Species mixture effects on flammability across plant phylogeny: the importance of litter particle size and the special role for non-Pinus Pinaceae

Abstract

Fire affects and is affected by plants. Vegetation varies in flammability, that is, its general ability to burn, at different levels of ecological organization. To scale from individual plant traits to community flammability states, understanding trait effects on species flammability variation and their interaction is important. Plant traits are the cumulative result of evolution and they show, to differing extents, phylogenetic conservatism. We asked whether phylogenetic distance between species predicts species mixture effects on litterbed flammability. We conducted controlled laboratory burns for 34 phylogenetically wide-ranging species and 34 random two-species mixtures from them. Generally, phylogenetic distance did not predict species mixture effects on flammability. Across the plant phylogeny, most species were flammable except those in the non-Pinus Pinaceae, which shed small needles producing dense, poorly ventilated litterbeds above the packing threshold and therefore nonflammable. Consistently, either positive or negative dominance effects on flammability of certain flammable or those non-flammable species were found in mixtures involving the non-Pinus Pinaceae. We demonstrate litter particle size is key to explaining species nonadditivity in fuelbed flammability. The potential of certain species to influence fire disproportionately to their abundance might increase the positive feedback effects of plant flammability on community flammability state if flammable species are favored by fire.

References van Altena, C., van Logtestijn, R. S. P., Cornwell, W. K., & Cornelissen, J. H. C. (2012). Species composition and fire: Non-additive mixture effects on ground fuel flammability. Frontiers in Plant Science, 3, 63. Anderson, H. (1970). Forest fuel ignitibility. Fire Technology, 6, 312–319. Balbi, J., Santoni, P., & Dupuy, J. (1999). Dynamic modelling of fire spread across a fuel bed. International Journal of Wildland Fire, 9, 275–284. Banwell, E. M., & Varner, J. M. (2014). Structure and composition of forest floor fuels in long-unburned Jeffrey pine–white fir forests of the Lake Tahoe Basin, USA. International Journal of Wildland Fire, 23, 363–372. Baum, D. A. (2008). Trait evolution on a phylogenetic tree: Relatedness, similarity, and the myth of evolutionary advancement. Nature Education, 1, 1. Baum, D. A., Smith, S. D., & Donovan, S. S. S. (2005). Evolution – The tree-thinking challenge. Science, 310, 979–980. Belcher, C. M. (2016). The influence of leaf morphology on litter flammability and its utility for interpreting palaeofire. Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences, 371, 20150163. Blauw, L. G., Wensink, N., Bakker, L., van Logtestijn, R. S. P., Aerts, R., Soudzilovskaia, N. A., & Cornelissen, J. H. C. (2015). Fuel moisture content enhances nonadditive effects of plant mixtures on flammability and fire behavior. Ecology and Evolution, 5, 3830–3841. Bond, W. J. (2005). Large parts of the world are brown or black: A different view on the ‘Green World’ hypothesis. Journal of Vegetation Science, 16, 261–266. Bond, W. J., & Keeley, J. E. (2005). Fire as a global ‘herbivore’: The ecology and evolution of flammable ecosystems. Trends in Ecology & Evolution, 20, 387–394. Bradstock, R. A., Gill, A. M., & Williams, R. J. (2012). Flammable Australia: Fire regimes, biodiversity and ecosystems in a changing world. Collingwood, Australia: CSIRO PUBLISHING. Cadotte, M., Albert, C. H., & Walker, S. C. (2013). The ecology of differences: Assessing community assembly with trait and evolutionary