32, 319-327.
2. Archibald, S., Roy, D.P., van Wilgen, B.W. & Scholes, R.J. (2009). What limits fire? An examination of drivers of burnt area in Southern Africa. Glob. Change Biol., 15, 613-630.
3. Archibald, S., Nickless, A., Govender, N., Scholes, R.J. & Lehsten, V. (2010). Climate and the inter-annual variability of fire in southern Africa: a meta-analysis using long-term field data and satellite-derived burnt area data. Glob. Ecol. Biogeogr., 19, 794-809.
4. Arora, V.K. & Boer, G.J. (2005). Fire as an interactive component of dynamic vegetation models. J. Geophys. Res.-Biogeosci., 110, DOI: 10.1029/2005JG000042.
5. Asner, G.P., Levick, S.R., Kennedy-Bow n, T., Knapp, D.E., Emerson, R., Jacobson, J. et al. (2009). Large-scale impacts of herbivores on the structural diversity of African savannas. Proc. Natl. Acad. Sci. USA, 106, 4947-4952.
6. Balch, J.K., Nepstad, D.C., Curran, L.M., Brando, P.M., Portela, O., Guilherme, P. et al. (2011). Size, species, and fire behavior predict tree and liana mortality from experimental burns in the Brazilian Amazon. For. Ecol. Manag., 261, 68-77.
7. Barbosa, R.I. & Fearnside, P.M. (2005). Fire frequency and area burned in the Roraima savannas of Brazilian Amazonia. For. Ecol. Manag., 204, 371-384.
8. Barlow, J. & Peres, C.A. (2008). Fire-mediated dieback and compositional cascade in an Amazonian forest. Philos. Trans. R. Soc. B-Biol. Sci., 363, 1787-1794.
9. Beckage, B., Platt, W.J. & Gross, L.J. (2009). Vegetation, fire, and feedbacks: a disturbance-mediated model of savannas. Am. Nat., 174, 805-818.
10. Bell, R.H.V. (1984). Notes on elephant-woodland interactions. In: Status and Conservation of Africa's Elephants and Rhinos (ed. Cumming, D.H.M.). IUCN, Gland, Switzerland, pp. 98-103.
11. Biddulph, J. & Kellman, M. (1998). Fuels and fire at savanna gallery forest boundaries in southeastern Venezuela. J. Trop. Ecol., 14, 445-461.
12. 4 grasslands and savannas? Annu. Rev. Ecol. Evol. Syst., 39, 641-659.
13. Bond, W.J. (2010). Do nutrient-poor soils inhibit development of forests? A nutrient stock analysis. Plant Soil, 334, 47-60.
14. 2-controlled mechanism of woody plant invasion in grasslands and savannas. Glob. Change Biol., 6, 865-969.
15. Bond, W.J. & Midgley, J.J. (2001). Ecology of sprouting in woody plants: the persistence niche. Trends Ecol. Evol., 16, 45-51.
16. Bond, W.J., Woodward, F.I. & Midgley, G.F. (2005). The global distribution of ecosystems in a world without fire. New Phytol., 165, 525-537.
17. Bowman, D.M.J.S. (1993). Establishment of two dry monsoon forest species on a fire-protected monsoon forest-savanna boundary, Cobourg Peninsula, northern Australia. Aust. J. Ecol., 18, 235-237.
18. Bowman, D.M.J.S. (2000). Australian Rainforests: Islands of Green in a Land of Fire. Cambridge University Press, Cambridge.
19. Bowman, D.M.J.S. & Fensham, R.J. (1991). Response of a monsoon forest-savanna boundary to fire protection, Weipa, northern Australia. Aust. J. Ecol., 16, 111-118.
20. Bowman, D.M.J.S., Walsh, A. & Milne, D.J. (2001). Forest expansion and grassland contraction within a Eucalyptus savanna matrix between 1941 and 1994 at Litchfield National Park in the Australian National Park in the Australian monsoon tropics. Glob. Ecol. Biogeogr., 10, 535-548.
21. Brando, P.M., Nepstad, D.C., Balch, J.K., Bolker, B., Christman, M.C., Coe, M. et al. (2012). Fire-induced tree mortality in a neotropical forest: the roles of bark traits, tree size, wood density and fire behavior. Glob. Change Biol., 18, 630-641.
22. Cochrane, M.A. & Schulze, M.D. (1999). Fire as a recurrent event in tropical forests of the eastern Amazon: effects on forest structure, biomass, and species composition. Biotropica, 31, 2-16.
