Abstract
Invasive alien grasses can substantially alter fuel loads and fire regimes which could have significant consequences for fire-mediated nutrient losses. The effects of the alien grass Andropogon gayanus Kunth. (Gamba grass) on fire-mediated nutrient losses was evaluated in Australia’s tropical savannas. Losses of macronutrients during fire were determined by comparing the nutrient pools contained in the fine fuel before fire and in the ash after fire. Pre-fire grass nutrient pools were significantly higher in A. gayanus plots than in native grass plots for all nutrients measured (N, P, K, S, Ca, and Mg). Nutrient losses were substantially higher in A. gayanus plots, with 113% higher losses for N, 80% for P, 56% for K, 63 for S, 355% for Ca, and 345% for Mg. However, only losses of N and Mg varied significantly between grass types. A simplified savanna ecosystem nutrient budget estimated that A. gayanus fires led to the net N loss of 20 kg ha−1 y−1. This is a conservative estimate because total fuel loads were relatively low (7.85 t ha−1) for A. gayanus invaded plots leading to a relatively moderate intensity fire (6,408 kW m−1). Higher A. gayanus fuel loads and fire intensities could potentially lead to losses of up to 61.5 kg N ha−1 from the grass fuel. Over the long term, this is likely to lead to depletion of soil nutrients, particularly N, in the already low-fertility tropical savanna soils.
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References
Abbadie L. 2006. Nitrogen inputs to and outputs from the soil–plant system. In: Abbadie L, Gignoux J, Le Roux X, Lepage M, Eds. Lamto: Structure, Functioning and Dynamics of a Savanna Ecosystem. Springer: New York. pp 255–76
Aranibar JN, Macko SA, Andersen IC, Potgieter AIF, Sowry R, Shugart HH. 2003. Nutrient cycling responses to fire frequency in the Kruger National Park (South Africa) as indicated by stable isotope analysis. Isotopes Environ Health Stud 39:141–58
Asner GP, Beatty S. 1996. Effects of an African grass invasion on Hawaiian shrubland nitrogen biogeochemistry. Plant Soil 186:205–11
Beringer J, Packham D, Tapper N. 1995. Biomass burning and resulting emissions in the Northern Territory, Australia. Int J Wildl Fire 5:229–35
Bowman DMJS, Franklin DC, Price OF, Brook BW 2007. Land management affects grass biomass in the Eucalyptus tetrodonta savannas of monsoonal Australia. Austral Ecol 32:446–52
Brooks ML. 1999. Alien annual grasses and fire in the Mojave Desert. Madroño 46:13–9
Brooks ML, D’Antonio CM, Richardson DM, Grace JB, Keeley JE, DiTomaso JM, Hobbs RJ, Pellant M, Pyke D. 2004. Effects of invasive alien plants on fire regimes. BioScience 54:677–88
Byram GM. 1959. Combustion of forest fuels. In: Davies KP, Ed. Forest Fire Control and Use. McGraw-Hill: New York. pp 61–89
Chapin FSI, Matson PA, Mooney HA. 2002. Principles of Terrestrial Ecosystem Ecology. Springer-Verlag, New York
Cook BG, Pengelly BC, Brown SD, Donnelly JL, Eagles DA, Franco MA, Hanson J, Mullen BF, Partridge IJ, Peters M, Schultze-Kraft R. 2005. Tropical Forages: An Interactive Selection Tool, (CD-ROM). CSIRO, QLD DPI&F, CIAT and ILRI: Brisbane, Australia
Cook GD. 1994. The fate of nutrients during fires in a tropical savanna. Aust J Ecol 19:359–6
Cook GD. 2003. Fuel dynamics, nutrients, and atmospheric chemistry. In: Andersen AN, Cook G, Williams RJ, (eds) Fire in Tropical Savannas: the Kapalga Experiment. New York: Springer. pp 47–58
Crooks JA. 2002. Characterising ecosystem-level consequences of biological invasions: the role of ecosystem engineers. OIKOS 97:153–66
Crutzen PJ, Andreae MO. 1990. Biomass burning in the tropics: impact on atmospheric chemistry and biogeochemical cycles. Science 250:1669–78
D’Antonio, Hobbie SE. 2005. Plant species effects on ecosystem processes: insights from invasive species. In: Sax DF, Stachowicz JJ, Eds. Species Invasions. New York: Freeman. pp 65–84
D’Antonio CM. 2000. Fire, plant invasions and global change. In: Mooney HA, Hobbs RJ, Eds. Invasive Species in a Changing World. Island Press: Covelo, USA. pp 65–93
D’Antonio CM, Vitousek PM. 1992. Biological invasions by exotic grasses, the grass/fire cycle, and global change. Annu Rev Ecol Syst 23:63–87
