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RESEARCH ARTICLE
Contents Vol 58(7)

Effects of soil temperature regimes after fire on seed dormancy and germination in six Australian Fabaceae species

Victor M. Santana A F , Ross A. Bradstock B , Mark K. J. Ooi C D , Andrew J. Denham C , Tony D. Auld C and M. Jaime Baeza A E
+ Author Affiliations
- Author Affiliations

A Fundación de la Generalitat Valenciana Centro de Estudios Ambientales del Mediterráneo (CEAM), Parque Tecnológico Paterna, C/Charles Darwin, 14. 46980 Valencia, Spain.

B Centre for Environmental Risk Management of Bushfires, Institute for Conservation Biology and Environmental Management, University of Wollongong, NSW 2522, Australia.

C Department of Environment, Climate Change and Water NSW, PO Box 1967, Hurstville, NSW 2220, Australia.

D Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK.

E Departamento de Ecología, Universidad de Alicante, Ap 99. 03080 Alicante, Spain.

F Corresponding author. Email: vm.santana@ua.es

Australian Journal of Botany 58(7) 539-545 https://doi.org/10.1071/BT10144
Submitted: 4 June 2010  Accepted: 18 August 2010   Published: 27 October 2010

Abstract

In addition to direct fire cues such as heat, smoke and charred wood, the passage of fire leads indirectly to changes in environmental conditions which may be able to break physical dormancy in hard-coated seeds. After a fire, the open canopy and the burnt material lying on the surface alter the thermal properties of the soil, resulting in elevated soil temperatures for long periods of time. We simulated daily temperature regimes experienced at different depths of soil profile after a summer fire. Our aim was to determine whether these temperature regimes and the duration of exposure (5, 15 and 30 days) play an important role breaking physical seed dormancy in six legumes from south-eastern Australia. Our results showed that simulated temperature regimes break seed dormancy. This effect is specially pronounced at temperatures that are expected to occur near the soil surface (0–2 cm depth). The duration of exposure interacts with temperature to break dormancy, with the highest germination rates reached after the longest duration and highest temperatures. However, the germination response varied among species. Therefore, this indirect post-fire cue could play a role in the regeneration of plant communities, and could stimulate seedling emergence independent of direct fire cues as well as in interaction with direct cues.


Acknowledgements

We thank Fiona Thomson for providing seeds for this experiment. V. M. Santana was supported by a FPU grant awarded by the Spanish Ministry of Education and Science and by the Consolider-Ingenio 2010 (GRACCIE CSD2007–00067) and FIREMED (AGL2008–04522/FOR) projects. CEAM is supported by the Generalitat Valenciana and Fundación Bancaja.


References


Auld TD (1986) Population dynamics of the shrub Acacia suaveolens (Sm.) Willd.: fire and the transition to seedlings. Australian Journal of Ecology 11, 373–385.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Auld TD, Bradstock RA (1996) Soil temperatures after the passage of a fire: do they influence the germination of buried seeds? Australian Journal of Ecology 21, 106–109.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Auld TD, Denham AJ (2006) How much seed remains in the soil after a fire? Plant Ecology 187, 15–24.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Auld TD, O’Connell MA (1991) Predicting patterns of post-fire germination in 35 eastern Australian Fabaceae. Australian Journal of Ecology 16, 53–70.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Baeza MJ, Roy J (2008) Germination of an obligate seeder (Ulex parviflorus) and consequences for wildfire management. Forest Ecology and Management 256, 685–693.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Baeza MJ, Vallejo VR (2006) Ecological mechanisms involved in dormancy breakage in Ulex parviflorus seeds. Plant Ecology 183, 191–205.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Bell DT (1999) Turner Review No. 1. The process of germination in Australian species. Australian Journal of Botany 47, 475–517.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Bradstock RA, Auld TD (1995) Soil temperatures during experimental bushfires in relation to fire intensity: consequences for legume germination and fire management in south-eastern Australia. Journal of Applied Ecology 32, 76–84.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Bradstock RA, Bedward M (1992) Simulation of the effect of season of fire on post-fire seedling emergence of two Banksia species based on long-term rainfall records. Australian Journal of Botany 40, 75–88.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Brown NAC (1993) Promotion of germination of fynbos seeds by plant-derived smoke. New Phytologist 123, 575–583.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Carrington ME (1999) Post-fire seedling establishment in Florida sand pine scrub. Journal of Vegetation Science 10, 403–412.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Carrington ME, Keeley JE (1999) Comparison of post-fire seedling establishment between scrub communities in mediterranean and non-mediterranean climate ecosystems. Journal of Ecology 87, 1025–1036.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Cocks MP, Stock WD (1997) Heat stimulated germination in relation to seed characteristics in fynbos legumes of the Western Cape Province, South Africa. South African Journal of Botany 63, 129–132. open url image1

CSIRO (2007) ‘Climate change in Australia.’ Technical Report 2007. (CSIRO Publishing: Melbourne)

