History (CH-DAV)

Source: WSL

Text in bold refers to installations in use or measurements currently running.

1876 Beginning of standard meteorological records at Davos (MeteoSwiss). The measurements are located 2 km from the Seehornwald Davos site.
1985 Selection of the Seehornwald Davos research site for the Swiss project NRP14+ and start of the setup by R. Häsler et al.
1986-1988 Start of measurements at the Seehornwald Davos research site within the frame of NRP14+ with focus on forest decline:

  • Set up of the 35 m measurement tower and the 25 m steel frame around two trees.
  • Air chemistry monitoring (e.g. O3, NO, NO2, SO2) by W. Graber, later continued by NABEL.
  • Fine particular matter deposition (Zn, Pb, Cd) by Gehrig, EMPA
  • Microclimate profile through canopy by ETH
  • Wet and throughfall deposition by Klöti et al., EAFV. Restarted by A. Thimonier and M. Schmitt, WSL in 2009. (EAFV is the former name of the WSL).
  • Tree property measurements in a 0.25 ha plot (stem diameter, tree height, etc.). Restarted by M. Dobbertin, WSL in 2007.
  • Soil property measurements by Schindler (NABO) and Häsler et al. (EAFV).
  • Litterfall by P. Lüscher.
  • Continuous gas exchange measurement of branches by R. Häsler et al. (EAFV).
  • Fog sampling and chemical analyses by H. Turner, EAFV.


Start of continuous atmospheric NO, NO2, and O3 measurements within the Swiss national air pollution monitoring network (NABEL)
1995 Installation of eddy covariance (EC) by R. Häsler and J. Böhm (WSL)
1996 Installation of CO2 and microclimate profile on the 35 m tower by R. Häsler and J. Böhm (WSL)
1997 Installation of automatic point dendrometer by R. Häsler, K. Herzog, and R. Zweifel (WSL)
1997 Installation of Granier-type sap flow needles by R. Häsler, K. Herzog, and R. Zweifel (WSL)
1997-2005 Continuous gas exchange measurements of branches in the tree crown by R. Häsler et al. (WSL). One branch was treated with elevated CO2 concentrations.
2004 Restart of growth, tree height, and stem diameter measurements by M. Dobbertin (WSL)
2005 Closed-path system of eddy covariance was replaced by an open-path system
2006 Removal of the 25 m steel frame around two trees (NFP14+)
2006 Maintenance of eddy covariance, CO2 and microclimate profiles is transfered from R. Häsler (WSL) to W. Eugster and N. Buchmann et al. (ETHZ)
2006 An area of 25 x 70 m (1750 m2) within the NE-part of the footprint of the EC site was harvested at the end of October 2006.
2006 Installation of manual and automatic circumference bands by M. Dobbertin and R. Zweifel (WSL)
2006 Partial replacement of the original type of point dendrometers (LVTD, Agricultural Electronics Corporation, USA) by a less temperature sensitive type (ZB06/ZN12-T-WP, Natkon, Switzerland).


Integration of the site into the UN/ECE-ICP Forest Long-term forest monitoring network (LWF, WSL):

  • Annual crown condition assessment (2006)
  • LAI measurements (hemispherical photos, Licor LAI 2000) by A. Thimonier and M. Schmitt, WSL (2006)
  • Bi-annual forest health monitoring (2007)
  • Vegetation assessment every 2-4 years (2008)
  • Soil parameters by S. Zimmermann (2008)
  • Additional soil water conditions sensors by P. Waldner, E. Graf Pannatier (2008 and 2009)
  • Additional litterfall sampling (Swiss ICP-Forest Level II plot equipment)


2007 Radiation measurement below canopy by T. Jonas (SLF/WSL)
2008-2009 Heavy truck traffic through the Seehornwald Davos research site due to construction work on a nearby avalanch protection for the railway line of the Rhätische Bahn.
2008 Stem and soil respiration measurements by S. Etzold et al. (ETHZ)
2009 Continuous stem CO2 measurements by S. Etzold (ETHZ) and R. Zweifel (WSL)
2010 New 10 year contracts with the land owners of the Seehornwald Davos research site
2011-2013 Construction work of the Hotel Stilli Davos start in July 2011 (at the edge of the footprint of the eddy tower)
2011 Data acquisition system renewed and modernised. Research cabin and site cleaned from leavings of old scientific projects, P. Plüss (ETHZ), T. Baur (ETHZ), W. Eugster (ETHZ), M. Häni (ETHZ), R. Zweifel (WSL). 23-25 August 2011.
2011 Installation of additional stem CO2 sensors, M. Häni (ETHZ), R. Zweifel (WSL). 25 August 2011.
2012 Research site Seehornwald Davos joins TREENET – The biological drought and growth indicator network
2013 Research site goes ICOS – Integrated Carbon Observation System.

SNF funds first Swiss ICOS budget period 2013-2017 including the sites Seehornwald Davos (vegetation research site) and Jungfraujoch (atmospheric research site)

2014 Research site gets an additional 5 m buffer zone around the core area. Opening up new possibilities for research partners to establish projects
2014 Renewed contracts with land owners of the Seehornwald Davos research site
2015 Upgrade to ICOS class I standards. Greenhouse gas measurements (CO2, H2O, CH4 and N2O) using the eddy covariance technique (measured and maintained by ETH Zurich), meteorology (by EMPA/NABEL), and measurements of tree width, stem CO2 exchange as well as leaf area index, biomass, N losses etc. (by WSL Birmensdorf/LWF/TreeNet)
2016 Half a dozen trees were felled and their biomass fractions analysed (needles, branches, stem), dead wood was quantified and all the data were combined to obtain a detailed biomass inventory of the site, which will be used to cross-validate the flux measurements (ICOS)
2016 Hemispherical photos to estimate ‒ together with leaf area samples ‒ the leaf area index (LAI) of the vegetation (ICOS).
2017 SNF funds second Swiss ICOS budget period 2017-2021
2018 60 soil profils down to a depth of 1 m dug and analysed by S. Zimmermann et al (WSL/ICOS)
2018 Development and installation of first, automated soil GHG flux measurement chambers by P. Meier et al (ETH/ICOS)
2019 Installation of a valve switching system for storage and chamber measurements of CO2, CH4 and N2O, allowing the use of two independent gas analysers and also the measurement of two different systems (chambers and EC) with one single analyser by P. Meier et al (ETH/ICOS)
2019 ICOS CLASS 1 Label for the research station Seehornwald Davos CH-DAV.
2020 Finializing the setup of ICOS requested biomass sampling design (new and enlarged vegetation measurement plots (20 SP-plots and 4 CP-plots))
2020 SNF and SERI fund ICOS Switzerland Phase 3 (2021-2025)
2020 Spectacular helicopter operation by the Davos Forestry Service (video 1, video 2)


Last Updated on 4 Sep 2023 02:04