23. Collin, A., Bernardin, D. & Sero-Guillaume, O. (2011). A physical-based cellular automaton model for forest-fire propagation. Combust. Sci. Technol., 183, 347-369.
24. Coutinho, L.M. (1990) Fire in the ecology of the Brazilian Cerrado. In: Fire in the Tropical Biota (ed. Goldhammer, J.G.). Springer Verlag, Berlin, pp. 82-105.
25. Durigan, G. & Ratter, J.A. (2006). Successional changes in cerrado and cerrado/forest ecotonal vegetation in western Sao Paulo State, Brazil, 1962-2000. Edinb. J. Bot., 63, 119-130.
26. Durigan, G., Nishikawa, D.L.L., Rocha, E., Silveira, É.R.d., Pulitano, F.M., Regalado, L.B. et al. (2002). Caracterização de dois estratos da vegetação em uma área de Cerrado. Acta Bot. Bras., 16, 251-262.
27. Eldridge, D.J., Bowker, M.A., Maestre, F.T., Roger, E., Reynolds, J.F. & Whitford, W.G. (2011). Impacts of shrub encroachment on ecosystem structure and functioning: towards a global synthesis. Ecol. Lett., 14, 709-722.
28. Fensham, R.J., Fairfax, R.J., Butler, D.W. & Bowman, D.M.J.S. (2003). Effects of fire and drought in a tropical eucalypt savanna colonized by rain forest. J. Biogeogr., 30, 1405-1414.
29. Fensham, R., Fairfax, R. & Ward, D. (2009). Drought-induced tree death in savanna. Glob. Change Biol., 15, 380-387.
30. Gardner, T.A. (2006). Tree-grass coexistence in the Brazilian cerrado: demographic consequences of environmental instability. J. Biogeogr., 33, 448-463.
31. Geiger, E.L., Gotsch, S.G., do Vale, G.D., Haridasan, M., Franco, A.C. & Hoffmann, W.A. (2011). Distinct roles of savanna and forest tree species in regeneration following fire suppression in a Brazilian savanna. J. Veg. Sci., 22, 312-321.
32. Gignoux, J., Clobert, J. & Menaut, J.-C. (1997). Alternative fire resistance strategies in savanna trees. Oecologia, 110, 576-583.
33. Gignoux, J., Lahoreau, G., Julliard, R. & Barot, S. (2009). Establishment and early persistence of tree seedlings in an annually burned savanna. J. Ecol., 97, 484-495.
34. Good, S.P. & Caylor, K.K. (2011). Climatological determinants of woody cover in Africa. Proc. Natl. Acad. Sci. USA, 108, 4902-4907.
35. Gotsch, S.G., Geiger, E.L., Franco, A.C., Goldstein, G., Meinzer, F.C. & Hoffmann, W.A. (2010). Allocation to leaf area and sapwood area affects water relations of co-occurring savanna and forest trees. Oecologia, 163, 291-301.
36. Govender, N., Trollope, W.S.W. & Van Wilgen, B.W. (2006). The effect of fire season, fire frequency, rainfall and management on fire intensity in savanna vegetation in South Africa. J. Appl. Ecol., 43, 748-758.
37. Groffman, P., Baron, J., Blett, T., Gold, A., Goodman, I., Gunderson, L. et al. (2006). Ecological thresholds: the key to successful environmental management or an important concept with no practical application? Ecosystems, 9, 1-13.
38. Hanan, N.P., Sea, W.B., Dangelmayr, G. & Govender, N. (2008). Do fires in savannas consume woody biomass? A comment on approaches to modeling savanna dynamics. Am. Nat., 171, 851-856.
39. Haridasan, M. (1992). Observations on soils, foliar nutrient concentrations and floristic composition of cerrado sensu stricto and cerradão communities in central Brazil. In: Nature and Dynamics of Forest-Savanna Boundaries (eds Furley, P.A., Proctor, J. & Ratter, J.A.) Chapman & Hall, London, pp. 171-184.
40. Hennenberg, K.J., Goetze, D., Minden, V., Traore, D. & Porembski, S. (2005). Size-class distribution of Anogeissus leiocarpus (Combretaceae) along forest-savanna ecotones in northern Ivory Coast. J. Trop. Ecol., 21, 273-281.