Day KJ. 1977. Fertility studies on three red earth soils of the Daly basin, Northern Territory. Land Conservation Section, Animal Industry and Agriculture Branch, Department of the Northern Territory: Darwin
Day KJ, Harrison CJ, van Cuylenburg HRM. 1979. Land resources of Wildman River Station, N.T. Land Conservation Unit, Territory Parks and Wildlife Commission, Darwin
Edwards A, Hauser P, Anderson M, McCartney J, Armstrong M, Thackway R, Allan G, Hempel C, Russell-Smith JS. 2001. A tale of two parks: contemporary fire regimes of Litchfield and Nitmiluk National Parks, monsoonal northern Australia. Int J Wildl Fire 10:79–89
Grace J, San Jose J, Meir P, Miranda HS, Montes RA. 2006. Productivity and carbon fluxes of tropical savannas. J Biogeogr 33:387–400
Grigulis K, Lavorel S, Davies ID, Dossantos A, Llorets F, Villa M. 2005. Landscape-scale positive feedbacks between fire and expansion of the large tussock grass, Ampelodesmos mauritanica in Catalan shrublands. Glob Chang Biol 11:11042–53
Hurst DF, Griffith DWT, Cook GD. 1994. Trace gas emissions from biomass burning in tropical Australian savannas. J Geophys Res 99:3619–34
Hutley LB, Setterfield SA. in press 2008. Savannas. In: Jørgensen SE, Fath B, (eds) Encyclopedia of Ecology. Amsterdam: Elsevier
Isbell RF. 1996. The Australian Soil Classification. CSIRO Publishing, Collingwood, Vic
Keith H. 1997. Nutrient cycling in eucalypt ecosystems. In: Williams JE, Woinarski JCZ, Eds. Eucalypt Ecology: Individuals to Ecosystems. Cambridge University Press: Cambridge. pp 197–226
Kondo Y, Takegawa N, Miyazaki Y, Ko M, Koike M, Kita K, Kawakami S, Shirai T, Ogawa T, Blake DR, Liley B, Russell J. 2003. Effects of biomass burning and lightning on atmospheric chemistry over Australia and South-east Asia. Int J Wildl Fire 12:271–81
Laclau J, Sama-Poumba W, de Dieu Nzila J, Bouillet J, Ranger J. 2002. Biomass and nutrient dynamics in a littoral savanna subjected to annual fires in Congo. Acta Ecol 23:41–50
Langkamp PJ, Swinden LB, Dalling MH. 1979. Nitrogen fixation (acetylene reduction) by Acacia pellita on areas restored after mining at Groote Eylandt, Northern Territory. Aust J Bot 27:353–61
Levine JA, Villa M, D’Antonio CM, Dukes JS, Grigulis K, Lavorel S. 2003. Mechanisms underlying the impacts of exotic plant invasions. Proc Roy Soc Lond 270:775–81
Mack MC, D’Antonio CM, Ley RE. 2001. Alteration of ecosystem nitrogen dynamics by exotic plants: a case study of C4 grasses in Hawaii. Ecol Appl 11:1323–35
McNaughton SJ, Stronach NRH, Georgiadis NJ. 1998. Combustion in natural fires and global emissions budgets. Ecol Appl 8:464–8
Medina E. 1982. Nitrogen balance in the Trachypogon grasslands of Central Venezuela. Plant Soil 67:305–14
Mistry J. 2000. World savannas: ecology and human use. London: Prentice Hall
Moore PHR, Gill AM, Kohnert R. 1995. Quantifying bushfires for ecology using two electronic devices and biological indicators. CALMSci Suppl 4:83–7
Mott JJ, Williams J, Andrew MH, Gillison AN. 1985. Australian savanna ecosystems. In: Tothill JC, Mott JJ, Eds. Ecology and Management of the World’s Savannas. Commonwealth Agricultural Bureau: Brisbane. pp 56–82
National Greenhouse Gas Inventory Committee 2006. National Greenhouse Gas Inventory 2004. Australian Greenhouse Office: Canberra
Noller BN, Currey NA, Cusbert PJ, Tuor M, Bradley P, Harrison A. 1985. Temporal varability in atmospheric nutrient flux to the Magela and Nourlangie Creek system of the Northern Territory. Proc Ecol Soc Aust 13:21–31
Oesterheld M, Loreti J, Semmartin M, Paruelo JM. 1999. Grazing, fire, and climate effects on primary productivity of grasslands and savannas. In: Walker LR, Ed. Ecosystems of Disturbed Ground. Elsevier: Amsterdam. pp 287–306
Pivello VR, Coutinho LM. 1992. Transfer of macro-nutrients to the atmosphere during experimental burnings in an open Cerrado (Brazilian savanna). J Trop Ecol 8:487–97
Raison RJ, Connell MJ, Khanna PK, Keith H. 1993. Effects of repeated fires on nitrogen and phosphorus budgets and cycling processes in forest ecosystems. In: Trabaud L, Prodon R, Eds. Fire in Mediterranean Ecosystems. Commission of the European Communities: Brussels. pp 347–63