distances. Ecology Letters, 16, 1234–1244. Conard, S. G., & Ivanova, G. A. (1997). Wildfire in Russian boreal forests - Potential impacts of fire regime characteristics on emissions and global carbon balance estimates. Environmental Pollution, 98, 305–313. Cornelissen, J. H. C., Lavorel, S., Garnier, E., Diaz, S., Buchmann, N., Gurvich, D. E., Reich, P. B., ter Steege, H., Morgan, H. D., van der Heijden, M. G. A., Pausas, J. G., & Pooter, H. (2003). A handbook of protocols for standardised and easy measurement of plant functional traits worldwide. Australian Journal of Botany, 51, 335–380. Cornwell, W. K., Elvira, A., van Kempen, L., van Logtestijn, R. S. P., Aptroot, A., & Cornelissen, J. H. C. (2015). Flammability across the gymnosperm phylogeny: The importance of litter particle size. New Phytologist, 206, 672–681. Curt, T., Schaffhauser, A., Borgniet, L., Dumas, C., Esteve, R., Ganteaume, A., Jappiot, M., Martin, W., N'Diaye, A., & Poilvet, B. (2011). Litter flammability in oak woodlands and shrublands of southeastern France. Forest Ecology and Management, 261, 2214–2222. Dale, V. H., Joyce, L. A., McNulty, S., Neilson, R. P., Ayres, M. P., Flannigan, M. D., … & Peterson, C. J. (2001). Climate change and forest disturbances: Climate change can affect forests by altering the frequency, intensity, duration, and timing of fire, drought, introduced species, insect and pathogen outbreaks, hurricanes, windstorms, ice storms, or landslides. BioScience, 51, 723–734. D'Antonio, C. M., & Vitousek, P. M. (1992). Biological invasions by exotic grasses, the grass/fire cycle, and global change. Annual Review of Ecology and Systematics, 23, 63–87. Intergovernmental Panel on Climate Change (2014). Climate change 2014-Impacts, Adaptation and Vulnerability: Regional Aspects. Cambridge, United Kingdom: Cambridge University Press. Flannigan, M. D., Krawchuk, M. A., de Groot, W. J., Wotton, B. M., & Gowman, L. M. (2009b). Implications of changing climate for global wildland fire. International Journal of Wildland Fire, 18, 483–507. Flannigan, M., Stocks, B., Turetsky, M., & Wotton, M. (2009a). Impacts of climate change on fire activity and fire management in the circumboreal forest. Global Change Biology, 15, 549–560. Fonda, R.W., Belanger, L.A., & Burley, L.L. (1998). Burning characteristics of western conifer needles. Northwest Science, 72, 1–9. Harden, J., Trumbore, S., Stocks, B., Hirsch, A., Gower, S., O'neill, K., & Kasischke, E. (2000). The role of fire in the boreal carbon budget. Global Change Biology, 6, 174–184. He, T., Belcher, C. M., Lamont, B. B., & Lim, S. L. (2016). A 350-million-year legacy of fire adaptation among conifers. Journal of Ecology, 104, 352–363. He, T. H., Pausas, J. G., Belcher, C. M., Schwilk, D. W., & Lamont, B. B. (2012). Fire-adapted traits of Pinus arose in the fiery Cretaceous. New Phytologist, 194, 751–759. Kane, J. M., Varner, J. M., & Hiers, J. K. (2008). The burning characteristics of southeastern oaks: Discriminating fire facilitators from fire impeders. Forest Ecology and Management, 256, 2039–2045. Kasischke, E. S., Christensen, N. L., & Stocks, B. J. (1995). Fire, global warming, and the carbon balance of boreal forests. Ecological Applications, 5, 437–451. Keeley, J. E., Pausas, J. G., Rundel, P. W., Bond, W. J., & Bradstock, R. A. (2011). Fire as an evolutionary pressure shaping plant traits. Trends in Plant Science, 16, 406–411. de Magalhaes, R. M. Q., & Schwilk, D. W. (2012). Leaf traits and litter flammability: Evidence for non-additive mixture effects in a temperate forest. Journal of Ecology, 100, 1153–1163. Morvan, D., & Dupuy, J. (2001). Modeling of fire spread through a forest fuel bed using a multiphase formulation. Combustion and Flame, 