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Seed size, shape and persistence in the soil in an Iranian flora

Published online by Cambridge University Press:  22 February 2007

Ken Thompson*
Affiliation:
Department of Animal and Plant Sciences, The University, Sheffield S10 2TN, UK
Adel Jalili
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
John G. Hodgson
Affiliation:
Department of Animal and Plant Sciences, The University, Sheffield S10 2TN, UK
Behnam Hamzeh'ee
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Younes Asri
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Sue Shaw
Affiliation:
Department of Animal and Plant Sciences, The University, Sheffield S10 2TN, UK
Anoushiravan Shirvany
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Shahbaz Yazdani
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Mostafa Khoshnevis
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Fatemeh Zarrinkamar
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Mohammad-Ali Ghahramani
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
Reza Safavi
Affiliation:
Department of Research Institute of Forests and Rangelands, PO Box 13185-116, Tehran, Iran
*
*Correspondence Fax: +44 (0) 114 2220015 Email: ken.thompson@sheffield.ac.uk

Abstract

Previous studies on several floras have shown that species with small, rounded seeds tend to accumulate persistent seed banks in the soil, while species with larger, less compact seeds do not. The suggested underlying mechanism is predation. Small seeds experience less predation and are more likely to become buried, which itself offers significant protection from predation by vertebrates. The relationship between seed size and shape and persistence in the soil was examined for the flora of the Arasbaran Protected Area in northwest Iran. Seed size was related to persistence in the soil in Iran in the same way as in most other floras examined, but seed shape was not. It is suggested that predation prevents persistence of large seeds in most floras. Where large-seeded persistent species predominate, for example in Australia and (to a lesser extent) in New Zealand, other factors may interfere with the relationship between seed size and predation.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2001

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References

Assadi, M. (1987) Plants of Arasbaran protected Area, NW Iran. Part I. Iran Journal of Botany 3, 129175.Google Scholar
Assadi, M. (1988) Plants of Arasbaran protected Area, NW Iran. Part II. Iran Journal of Botany 4, 159.Google Scholar
Bekker, R.M., Bakker, J.P., Grandin, U., Kalamees, R., Milberg, P., Poschlod, P., Thompson, K. and Willems, J.H. (1998) Seed size, shape and vertical distribution in the soil: indicators of seed longevity. Functional Ecology 12, 834842.CrossRefGoogle Scholar
Funes, G., Basconcelo, S., Diaz, S. and Cabido, M. (1999) Seed size and shape are good predictors of seed persistence in soil in temperate mountain grasslands of Argentina. Seed Science Research 9, 341345.CrossRefGoogle Scholar
Hulme, P.E. (1994) Post-dispersal seed predation in grassland – Its magnitude and sources of variation. Journal of Ecology 82, 645652.CrossRefGoogle Scholar
Hulme, P.E. (1998a) Post-dispersal seed predation and seed bank persistence. Seed Science Research 8, 513519.CrossRefGoogle Scholar
Hulme, P.E. (1998b) Post-dispersal seed predation: consequences for plant demography and evolution. Perspectives in Plant Ecology, Evolution and Systematics 1, 3246.CrossRefGoogle Scholar
Ireland, C. and Andrew, M.H. (1995) Ants remove virtually all western myall (Acacia papyrocarpa Benth) seeds at Middleback, South Australia. Australian Journal of Ecology 20, 565570.CrossRefGoogle Scholar
Kyereh, B., Swaine, M.D. and Thompson, J. (1999) Effect of light on the germination of forest trees in Ghana. Journal of Ecology 87, 772783.CrossRefGoogle Scholar
Leck, M.A. (1989) Wetland seed banks. pp. 283305in Leck, M.A.; Parker, V.T.; Simpson, R.L. (Eds) Ecology of soil seed banks. San Diego, Academic Press.CrossRefGoogle Scholar
Leishman, M.R. and Westoby, M. (1998) Seed size and shape are not related to persistence in soil in Australia in the same way as in Britain. Functional Ecology 12, 480485.CrossRefGoogle Scholar
Milberg, P., Andersson, L. and Thompson, K. (2000) Large-seeded species are less dependent on light for germination than small-seeded ones. Seed Science Research 10, 99104.CrossRefGoogle Scholar
Moles, A.T. and Drake, D.R. (1999) Post-dispersal seed predation on eleven large-seeded species from the New Zealand flora: a preliminary study in secondary forest. New Zealand Journal of Botany 37, 679685.CrossRefGoogle Scholar
Moles, A.T., Hodson, D.W. and Webb, C.J. (2000) Seed size and shape and persistence in the soil in the New Zealand flora. Oikos 89, 541545.CrossRefGoogle Scholar
Peart, M.H. (1984) The effects of morphology, orientation and position of grass diaspores on seedling survival. Journal of Ecology 72, 437453.CrossRefGoogle Scholar
Predavec, M. (1997) Seed removal by rodents, ants and birds in the Simpson Desert, central Australia. Journal of Arid Environments 36, 327332.CrossRefGoogle Scholar
Price, M.V. and Joyner, J.W. (1997) What resources are available to desert granivores: seed rain or soil seed bank? Ecology 78, 764773.Google Scholar
Rechinger, K.H. (1963) Flora Iranica. Graz, Akademische Druck- u. Verlagsanstalt.Google Scholar
Thompson, K. (1987) Seeds and seed banks. New Phytologist 106 (suppl.), 2334.CrossRefGoogle Scholar
Thompson, K. and Grime, J.P. (1979) Seasonal variation in the seed banks of herbaceous species in ten contrasting habitats. Journal of Ecology 67, 893921.CrossRefGoogle Scholar
Thompson, K., Band, S.R. and Hodgson, J.G. (1993) Seed size and shape predict persistence in the soil. Functional Ecology 7, 236241.CrossRefGoogle Scholar
Thompson, K., Green, A. and Jewels, A.M. (1994) Seeds in soil and worm casts from a neutral grassland. Functional Ecology 8, 2935.CrossRefGoogle Scholar
Thompson, K., Bakker, J.P. and Bekker, R.M. (1997) The soil seed banks of north west Europe: Methodology, density and longevity. Cambridge, Cambridge University Press.Google Scholar
Thompson, K., Bakker, J.P., Bekker, R.M. and Hodgson, J.G. (1998) Ecological correlates of seed persistence in soil in the NW European flora. Journal of Ecology 86, 163169.CrossRefGoogle Scholar
Tsuyuzaki, S. (1991) Survival characteristics of buried seeds 10 years after the eruption of the Usu volcano in northern Japan. Canadian Journal of Botany 69, 22512256.CrossRefGoogle Scholar
Tutin, T.G., Heywood, V.H., Burgess, N.A., Moore, D.M., Valentine, D.H., Walters, S.M. and Webb, D.A. (Eds) (19681996). Flora Europaea. Cambridge, Cambridge University Press.Google Scholar
Vander Wall, S.B. (1993) Seed water content and the vulnerability of buried seeds to foraging rodents. American Midland Naturalist 129, 272281.CrossRefGoogle Scholar
Vander Wall, S.B. (1995) Influence of substrate water on the ability of rodents to find buried seeds. Journal of Mammalogy 76, 851856.CrossRefGoogle Scholar
Vander Wall, S.B. (1998) Foraging success of granivorous rodents: Effects of variation in seed and soil water on olfaction. Ecology 79, 233241.CrossRefGoogle Scholar
Venable, D.L. and Brown, J.S. (1988) The selective interactions of dispersal, dormancy, and seed size as adaptations for reducing risk in variable environments. The American Naturalist 131, 360384.CrossRefGoogle Scholar