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dc.contributor.authorBowman, DMJS
dc.contributor.authorMacDermott, HJ
dc.contributor.authorNichols, SC
dc.contributor.authorMurphy, BP
dc.date.accessioned2020-12-22T04:53:37Z
dc.date.available2020-12-22T04:53:37Z
dc.date.issued2014-11-01
dc.identifier.citationBowman, D. M. J. S., MacDermott, H. J., Nichols, S. C. & Murphy, B. P. (2014). A grass-fire cycle eliminates an obligate-seeding tree in a tropical savanna. ECOLOGY AND EVOLUTION, 4 (21), pp.4185-4194. https://doi.org/10.1002/ece3.1285.
dc.identifier.issn2045-7758
dc.identifier.urihttp://hdl.handle.net/11343/258164
dc.description.abstractA grass-fire cycle in Australian tropical savannas has been postulated as driving the regional decline of the obligate-seeding conifer Callitris intratropica and other fire-sensitive components of the regional flora and fauna, due to proliferation of flammable native grasses. We tested the hypothesis that a high-biomass invasive savanna grass drives a positive feedback process where intense fires destroy fire-sensitive trees, and the reduction in canopy cover facilitates further invasion by grass. We undertook an observational and experimental study using, as a model system, a plantation of C. intratropica that has been invaded by an African grass, gamba (Andropogon gayanus) in the Northern Territory, Australia. We found that high grass biomass was associated with reduced canopy cover and restriction of foliage to the upper canopy of surviving stems, and mortality of adult trees was very high (>50%) even in areas with low fuel loads (1 t·ha(-1)). Experimental fires, with fuel loads >10 t·ha(-1), typical of the grass-invasion front, caused significant mortality due to complete crown scorch. Lower fuel loads cause reduced canopy cover through defoliation of the lower canopy. These results help explain how increases in grass biomass are coupled with the decline of C. intratropica throughout northern Australia by causing a switch from litter and sparse perennial grass fuels, and hence low-intensity surface fires, to heavy annual grass fuel loads that sustain fires that burn into the midstorey. This study demonstrates that changes in fuel type can alter fire regimes with substantial knock-on effects on the biota.
dc.languageEnglish
dc.publisherWILEY
dc.titleA grass-fire cycle eliminates an obligate-seeding tree in a tropical savanna
dc.typeJournal Article
dc.identifier.doi10.1002/ece3.1285
melbourne.affiliation.departmentUniversity General
melbourne.affiliation.departmentSchool of Geography
melbourne.source.titleEcology and Evolution
melbourne.source.volume4
melbourne.source.issue21
melbourne.source.pages4185-4194
dc.rights.licenseCC BY
melbourne.elementsid1031559
melbourne.contributor.authorNichols, Scott
melbourne.contributor.authorMurphy, Brett
dc.identifier.eissn2045-7758
melbourne.accessrightsOpen Access


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