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From what depth do seeds emerge? A soil seed bank experiment with Mediterranean grassland species

Published online by Cambridge University Press:  22 February 2007

Juan Traba*
Affiliation:
Departamento Interuniversitario de Ecología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
Francisco M. Azcárate
Affiliation:
Departamento Interuniversitario de Ecología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
Begoña Peco
Affiliation:
Departamento Interuniversitario de Ecología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, E-28049, Spain
*
*Correspondence Fax: +34 1?397?8001, Email:, [email protected]

Abstract

Seed germination and emergence are influenced by the position of seeds in the soil bank profile. Mediterranean grasslands are heavily dependent on seed banks, as these systems are mainly composed of annual species. Seed bank germination experiments in a greenhouse were conducted to analyse the role played by burial depth on seed bank dynamics in annual Mediterranean grasslands. Specifically, they addressed two objectives: (1) to assess the ability of seeds in the shallow layer of the soil bank to emerge when they are buried at different depths, and (2) to ascertain the ability of seeds from deep layers to germinate and emerge to the surface. The study also produced a depth profile of species and seeds. The results show that: (1) all species (100%) and the majority of viable seeds (98.9%) are situated in the first centimetre, with a significant fall in the number of species and seeds in the soil bank as depth increases; (2) for the majority of species (92%) and seeds (85.4%) in the shallow bank, the emergence percentage declines significantly with burial depth; and (3) seeds that are present in deep layers need to rise to the surface in order to produce seedlings. In conclusion, the function of the seed bank in Mediterranean grasslands depends on the number of species and seeds in it, but also on the seed position in the profile and vertical movements that enable them to reach the surface.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2004