Raison RJ, Khanna PK, Woods PV. 1985. Mechanisms of element transfer to the atmosphere during vegetation fires. Can J For Res 15:132–40
Richardson DM, Pysek P, Rejmanek M, Barbour MG, Panetta FD, West CJ. 2000. Naturalization and invasion of alien plants: concepts and definitions. Divers Distrib 6:93–107
Rose D. 2006. The Dynamics of Coarse Woody Debris in the Mesic Tropical Savanna of the Darwin Region: Abundance, Decomposition and Consumption by Fire. Charles Darwin University
Rossiter-Rachor NA, Setterfield SA, Douglas MM, Hutley LB, Cook GD, Schmidt S. submitted. Invasive Andropogon gayanus (gamba grass) is an ecosystem transformer of nitrogen relations in tropical savanna. Submitted to Ecology
Rossiter NA, Setterfield SA, Douglas MM, Hutley LB. 2003. Testing the grass-fire cycle: alien grass invasion in the tropical savannas of northern Australia. Divers Distrib 9:169–76
Rossiter NA, Setterfield SA, Douglas MM, Hutley LB, Cook G. 2004. Exotic grass invasion in the tropical savannas of northern Australia: ecosystem consequences. In: Sindel BM, Johnson SB, Eds. Proceedings of the 14th Australian Weeds Conference: Weeds Society of New South Wales, Sydney. pp 168–71
Russell-Smith J, Ryan PG, Durieu R. 1997. A LANDSAT MSS-derived fire history of Kakadu National Park, monsoonal northern Australia, 1980–94: seasonal extent, frequency and patchiness. J Appl Ecol 34:748–66
Schmidt S, Lamble RE. 2002. Does clearing of woody vegetation result in sustainable pastures? Considerations for nutrient dynamics Rangel J 24:96–111
Scholes RJ, Walker BH. 1993. An African Savannas: Synthesis of the Nylsvley Study. Cambridge University Press, Cambridge
Simberloff D. 1981. Community effects of introduced species. In: Nitecki MH, Ed. Biotic Crises in Ecological and Evolutionary Time. New York: Academic Press. pp 53–71
Strayer DL, Eviner VT, Jeschke JM, Pace ML. 2006. Understanding the long-term effects of species invasions. Trends Ecol Evol 21:645–51
Sturman A, Tapper N. 2006. The Weather and Climate of Australia and New Zealand. Oxford, Melbourne
Tothill JC, Nix HA, Stanton JP, Russell MJ. 1985. Land Use and Productive Potential of Australian Savanna Lands. Ecology and Management of the World’s Savannas. Australian Academy of Science: Canberra. pp 125–41
Walker BH. 1985. Determinants of Tropical Savannas. ICSU Press, Florida
Williams DG, Baruch Z. 2000. African grass invasion in the Americas: ecosystem consequences and the role of ecophysiology. Biol Invasions 2:123–40
Williams RJ, Cook GD, Gill AM, Moore PHR. 1999. Fire regime, fire intensity and tree survival in a tropical savanna in northern Australia. Int J Wildl Fire 8:227–39
Williams RJ, Gill AM, Moore PHR. 1998. Seasonal changes in fire behaviour in a tropical savanna in northern Australia. Int J Wildl Fire 8:227–39
Acknowledgements
We gratefully acknowledge the Parks and Wildlife Commission of the Northern Territory (PWCNT) for access to field sites, and the rangers at Wildman Reserve, particularly A. Anderson and P. Ross for conducting the controlled fuel-reduction burns. We also thank the Bushfires NT, in particular J. Whatley, S. Lamb and L. Humphris, for their advice on study sites at Adelaide River and additional information about the wildfire. G. Quinn (Deakin University) and K. McGuinness (Charles Darwin University) provided much appreciated advice on the study design and statistical analysis. We also gratefully acknowledge J. Barratt, N. Hewitt-Ware, A. Raith, B. Ryan and M. Thiele, for field and lab assistance. Nutrient analyses were carried out by the University of Queensland, School of Land, Crop and Food Sciences. Z. Baruch, A. Andersen and two anonymous reviewers provided valuable comments on the draft manuscript. Charles Darwin University, CSIRO and the Tropical Savannas Management CRC provided N. Rossiter-Rachor with PhD funding to undertake the project.
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Rossiter-Rachor, N.A., Setterfield, S.A., Douglas, M.M. et al. Andropogon gayanus (Gamba Grass) Invasion Increases Fire-mediated Nitrogen Losses in the Tropical Savannas of Northern Australia. Ecosystems 11, 77–88 (2008). https://doi.org/10.1007/s10021-007-9108-x
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DOI: https://doi.org/10.1007/s10021-007-9108-x