De Luis M, Raventos J, Gonzalez-Hidalgo JC (2005) Fire and torrential rainfall: effects on seedling establishment in Mediterranean gorse shrublands. International Journal of Wildland Fire 14, 413–422.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Dixon KW, Roche S, Pate JS (1995) The promotive effect of smoke derived from burnt native vegetation on seed germination of Western Australian plants. Oecologia 101, 185–192.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Frazer JM, Davis SD (1988) Differential survival of chaparral seedlings during the first summer drought after wildfire. Oecologia 76, 215–221.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Hagon MW (1971) The action of temperature fluctuations on hard seeds of subterranean clover. Australian Journal of Experimental Agriculture 11, 440–443.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Hodgkinson KC (1991) Shrub recruitment response to intensity and season of fire in a semi-arid woodland. Journal of Applied Ecology 28, 60–70.
| Crossref | GoogleScholarGoogle Scholar | open url image1

IPCC (2007) Climatic Change, 2007. Synthesis Report. An assessment of the Intergovernmental Panel on Climate Change, Geneva.

Ivens GW (1983) The influence of temperature on germination of gorse (Ulex europaeus L.). Weed Research 23, 207–216.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Keeley J (1991) Seed germination and life history syndromes in the California chaparral. The Botanical Review 57, 81–116.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Keeley JE (1987) Role of fire in seed germination of woody taxa in California chaparral. Ecology 68, 434–443.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Keeley JE, Fotheringham CJ (1998) Smoke-induced seed germination in California chaparral. Ecology 79, 2320–2336.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Keith DA (1997) Combined effects of heat shock, smoke and darkness on germination of Epacris stuartii Stapf., an endangered fire-prone Australian shrub. Oecologia 112, 340–344.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Kruger FJ , Bigalke RC (1984) Fire in fynbos. In ‘Ecological effects of fire in south African ecosystems’. (Eds P de Van Booysen, NM Tainton) pp. 69–94. (Springer-Verlag: Berlin)

Lonsdale WM (1993) Losses from the seed bank of Mimosa pigra: soil micro-organisms vs. temperature fluctuations. Journal of Applied Ecology 30, 654–660.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Monk D, Pate JS, Loneragan WA (1981) Biology of Acacia pulchella R.Br. with special reference to symbiotic nitrogen fixation. Australian Journal of Botany 29, 579–592.
| Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

Moreira B, Tormo J, Estrelles E, Pausas JG (2010) Disentangling the role of heat and smoke as germination cues in Mediterranean Basin flora. Annals of Botany 105, 627–635.
| Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | open url image1

Morris EC (2000) Germination response of seven east Australian Grevillea species (Proteaceae) to smoke, heat exposure and scarification. Australian Journal of Botany 48, 179–189.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Ooi MKJ (2007) Dormancy classification and potential dormancy-breaking cues for shrub species from fire-prone south-eastern Australia. In ‘Seeds: biology, development and ecology’. (Eds SW Adkins, S Ashmore, SC Navie) pp. 205–216. (CAB International: Wallingford, UK)

Ooi MKJ, Auld TD, Denham AJ (2009) Cimate change and bet-hedging: interactions between increased soil temperatures and seed bank persistence. Global Change Biology 15, 2375–2386.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Paula S, Pausas JG (2008) Burning seeds: germinative response to heat treatments in relation to resprouting ability. Journal of Ecology 96, 543–552.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Raison RJ, Woods PV, Jakobsen BF, Bary GAV (1986) Soil temperatures during and following low-intensity prescribed burning in a Eucalyptus pauciflora forest. Australian Journal of Soil Research 24, 33–47.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Sharrow SH, Wright HA (1977) Effects of fire, ash, and litter on soil nitrate, temperature, moisture and tobosa grass production in the Rolling Plains. Journal of Range Management 30, 266–270.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Taylor GB (1981) Effect of constant temperature treatments followed by fluctuating temperatures on the softening of hard seeds of Trifolium subterraneum L. Australian Journal of Plant Physiology 8, 547–558.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Thomas PB, Morris EC, Auld TD (2003) Interactive effects of heat shock and smoke on germination of nine species forming soil seed banks within the Sydney region. Austral Ecology 28, 674–683.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Trabaud L (1994) Postfire plant community dynamics in the Mediterranean basin. In ‘The role of fire in Mediterranean-type ecosystems’. (Eds JM Moreno, WC Oechel) pp. 1–15. (Springer-Verlag: New York)

Tyler CM (1995) Factors contributing to postfire seedling establishment in chaparral: direct and indirect effects of fire. Journal of Ecology 83, 1009–1020.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Van Assche JA, Debucquoy KLA, Rommens WAF (2003) Seasonal cycles in the germination capacity of buried seeds of some Leguminoseae (Fabaceae). New Phytologist 158, 315–323.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Van Staden J, Brown NAC, Jäger AK, Jonson TA (2000) Smoke as germination cue. Plant Species Biology 15, 167–178.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Walker J , Raison RJ , Khanna PK (1986) Fire. In ‘Australian soils: the human impact’. (Eds JS Russell, RF Isbell) pp. 185–216. (University of Queensland Press: Brisbane)

Whight S, Bradstock RA (1999) Indices of fire characteristics in sandstone heath near Sydney, Australia. International Journal of Wildland Fire 9, 145–153.
| Crossref | GoogleScholarGoogle Scholar | open url image1