Institute of Botany
Sect. Plant Ecology
1. Treeline trees in a CO₂-enriched world - Introduction
 Dischma valley, near Davos  Bird's eye view of the Stillberg site  Liquid CO₂ supply  Study species: Larix decidua and Pinus uncinata  CO₂-enrichment of treeline conifers |
The «Stillberg» Free Air CO₂ Enrichment (FACE) experiment was established in 2001 and has been successfully in operation for four growing seasons with the support of a dedicated team and the Swiss National Foundation. It is located on a mountain called Stillberg (Davos, GR) where a long-term research site of the Swiss Federal Institute for Snow and Avalanche Research exists.
The goal is to expose natural vegetation at the upper altitudinal treeline to an elevated atmospheric CO₂ concentration expected in the near future in order to investigate whether tree growth at treeline is carbon limited, and what changes are to be expected in the treeline ecotone with the continuing rise in atmospheric CO₂ concentration.
Major research activities are related to growth and carbon allocation in the two tree species Larix decidua and Pinus uncinata, growth of dwarf shrub species, potential advantages for hemi-parasitic plants such as Melampyrum, performance of herbivores feeding on CO₂-exposed forage plants, and to carbon and nutrient flux questions at the ecosystem level. These latter topics include a spectrum of soil related questions such as the effect of elevated CO₂ on dissolved organic carbon, soil respiration, and ectomycorrhizal development in treeline conifers.
Selected topics:
1. Introduction [this page]
2. Technology of CO₂ enrichment
3. Tree growth
4. Dwarf shrub growth
5. Carbon allocation in branch wood
6. Plant-insect interactions
7. Treeline conifer ectomycorrhizae
8. Below-ground soil responses
9. Hemiparasite abundance
2. Technology of CO₂ enrichment
3. Tree growth
4. Dwarf shrub growth
5. Carbon allocation in branch wood
6. Plant-insect interactions
7. Treeline conifer ectomycorrhizae
8. Below-ground soil responses
9. Hemiparasite abundance
Publications
| Asshoff R, Hättenschwiler S 2006: Changes in needle quality and larch bud moth performance in response to CO₂-enrichment and defoliation of treeline larches. Ecol Entomol 31:84-90 | ||
| Asshoff R, Hättenschwiler S 2005: Growth and reproduction of the alpine grasshopper Miramella alpina feeding on CO₂-enriched dwarf shrubs at treeline. Oecologia 142:191-201 | abstract | |
| Handa IT, Körner C, Hättenschwiler S 2005: A test of the treeline carbon limitation hypothesis by in situ CO₂ enrichment and defoliation. Ecology 86:1288-1300 | abstract | |
| Handa IT, Körner C, Hättenschwiler S 2005: Stem responses of treeline conifers to four years of in situ CO₂ enrichment. In preparation. | ||
| Hättenschwiler S, Zumbrunn T 2006: Global change driven increased hemiparasite abundance in an alpine treeline ecotone. Oecologia 147:47-52 | ||
| Hättenschwiler S, Handa IT, Egli L, Asshoff R, Ammann W, Körner Ch 2002: Atmospheric CO₂ enrichment of alpine treeline conifers. New Phytol 156:363-375 | abstract | |
| Serio D 2004: Mycorrhizal infection of seedlings at the Swiss treeline: effects of CO₂ enrichment, defoliation and host species. Diploma thesis, Institute of Botany, University of Basel. | ||
| von Felten S, Hättenschwiler S, Saurer M, Siegwolf R 2005: Carbon allocation in shoots of alpine treeline conifers in a CO₂ enriched environment. Submitted. | ||
| von Felten, S 2003: Carbon allocation in new shoots of alpine treeline conifers in a CO₂ enriched environment. Diploma thesis, Institute of Botany, University of Basel. | ||
| Zumbrunn T 2004: Alpine dwarf shrubs in a CO₂ enriched world. Diploma thesis, Institute of Botany, University of Basel. | ||
| Zumbrunn T, Hättenschwiler S 2005: Species specific growth responses of alpine dwarf shrubs after four years of CO₂ enrichment. In preparation. |
Inquiries
Graduate Students
Roman Asshoff, Tanya Handa, Daniela Serio, Stefanie von Felten, Thomas Zumbrunn
Technical team
Erwin Amstutz, Georges Grun, Luca Egli, Alain Studer
External partners
•Dr. Walter Ammann, Eidg. Forschungsanstalt WSL/SLF, Flüalastrasse 11, 7260 Davos, Switzerland
•Dr. Peter Bebi, Eidg. Forschungsanstalt WSL/SLF, Flüelastrasse 11, 7260 Davos, Switzerland
•Dr. Rolf Siegwolf, Paul Scherrer Institut (PSI), Laboratory of Atmospheric Chemistry, 5232 Villigen PSI, Switzerland
•Dr. Simon Egli, Eidg. Forschungsanstalt für Wald, Schnee und Landschaft (WSL), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
•Dr. Frank Hagedorn, Eidg. Forschungsanstalt für Wald, Schnee und Landschaft (WSL), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
•Dr. Peter Bebi, Eidg. Forschungsanstalt WSL/SLF, Flüelastrasse 11, 7260 Davos, Switzerland
•Dr. Rolf Siegwolf, Paul Scherrer Institut (PSI), Laboratory of Atmospheric Chemistry, 5232 Villigen PSI, Switzerland
•Dr. Simon Egli, Eidg. Forschungsanstalt für Wald, Schnee und Landschaft (WSL), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
•Dr. Frank Hagedorn, Eidg. Forschungsanstalt für Wald, Schnee und Landschaft (WSL), Zürcherstrasse 111, 8903 Birmensdorf, Switzerland
Links
•Swiss Federal Institute for Snow and Avalanche Research
•Laboratory of Atmospheric Chemistry (Paul Scherrer Institut)
•Swiss Federal Institute for Forest, Snow and Landscape Research
•Laboratory of Atmospheric Chemistry (Paul Scherrer Institut)
•Swiss Federal Institute for Forest, Snow and Landscape Research
Photographs
Thomas Zumbrunn (if not stated otherwise)