41. Hennenberg, K.J., Fischer, F., Kouadio, K., Goetze, D., Orthmann, B., Linsenmair, K.E. et al. (2006). Phytomass and fire occurrence along forest-savanna transects in the Comoe National Park, Ivory Coast. J. Trop. Ecol., 22, 303-311.
42. Higgins, S.I., Bond, W.J. & Trollope, W.S.W. (2000). Fire, resprouting and variability: a recipe for grass-tree coexistence in savanna. J. Ecol., 88, 213-229.
43. Higgins, S.I., Bond, W.J., February, E.C., Bronn, A., Euston-Brown, D.I.W., Enslin, B. et al. (2007). Effects of four decades of fire manipulation on woody vegetation structure in savanna. Ecology, 88, 1119-1125.
44. Hirota, M., Nobre, C., Oyama, M.D. & Bustamante, M.M.C. (2010). The climatic sensitivity of the forest, savanna and forest-savanna transition in tropical South America. New Phytol., 187, 707-719.
45. Hirota, M., Holmgren, M., Van Nes, E.H. & Scheffer, M. (2011). Global resilience of tropical forest and savanna to critical transitions. Science, 334, 232-235.
46. Hoffmann, W.A. (1998). Post-burn reproduction of woody plants in a neotropical savanna: the relative importance of sexual and vegetative reproduction. J. Appl. Ecol., 35, 422-433.
47. Hoffmann, W.A. (1999). Fire frequency and population dynamics of woody plants in a neotropical savanna. Ecology, 80, 1354-1369.
48. Hoffmann, W.A. (2000). Post-establishment seedling success in the Brazilian cerrado: a comparison of savanna and forest species. Biotropica, 32, 62-69.
49. Hoffmann, W.A. & Franco, A.C. (2003). Comparative growth analysis of tropical forest and savanna woody plants using phylogenetically-independent contrasts. J. Ecol., 91, 475-484.
50. Hoffmann, W.A. & Solbrig, O.T. (2003). The role of topkill in the differential response of savanna woody plants to fire. For. Ecol. Manag., 180, 273-286.
51. Hoffmann, W.A., Orthen, B. & Nascimento, P.K.V. (2003). Comparative fire ecology of tropical savanna and forest trees. Funct. Ecol., 17, 720-726.
52. Hoffmann, W.A., Orthen, B. & Franco, A.C. (2004). Constraints to seedling success of savanna and forest trees across the savanna-forest boundary. Oecologia, 140, 252-260.
53. Hoffmann, W.A., da Silva, E.R., Machado, G.C., Bucci, S.J., Scholz, F.G., Goldstein, G. et al. (2005). Seasonal leaf dynamics across a tree density gradient in a Brazilian savanna. Oecologia, 145, 307-316.
54. Hoffmann, W.A., Adasme, R., Haridasan, M., Carvalho, M., Geiger, E.L., Pereira, M.A.B. et al. (2009). Tree topkill, not mortality, governs the dynamics of alternate stable states at savanna-forest boundaries under frequent fire in central Brazil. Ecology, 90, 1326-1337.
55. Hoffmann, W.A., Jaconis, S.Y., McKinley, K.L., Geiger, E.L., Gotsch, S.G. & Franco, A.C. (2011). Fuels or microclimate? Understanding the drivers of fire feedbacks at savanna-forest boundaries. Austral. Ecol., DOI: 10.1111/j.1442-9993.2011.02324.x.
56. Holdo, R.M. (2005). Stem mortality following fire in Kalahari sand vegetation: effects of frost, prior damage, and tree neighbourhoods. Plant Ecol., 180, 77-86.
57. Holdo, R.M., Holt, R.D. & Fryxell, J.M. (2009). Grazers, browsers, and fire influence the extent and spatial pattern of tree cover in the Serengeti. Ecol. Appl., 19, 95-109.
58. Hopkins, B. (1992). Ecological processes at the forest-savanna boundary. In: Nature and Dynamics of the Forest-Savanna Boundaries (eds Furley, P.A., Procter, J. & Ratter, J.A.). Chapman and Hall, London, pp. 21-33.
59. Hopkins, B. & Jenkin, R.N. (1962). Vegetation of the Olokemeji Forest Reserve, Nigeria I. General features and the research sites. J. Ecol., 50, 559-598.
60. Johnson, N.L., Kotz, S. & Kemp, A.W. (1992). Univariate Discrete Distributions. John Wiley and Sons, New York.
61. Kellman, M. (1984). Synergistic relationships between fire and low soil fertility in neotropical savannas: a hypothesis. Biotropica, 16, 158-160.
