The biological drought and growth indicator network

TreeNet - biological drought and growth indicators from trees

TreeNet is an (inter-) national measurement network in which individual trees represent measurement points. Site-specific physiological data from every measured tree are sent online to a central server. 

Microclimate and tree physiology data are processed by a plant model and the ouptut delivers continuous information about the impact of current climate conditions on tree water relations and the carbon balance of forest ecosystems. Biological indicators for drought stress and growth of trees are calculated and used to estimate the water deficit of ecosystems and its consequences for the carbon turnover.

TreeNet produces the basic data needed to extrapolate research results from the eddy flux supersites Seehornwald Davos and Lägeren.

TreeNet.info is the official project homepage. Check it out for more information.

TreeNet offers scientific and public informations about:

Tree water relations:

• daily tree and ecosystem water deficits from different Swiss regions.
• half-hourly amounts of tree transpiration and its respective drought-induced down regulation by stomatal closure.
• a biological drought indicator
• amount of rain that is necessary to cover the current water deficit.
  

Carbon balance:

• half-hourly estimations of gross carbon assimilation of forests.
  
• seasonal estimations of stem growth of different tree species.
• a biological indicator for the net ecosystem productivity (NEP) of different forest types.

Methods of TreeNet

• Dendrometer to continuously measuring stem radius changes (-> PrometheusWiki).
• Sap flow sensors to estimate the water transport in trees.
• Microclimate measurements in air and soil.
• Solar powered wireless monitoring solutions to log, surveille and store data on a local server (DecentNet).
• Tree physiological tree models to interpret the data.
• Eddy covariance based measurements at selected super sites to calibrate the ordinary TreeNet sites.

TreeNet sites

TreeNet super sites:

• Seehornwald Davos (WSL/LWF/ETHZ/EMPA/BAFU)
  
• Lägeren (WSL/LWF/ETHZ/EMPA/BAFU)
  

TreeNet dendrometer sites:

• Schänis/SG (LWF) -> Link to realtime data (raw)
  
• Novaggio/TI (LWF)
• Visp/VS (LWF) -> Link to realtime data (raw)
• Lausanne/VD (LWF) -> Link to realtime data (raw)
• Muri/AG (IAP) -> Link to realtime data (raw)
• Riehen-Maienbühl/BS (IAP) -> Link to realtime data (raw)
• Wangen/ZH (IAP) -> Link to realtime data (raw)
• Beatenberg/BE (LWF) -> Link to realtime data (raw)
• Vordemwald/AG (LWF) -> Link to realtime data (raw)
• Sagno/TI (IAP) -> Link to realtime data (raw)
• Jussy/GE (LWF) -> Link to realtime data (raw)
• Bachtel (LWF) -> Link to realtime data (raw)

Project partners

• Federal Office for the environment /Bundesamt für Umwelt BAFU
• Swiss Federal Research Institute WSL
• Swiss Federal Institute of Technology Zurich ETHZ
• Institute for Applied Plant Biology IAP
• DecentLab
  

WSL Contact

Roman Zweifel

Linked projects

Tree response to climate change (WSL)

Seehornwald Davos research site (WSL)

Downloads

• Zweifel R., Etzold S., Eugster W., Zielis S., Häni M., Buchmann N. 2012. Flyer 'Baumstämme als CO₂ Reservoir?'
  
• Zweifel R., Etzold S., Zielis S., Häni M., Steppe K., Sterck F. 2012. Flyer 'Der Baumwasserhaushalt - Link zum physiologischen Verständnis von Wachstum'

• Zweifel R., Dobbertin M., Eugster W., Zielis S., Häni M., Buchmann N, Braun S. 2012. 'TreeNet - Bäume als biologische Indikatoren für Wachstum und Trockenstress von Waldökosystemen'

• Zweifel R., Eugster W., Braun S., Dobbertin M., Schaub M., Etzold S., Buchmann N.  (2011). TreeNet - Bäume als biologische Indikatoren für Trockenheit und Kohlenstoff-Aufnahme von Waldökosystemen. Poster, Forschungsmarkt Davos, 20 March 2011 (PDF 176 KB).

• Etzold, S. (2010). The carbon dioxide budget and respiration components of two contrasting forest ecosystems in the Swiss Alps. Dissertation. ETH Zurich. Diss No 19061. 176 p. (link to pdf coming soon).

• Zweifel R., Eugster W., Etzold S., Dobbertin M., Buchmann N. and Häsler R. 2010. Link between continuous stem radius changes and net ecosystem productivity of a subalpine Norway spruce forest in the Swiss Alps. New Phytologist, 187: 819-830. (PDF 510KB).
  
• Zweifel R., Steppe K. and Sterck FJ. 2007. Stomatal regulation by microclimate and tree water relations: interpreting ecophysiological field data with a hydraulic plant model. Journal of Experimental Botany, 58, 2113-2131. (PDF 1437KB).