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References

Akinola, M.O., Thompson, K., and Buckland, S. M. (1998) Soil seed bank of an upland calcareous grassland after 6 years of climate and management manipulations. Journal of Applied Ecology 35, 544552Google Scholar
Azcárate, F.M., Sánchez, A.M., Arqueros, L. and Peco, B. (2002) Abundance and habitat segregation in Mediterranean grassland species: the importance of seed weight. Journal of Vegetation Science 13, 159166Google Scholar
Baker, H.G. (1989) Some aspects of the natural history of seed banks. pp. 921in Leck, M.A.;, Parker, V.T.;, Simpson, R.L. (Eds) Ecology of soil seed banks. San Diego, Academic Press.Google Scholar
Bakker, J.P., Bos, A.F., Hoogveld, J. and Muller, H.J. (1991) The role of the seed bank in restoration management of semi-arid grasslands. pp. 449455Ravera, O. (Ed.) Terrestrial and aquatic ecosystems; perturbation and recovery. New York, Ellis Horwood.Google Scholar
Baskin, C.C. and Baskin, J.M. (2001) Seeds, ecology, biogeography and evolution of dormancy and germination. San Diego, Academic Press.Google Scholar
Benech-Arnold, R.L., Ghersa, C.M., Sánchez, R.A. and García-Fernández, A.E. (1988) The role of fluctuating temperatures in the germination and establishment of Sorghum halepense (L.) Pers. Regulation of germination under leaf canopies. Functional Ecology 2, 311318Google Scholar
Benvenuti, S., Macchia, M. and Miele, S. (2001) Quantitative analysis of emergence of seedlings from buried weed seeds with increasing soil depth. Weed Science 49, 528535Google Scholar
Bewley, J.D. and Black, M. (1994) Seeds: Physiology of development and germination (2nd edition). New York, Plenum Press.Google Scholar
Chambers, J.C. and MacMahon, J.A. (1994) A day in the life of a seed: movements and fates of seeds and their implications for natural and managed systems. Annual Review of Ecology and Systematics 25, 263292CrossRefGoogle Scholar
Freas, P.R. (1989) Seed banks and vegetation processes in deserts. pp. 257281Leck, M.A.;, Parker, V.T.;, Simpson, R.L.; (Eds) Ecology of soil seed banks. San Diego, Academic Press.Google Scholar
Ghersa, C.M., Benech-Arnold, R.L. and Martínez-Ghersa, M.A. (1992) The role of fluctuating temperatures in germination and establishment of Sorghum halepense. Regulation of germination at increasing depths. Functional Ecology 6, 460468CrossRefGoogle Scholar
Grundy, A.C. and Mead, A. (1998) Modelling the effects of seed depth on weed seedling emergence. Aspects of Applied Biology 51, 7582Google Scholar
Grundy, A.C., Mead, A. and Burston, S. (1999) Modelling the effect of cultivation on seed movement with application to the prediction of weed seedling emergence. Journal of Applied Ecology 36, 663678Google Scholar
Grundy, A.C., Mead, A. and Burston, S. (2003) Modelling the emergence response of weed seeds to burial depth: interactions with seed density, weight and shape. Journal of Applied Ecology 40, 757770Google Scholar
Harper, J.L. (1977) Population biology of plants. London, Academic Press.Google Scholar
Hutchings, M.J. and Booth, K.D. (1996) Studies on the feasibility of re-creating chalk grassland vegetation on ex-arable land. II. Germination and early survivorship of seedlings under different management regimes. Journal of Applied Ecology 33, 11821190Google Scholar
Levassor, C., Ortega, M. and Peco, B. (1990) Seed banks dynamics of Mediterranean pastures subjected to mechanical disturbance. Journal of Vegetation Science 1, 339344CrossRefGoogle Scholar
MacMahon, J.A., Mull, J.F. and Crist, T.O. (2000) Harvester ants (Pogonomyrmex spp.): Their community and ecosystem influences. Annual Review of Ecology and Systematics 31, 265291Google Scholar
Marañón, T. (1998) Soil seed bank and community dynamics in an annual-dominated Mediterranean salt-marsh. Journal of Vegetation Science 9, 371378Google Scholar
McGraw, J.B. and Vavreck, M.C. (1989) Buried viable seeds in artic and alpine communities. pp. 91105in Leck, M.A., Parker, V.T.;, Simpson, R.L. (Eds) Ecology of soil seed banks. San Diego, Academic Press.Google Scholar
Moore, J.M. and Wein, R.W. (1977) Viable seed populations by soil depth and potential site recolonization after disturbance. Canadian Journal of Botany 55, 24082412Google Scholar
Murdoch, A.J. and Ellis, R.H. (2000) Dormancy, viability and longevity. pp. 183214in Fenner, M. (Ed.) Seeds. The ecology of regeneration in plant communities (2nd edition). Wallingford, CABI Publishing.Google Scholar
O'Connor, T.G. and Pickett, G.A. (1992) The influence of grazing on seed production and seed banks of some African savanna grasslands. Journal of Applied Ecology 29, 247260CrossRefGoogle Scholar
Ortega, M., Levassor, C. and Peco, B. (1997) Seasonal dynamics of Mediterranean pasture seed banks along environmental gradients. Journal of Biogeography 24, 177195CrossRefGoogle Scholar
Peart, M. H. (1984) The effects of morphology, orientation and position of grass diaspores on seedling survival. Journal of Ecology 72, 437453Google Scholar
Peco, B., Traba, J., Levassor, C., Sánchez, A. and Azcárate, F.M. (2003) Seed size, shape and persistence in dry Mediterranean grass and scrublands. Seed Science Research 13, 8795Google Scholar
Pons, T.L. (2000) Seed responses to light. pp. 237260in Fenner, M. (Ed.) Seeds. The ecology of regeneration in plant communities (2nd edition). Wallingford, CABI Publishing.CrossRefGoogle Scholar
Roberts, H.A. (1981) Seed banks in soils. Advances in Applied Biology 6, 155Google Scholar
Russi, L., Cocks, P.S. and Roberts, E.H. (1992) Seed bank dynamics in a Mediterranean grassland. Journal of Applied Ecology 29, 763771CrossRefGoogle Scholar
Smith, G.L., Freckleton, R.P., Firbank, L.G. and Watkinson, A.R. (1999) The population dynamics of Anisantha sterilis in winter wheat: comparative demography and the role of management. Journal of Applied Ecology 36, 455471CrossRefGoogle Scholar
Statsoft, Inc. (1985) STATISTICA for Windows. Tulsa, Oklahoma, StatSoft Inc.Google Scholar
Thompson, K., Grime, J.P. and Mason, G. (1977) Seed germination in response to diurnal fluctuations of temperature. Nature 267, 147149Google Scholar
Thompson, K., Green, A. and Jewels, A. M. (1994) Seeds in soil and worm casts from a neutral grassland. Functional Ecology 8, 2935Google Scholar
Traba, J., Levassor, C. and Peco, B. (1998) Concentrating samples can lead to seed losses in soil bank estimations. Functional Ecology 12, 975976Google Scholar
Willems, J.H. and Huijsmans, K.G.A. (1994) Vertical seed dispersal by earthworms: a quantitative approach. Ecography 17, 124130CrossRefGoogle Scholar
Young, J.A., Evans, R.A., Raguse, C.A. and Larson, J.R. (1981) Germinable seeds and periodicity of germination in annual grasslands. Hilgardia 49, 137CrossRefGoogle Scholar