62. Lau, O.L. (2009). Evolution of tree architecture in the Brazilian Cerrado. Master's Thesis. North Carolina State University, Raleigh, p. 55.
63. Lawes, M.J., Adie, H., Russell-Smith, J., Murphy, B. & Midgley, J.J. (2011a) How do small savanna trees avoid stem mortality by fire? The roles of stem diameter, height and bark thickness. Ecosphere, 2, DOI:10.1890/ES10-00204.1.
64. Lawes, M.J., Richards, A., Dathe, J. & Midgley, J.J. (2011b). Bark thickness determines fire resistance of selected tree species from fire-prone tropical savanna in north Australia. Ecol. Plant, 212, 2057-2069.
65. Lehmann, C.E.R., Archibald, S.A., Hoffmann, W.A. & Bond, W.J. (2011). Deciphering the distribution of the savanna biome. Phytol. New, 191, 197-209.
66. Lindenmayer, D.B., Hobbs, R.J., Likens, G.E., Krebs, C.J. & Banks, S.C. (2011). Newly discovered landscape traps produce regime shifts in wet forests. Proc. Sci. Natl. Acad. USA, 108, 15887-15891.
67. Loudermilk, E.L., Cropper, W.P., Mitchell, R.J. & Lee, H. (2011). Longleaf pine (Pinus palustris) & hardwood dynamics in a fire-maintained ecosystem: a simulation approach. Model. Ecol., 222, 2733-2750.
68. McCarthy, M.A., Gill, A.M. & Bradstock, R.A. (2001). Theoretical fire-interval distributions. Int. J. Wildland Fire., 10, 73-77.
69. Midgley, J.J., Lawes, M.J. & Chamaille-Jammes, S. (2010). Savanna woody plant dynamics: the role of fire & herbivory, separately & synergistically. Aust. J. Bot., 58, 1-11.
70. Pinheiro, M.H.O. & Monteiro, R. (2006). Contribution of forest species to the floristic composition of a forested savanna in Southeastern Brazil. Braz. Arch. Biol. Technol., 49, 763-774.
71. Pinheiro, M.H.O., de Azevedo, T.S. & Monteiro, R. (2010). Spatial-temporal distribution of fire-protected savanna physiognomies in Southeastern Brazil. Bras. An. Acad. Cienc., 82, 379-395.
72. Prior, L.D., Williams, R.J. & Bowman, D. (2010) Experimental evidence that fire causes a tree recruitment bottleneck in an Australian tropical savanna. J. Trop. Ecol., 26, 595-603
73. Pueyo, S., Graca, P.M.D., Barbosa, R.I., Cots, R., Cardona, E. & Fearnside, P.M. (2011). Testing for criticality in ecosystem dynamics: the case of Amazonian rainforest and savanna fire. Ecol. Lett., 13, 793-802.
74. Ramos-Neto, M.B. & Pivello, V.R. (2000). Lightning fires in a Brazilian savanna national park: rethinking management strategies. Environ. Manag., 26, 675-684.
75. Ratnam, J., Bond, W.J., Fensham, R.J., Hoffmann, W.A., Archibald, S., Lehmann, C.E.R. et al. (2011). When is a 'forest' a savanna, and why does it matter? Glob. Ecol. Biogeogr., 20, 653-660.
76. Ratter, J.A. (1992). Transitions between cerrado and forest vegetation in Brazil. In: Nature and Dynamics of Forest-Savanna Boundaries (eds Furley, P.A., Procter, J. & Ratter, J.A.). Chapman & Hall, London, pp. 417-429.
77. Ray, D., Nepstad, D. & Moutinho, P. (2005). Micrometeorological and canopy controls of fire susceptibility in a forested Amazon landscape. Ecol. Appl., 15, 1664-1678.
78. Rossatto, D.R., Hoffmann, W.A. & Franco, A.C. (2009). Differences in growth patterns between co-occurring forest and savanna trees affect the forest-savanna boundary. Funct. Ecol., 23, 689-698.
79. Ruggiero, P.G.C., Batalha, M.A., Pivello, V.R. & Meirelles, S.T. (2002). Soil-vegetation relationships in cerrado (Brazilian savanna) and semideciduous forest, Southeastern Brazil. Plant Ecol., 160, 1-16.