127, 1981–1994. Morvan, D., & Larini, M. (2001). Modeling of one dimensional fire spread in pine needles with opposing air flow. Combustion Science and Technology, 164, 37–64. Morvan, D., Méradji, S., & Accary, G. (2009). Physical modelling of fire spread in grasslands. Fire Safety Journal, 44, 50–61. O'Donnell, J. A., Turetsky, M. R., Harden, J. W., Manies, K. L., Pruett, L. E., Shetler, G., & Neff, J. C. (2009). Interactive effects of fire, soil climate, and moss on CO₂ fluxes in black spruce ecosystems of interior Alaska. Ecosystems, 12, 57–72. Page, S. E., Siegert, F., Rieley, J. O., Boehm, H. D. V., Jaya, A., & Limin, S. (2002). The amount of carbon released from peat and forest fires in Indonesia during 1997. Nature, 420, 61–65. Papió, C., & Trabaud, L. (1990). Structural characteristics of fuel components of five Mediterranean shrubs. Forest Ecology and Management, 35, 249–259. Parsons, A. L., Balch, J. K., de Andrade, R. B., & Brando, P. M. (2015). The role of leaf traits in determining litter flammability of south-eastern Amazon tree species. International Journal of Wildland Fire, 24, 1143–1153. Pausas, J. G., & Keeley, J. E. (2009). A burning story: The role of fire in the history of life. BioScience, 59, 593–601. Pausas, J. G., & Moreira, B. (2012). Flammability as a biological concept. New Phytologist, 194, 610–613. Plucinski, M. P., & Anderson, W. R. (2008). Laboratory determination of factors influencing successful point ignition in the litter layer of shrubland vegetation. International Journal of Wildland Fire, 17, 628–637. Prinzing, A., Durka, W., Klotz, S., & Brandl, R. (2001). The niche of higher plants: Evidence for phylogenetic conservatism. Proceedings of the Royal Society B-Biological Sciences, 268, 2383–2389. R Core Team. (2013). R: A Language and Environment for Statistical Computing. Vienna, Austria: R Foundation for Statistical Computing. Rothermel, R. C. (1972). A mathematical model for predicting fire spread in wildland fuels. Utah, United States: USDA Forest Service. Scarff, F. R., & Westoby, M. (2006). Leaf litter flammability in some semi-arid Australian woodlands. Functional Ecology, 20, 745–752. Schwilk, D. W. (2015). Dimensions of plant flammability. New Phytologist, 206, 486–488. Schwilk, D. W., & Ackerly, D. D. (2001). Flammability and serotiny as strategies: Correlated evolution in pines. Oikos, 94, 326–336. Schwilk, D. W., & Caprio, A. C. (2011). Scaling from leaf traits to fire behaviour: Community composition predicts fire severity in a temperate forest. Journal of Ecology, 99, 970–980. Stephens, S. L., Finney, M. A., & Schantz, H. (2004). Bulk density and fuel loads of ponderosa pine and white fir forest floors: Impacts of leaf morphology. Northwest Science, 78, 93–110. Viegas, D. X. (1998). Forest fire propagation. Philosophical Transactions-Mathematical Physical and Engineering Sciences, 356, 2907–2928. Weber, R. (1991). Modelling fire spread through fuel beds. Progress in Energy and Combustion Science, 17, 67–82. Wyse, S. V., Perry, G. L., O'Connell, D. M., Holland, P. S., Wright, M. J., Hosted, C. L., … & Curran, T. J. (2016). A quantitative assessment of shoot flammability for 60 tree and shrub species supports rankings based on expert opinion. International journal of Wildland Fire, 25, 466–477. Zanne, A. E., Tank, D. C., Cornwell, W. K., Eastman, J. M., Smith, S. A., FitzJohn, R. G., McGlinn, D. J., O'Meara, B. C., Moles, A. T., Reich, P. B., et al. (2014). Three keys to the radiation of angiosperms into freezing environments. Nature, 506, 89–92. Zhao, W., Blauw, L. G., van Logtestijn, R. S., Cornwell, W. K., & Cornelissen, J. H. (2014). Interactions between fine wood decomposition and flammability. Forests, 5, 827–846.