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The impact of increased temperatures on germination patterns of semi-aquatic plants

Published online by Cambridge University Press:  02 October 2019

Jade Dessent
Affiliation:
School of Life Sciences, La Trobe University, Wodonga, Victoria, Australia
Susan Lawler
Affiliation:
School of Life Sciences, La Trobe University, Wodonga, Victoria, Australia
Daryl Nielsen*
Affiliation:
CSIRO Land and Water, Thurgoona, NSW, Australia Centre for Freshwater Ecosystems, Latrobe University, Wodonga, Victoria, Australia
*
Author for correspondence: Daryl Nielsen, E-mail: [email protected]

Abstract

Future climate change predictions indicate that there will be an increase in ambient air temperature. Increases in ambient air temperature will result in a corresponding increase in soil temperature. The consequences of further increases in soil temperature will potentially be detrimental for the soil seed bank of plants in terms of length of dormancy and viability of seeds. This experiment investigated the effect of different exposure temperatures and duration of exposure on the germination of semi-aquatic plant species. Seeds of four species (Alternanthera denticulata, Juncus usitatus, Persicaria lapathifolia and Persicaria prostrata) were exposed to temperatures ranging from 25 to 100°C for durations between 1 and 14 days, before being germinated in an incubator for 6 weeks. Germination occurred in all four species after exposure to temperatures ranging from 25 to 60°C. These temperatures appeared to promote germination as the temperature and duration of exposure increased. However, in P. lapathifolia and P. prostrata, the number of seeds germinating declined when exposed to 70°C and there was no germination for temperatures exceeding this. In contrast, A. denticulata and J. usitatus only began to decline when exposed to 80°C, with no germination at higher temperatures. These results suggest that soil temperatures exceeding potential threshold temperatures of 70 and 80°C will result in a decline in the number of seeds germinating and may potentially see a change in species distributions. As such soil temperatures are already being experienced throughout Australia, some species may already be close to their thermal threshold.

