1. Longevity of seeds in a glacier foreland of the Central Alps - a burial experiment Erich Schwienbacher & Brigitta Erschbamer Institute of Botany University of Innsbruck Contact: erich.schwienbacher@uibk.ac.at 15th annual meeting of the Section Plant Population Biologie of the Society for Ecology, May 2002

2. Introduction  Seed germination: important life history trait  Seed banks: important sources for the regeneration

3.  Lack of knowledge about longevity of alpine seeds Introduction Controversial opinions about the glacier foreland  burial experiment

4. persistence of seeds is dependent on size (1) small seeds  long-lived (2) big seeds  short-lived Hypotheses but independently of the size (3) hard-coated seeds  long-lived

5. ROTMOOSFERNER Tyrol, Austria burial site 2300 - 2400 m a.s.l. 46°49‘N 11°02‘E glacier foreland

6. Saxifraga aizoides Saxifraga oppositifolia Linaria alpina Achillea moschata Artemisia genipi Trifolium pallescens Oxyria digyna Geum reptans Anthyllis alpestris Species used for the experiment

7. Types of seeds small Saxifraga aizoides big Anthyllis alpestris Trifolium pallescens hard-coated

8. Design of experiment 1-year 2-year 5-year 4 groups 9 species 100 seeds 5 replicates fresh field experiment

9. Protocol of the burial experiment and the germination test stratification (+ 4°C) growth chamber: germination test - 10 days germination rate ‚scarified seeds‘ scarification of hard-coated seeds germination rate ‚growth chamber‘ growth chamber: germination test - 100 days fresh seeds

10. field experiment 1-year burial Protocol of the burial experiment and the germination test fresh seeds growth chamber: germination test - 10 days scarification of hard-coated seeds germination rate ‚scarified seeds‘ germination rate ‚growth chamber‘ growth chamber: germination test - 100 days stratification (+ 4°C) stratification + germination in the field germination rate ‚field‘

11. Protocol of the burial experiment and the germination test field experiment 1-year burialfresh seeds growth chamber: germination test - 10 days scarification of hard-coated seeds germination rate ‚scarified seeds‘ germination rate ‚growth chamber‘ growth chamber: germination test - 100 days stratification + germination in the field stratification (+ 4°C) germination rate ‚field‘ 2-year burial5-year burial

12. Results fresh seeds

13. Results fresh seeds: 1-year burial: but:increasing germination rates with increasing seed weight  high germination rates (42.7 % ± 34.7)  mostly low germination rates (10.6 % ± 13.8)

14. Results log seed weight log no. of seedlings R²=0.82 Regression: seed weight/number of seedlings 1-year burial

15. Results fresh seeds 1-year burial hard-coated seeds: Linaria alpina, Trifolium pallescens, Anthyllis alpestris

16. Conclusions (1) hard-coated seeds (2) big seeds (3) small seeds  loose their viability during the first winter ?  secondary dormancy takes place ? or  potential to form persistent seed banks  germinate after the first year in the field

17. Future For how long do seeds persist in the glacier foreland?  2-year burial 5-year burial

18. Acknowledgements Jürg Stöcklin Colleagues of the Univ. Innsbruck Austrian Academy of Science Thank you for your attention! Contact: erich.schwienbacher@uibk.ac.at