80. Russell-Smith, J. (2004). Rain forest invasion of eucalypt-dominated woodland savanna, iron range, north-eastern Australia: I. Successional processes. J. Biogeogr., 31, 1293-1303.
81. Russell-Smith, J., Yates, C.P., Whitehead, P.J., Smith, R., Craig, R., Allan, G.E. et al. (2007). Bushfires 'down under': patterns and implications of contemporary Australian landscape burning. Int. J. Wildland Fire, 16, 361-377.
82. Russell-Smith, J., Yates, C.P., Brock, C. & Westcott, V.C. (2010). Fire regimes and interval-sensitive vegetation in semiarid Gregory National Park, northern Australia. Aust. J. Bot., 58, 300-317.
83. Ryan, C.M. & Williams, M. (2011). How does fire intensity and frequency affect miombo woodland tree populations and biomass? Ecol. Appl., 21, 48-60.
84. San José, J.J. & Fariñas, M.R. (1991). Temporal changes in the structure of a Trachypogon savanna protected for 25 years. Acta Oecol., 12, 237-247.
85. Sankaran, M., Hanan, N.P., Scholes, R.J., Ratnam, J., Augustine, D.J., Cade, B.S. et al. (2005). Determinants of woody cover in African savannas. Nature, 438, 846-849.
86. Scheiter, S. & Higgins, S.I. (2009). Impacts of climate change on the vegetation of Africa: an adaptive dynamic vegetation modelling approach. Glob. Change Biol., 15, 2224-2246.
87. Silva, L.C.R., Sternberg, L., Haridasan, M., Hoffmann, W.A., Miralles-Wilhelm, F. & Franco, A.C. (2008). Expansion of gallery forests into central Brazilian savannas. Glob. Change Biol., 14, 2108-2118.
88. Silva, L.C.R., Haridasan, M., Sternberg, L.S.L., Franco, A.C. & Hoffmann, W.A. (2010). Not all forests are expanding over central Brazilian savannas. Plant Soil, 333, 431-442.
89. Staver, A.C., Archibald, S. & Levin, S. (2011a). Tree cover in sub-Saharan Africa: rainfall and fire constrain forest and savanna as alternative stable states. Ecology, 92, 1063-1072.
90. Staver, A.C., Archibald, S. & Levin, S.A. (2011b). The global extent and determinants of savanna and forest as alternative biome states. Science, 334, 230-232.
91. Stevens, J.T. & Beckage, B. (2009). Fire feedbacks facilitate invasion of pine savannas by Brazilian pepper (Schinus terebinthifolius). New Phytol., 184, 365-375.
92. Swaine, M.D., Hawthorne, W.D. & Orgle, T.K. (1992). The effects of fire exclusion on savanna vegetation at Kpong, Ghana. Biotropica, 24, 166-172.
93. Thonicke, K., Venevsky, S., Sitch, S. & Cramer, W. (2001). The role of fire disturbance for global vegetation dynamics: coupling fire into a Dynamic Global Vegetation Model. Glob. Ecol. Biogeogr., 10, 661-677.
94. Tinley, K.L. (1982). The influence of soil moisture balance on ecosystem patterns in southern Africa. In: Ecology of Tropical Savannas (eds Huntley, B.J. & Walker, B.H.). Springer-Verlag, Berlin, pp. 175-192.
95. Uhl, C. & Kauffman, J.B. (1990). Deforestation, fire susceptibility and potential tree responses to fire in the eastern Amazon. Ecology, 71, 437-449.
96. Wakeling, J.L., Staver, A.C. & Bond, W.J. (2011). Simply the best: the transition of savanna saplings to trees. Oikos, 120, 1448-1451.
97. Warman, L. & Moles, A.T. (2009). Alternative stable states in Australia's Wet Tropics: a theoretical framework for the field data and a field-case for the theory. Landsc. Ecol., 24, 1-13.
98. Williams, R.J., Cook, G.D., Gill, A.M. & Moore, P.H.R. (1999). Fire regime, fire intensity and tree survival in a tropical savanna in northern Australia. Aust. J. Ecol., 24, 50-59.
99. Wilson, J.B. & Agnew, A.D.Q. (1992). Positive-feedback switches in plant communities. Adv. Ecol. Res., 23, 263-335.
100. Wood, S.W. & Bowman, D.M.J.S. (2012). Alternative stable states and the role of fire-vegetation-soil feedbacks in the temperate wilderness of southwest Tasmania. Landsc. Ecol., 27, 13-28.