Type
Research Paper
Copyright
Copyright © Cambridge University Press 2019 

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References

Auld, TD and Bradstock, RA (1996) Soil temperatures after the passage of a fire: do they influence the germination of buried seeds? Australian Journal of Ecology 21, 106109.Google Scholar
Baskin, CC and Baskin, JM (2001) Seeds: Ecology, Biogeography and Evolution of Dormancy and Germination. Cambridge, UK: Cambridge University Press.Google Scholar
Baskin, CC, Thompson, K and Baskin, JM (2006) Mistakes in germination ecology and how to avoid them. Seed Science Research 16, 165168.Google Scholar
Baskin, JM and Baskin, CC (2004) A classification system for seed dormancy. Seed Science Research 14, 116.Google Scholar
Baskin, JM, Davis, BH, Baskin, CC, Gleason, SM and Cordell, S (2004) Physical dormancy in seeds of Dodonaea viscosa (Sapindales, Sapindaceae) from Hawaii. Seed Science Research 14, 8190.Google Scholar
Bradstock, R and Auld, T (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, 7684.Google Scholar
Brändel, M (2004) The role of temperature in the regulation of dormancy and germination of two related summer-annual mudflat species. Aquatic Botany 79, 1532.Google Scholar
Brock, MA, Nielsen, DL, Shiel, RJ, Green, JD and Langley, JD (2003) Drought and aquatic community resilience: the role of eggs and seeds in sediments of temporary wetlands. Freshwater Biology 48, 12071218.Google Scholar
Campbell, C and Nielsen, D (2014) Maintenance of plant biodiversity by riverine corridors, pp. 51–68 in The Role of Hydrological and Riparian Connectivity in Maintaining Biodiversity of River-Floodplain Ecosystems. Final Report prepared for Department of Environment's National Environmental Research Program by the MDFRC and CSIRO, MDFRC Publication 38/2014, April, 245 pp.Google Scholar
Cottrell, HJ (1948) Tetrazolium salt as a seed germination indicator. Annals of Applied Biology 35, 123131.Google Scholar
CSIRO (2007) Climate Change in Australia. Canberra, Australia: CSIRO.Google Scholar
Dexter, BD (1970) Regeneration of river redgum Eucalyptus camaldulensis Dehn. Melbourne University.Google Scholar
Dunlop, M and Brown, PR (2008) Implication of climate change for Australia's national reserve system: a preliminary assessment. Canberra, Department of Climate Change and the Department of the Environment, Water, Heritage and the Arts.Google Scholar
Durant, RA, Nielsen, DL and Ward, KA (2016) Evaluation of Pseudoraphis spinescens (Poaceae) seed bank from Barmah Forest floodplain. Australian Journal of Botany 64, 669677.Google Scholar
Figuerola, J and Green, AJ (2002) Dispersal of aquatic organisms by waterbirds: a review of past research and priorities for future studies. Freshwater Biology 47, 483494.Google Scholar
Finch-Savage, WE and Leubner-Metzger, G (2006) Seed dormancy and the control of germination. New Phytologist 171, 501523.Google Scholar
Gleadow, RM and Narayan, I (2007) Temperature thresholds for germination and survival of Pittosporum undulatum: implications for management by fire. Acta Oecologica 31, 151157.Google Scholar
Gleason, RA, Euliss, NHJ, Hubbard, DE and Duffy, WG (2003) Effects of sediment load on emergence of aquatic invertebrates and plants from wetland soil egg and seed banks. Wetlands 23, 2634.Google Scholar
Harte, J, Torn, MS, Chang, F-R, Feifarek, B, Kinzig, AP, Shaw, R and Shen, K (1995) Global warming and soil microclimate: results from a meadow-warming experiment. Ecological Applications 5, 132150.Google Scholar
Hughes, L (2003) Climate change and Australia: trends, projections and impacts. Austral Ecology 28, 423443.Google Scholar
Hughes, L (2011) Climate change and Australia: key vulnerable regions. Regional Environmental Change 11, 189195.Google Scholar
IPCC (2014) Climate Change 2014: Synthesis Report. Contribution of Working Groups I, II and III to the Fifth Assessment Report of the intergovernmental panel on Climate Change. IPCC, Geneva, Switzerland.Google Scholar
Keeley, JE and Fotheringham, C (2000) Role of fire in regeneration from seed, pp. 311330 in Fenner, M (ed), Seeds: The Ecology of Regeneration in Plant Communities, Wallingford, UK: CAB International.Google Scholar
Leck, MA and Simpson, RL (1987) Seed bank of a freshwater tidal wetland: turnover and relationship to vegetation change. American Journal of Botany 74, 360370.Google Scholar
Long, RL, Gorecki, MJ, Renton, M, Scott, JK, Colville, L, Goggin, DE, Commander, LE, Westcott, DA, Cherry, H and Finch-Savage, WE (2015) The ecophysiology of seed persistence: a mechanistic view of the journey to germination or demise. Biological Reviews 90, 3159.Google Scholar
McKenney, DW, Pedlar, JH, Lawrence, K, Campbell, K and Hutchinson, MF (2007) Potential impacts of climate change on the distribution of North American trees. BioScience 57, 939948.Google Scholar
Mott, J (1972) Germination studies on some annual species from an arid region of Western Australia. Journal of Ecology 60, 293304.Google Scholar
Nicholson, A and Keddy, PA (1983) The depth profile of a shoreline seed bank in Matchedash Lake, Ontario. Canadian Journal of Botany 61, 32933296.Google Scholar
Nielsen, D, Campbell, C, Rees, G, Durant, R, Littler, R and Petrie, R (2018) Seed bank dynamics in wetland complexes associated with a lowland river. Aquatic Sciences 80, 23.Google Scholar
Nielsen, DL and Brock, MA (2009) Modified water regime and salinity as a consequence of climate change: prospects for wetlands of Southern Australia. Climatic Change 95, 523533.Google Scholar
Nielsen, DL, Jasper, EW, Ning, N and Lawler, S (2015) High sediment temperatures influence the emergence of dormant aquatic biota. Marine and Freshwater Research 66, 11381146.Google Scholar
Nielsen, DL, Podnar, K, Watts, RJ and Wilson, AL (2013) Empirical evidence linking increased hydrologic stability with decreased biotic diversity within wetlands. Hydrobiologia 708, 8196.Google Scholar
Ooi, MK, Denham, AJ, Santana, VM and Auld, TD (2014) Temperature thresholds of physically dormant seeds and plant functional response to fire: variation among species and relative impact of climate change. Ecology and Evolution 4, 656671.Google Scholar
Ooi, MKJ, Auld, TD and Denham, AJ (2009) Climate change and bet-hedging: interactions between increased soil temperatures and seed bank persistence. Global Change Biology 15, 23752386.Google Scholar
Ooi, MKJ, Auld, TD and Denham, AJ (2012) Projected soil temperature increase and seed dormancy response along an altitudinal gradient: implications for seed bank persistence under climate change. Plant and Soil 353, 289303.Google Scholar
Pinceel, T, Buschke, F, Weckx, M, Brendonck, L and Vanschoenwinkel, B (2018) Climate change jeopardizes the persistence of freshwater zooplankton by reducing both habitat suitability and demographic resilience. BMC Ecology 18, 2.Google Scholar
Qiu, J, Bai, Y, Fu, Y-B and Wilmshurst, JF (2010) Spatial variation in temperature thresholds during seed germination of remnant Festuca hallii populations across the Canadian prairie. Environmental and Experimental Botany 67, 479486.Google Scholar
Santana, VM, Bradstock, RA, Ooi, MKJ, Denham, AJ, Auld, TD and Baeza, MJ (2010) Effects of soil temperature regimes after fire on seed dormancy and germination in six Australian Fabaceae species. Australian Journal of Botany 58, 539545.Google Scholar
Sheldon, KS, Yang, S and Tewksbury, JJ (2011) Climate change and community disassembly: impacts of warming on tropical and temperate montane community structure. Ecology Letters 14, 11911200.Google Scholar
Smith, DW (2007) The effects of fire on a wetland plant seeds and zooplankton eggs in Barren Box Swamp, NSW. Latrobe University.Google Scholar
Soons, MB (2006) Wind dispersal in freshwater wetlands: knowledge for conservation and restoration. Applied Vegetation Science 9, 271278.Google Scholar
Soons, MB and Ozinga, WA (2005) How important is long-distance seed dispersal for the regional survival of plant species? Diversity & Distributions 11, 165172.Google Scholar
Steadman, KJ and Pritchard, HW (2004) Germination of Aesculus hippocastanum seeds following cold-induced dormancy loss can be described in relation to a temperature-dependent reduction in base temperature (Tb) and thermal time. New Phytologist 161, 415425.Google Scholar
Suppiah, R, Hennessy, KJ, Whetton, PH, McInnes, K, Macadam, I, Bathols, J and Ricketts, J (2007) Australian climate change projections derived from simulations performed for the IPCC 4th Assessment Report. Australian Meteorological Magazine 56, 131152.Google Scholar
Thuiller, W, Lavorel, S, Araújo, MB, Sykes, MT and Prentice, IC (2005) Climate change threats to plant diversity in Europe. Proceedings of the National Academy of Sciences of the USA 102, 82458250.Google Scholar
van Der Valk, AG and Davis, CB (1979) A reconstruction of the recent vegetational history of a prairie marsh, Eagle Lake, Iowa, from its seed bank. Aquatic Botany 6, 2951.Google Scholar
Walck, JL, Hidayati, SN, Dixon, KW, Thompson, K and Poschlod, P (2011) Climate change and plant regeneration from seed. Global Change Biology 17, 21452161.Google Scholar
Warton, DI and Hui, FK (2011) The arcsine is asinine: the analysis of proportions in ecology. Ecology 92, 310.Google Scholar