NF Scopes

Duration: 2005-2007

Contact: Matthias Saurer,

The main goal of the project is to study the influence of a changing climate on trees by analyzing the main factors controlling tree-ring growth in extreme conditions. The focus is on forest ecosystems in regions which are very sensitive to climatic changes and where rapid and dramatic environmental and climatic changes can take place, namely, the high latitude permafrost region in Central Siberia (Tura, Russia), the semi-arid dry areas in Central Asia (Bakhmal and Amankutan, Uzbekistan) and the high altitude temperature-sensitive region of the Swiss Alps (Lötschental, Switzerland). The conifer trees growing in these regions could be seriously damaged due to expected future changes in temperature, CO2 and water availability. The thawing of permafrost and increasing drought situation could be key factors influencing forest growth.

Task 1

1. Tree-ring material sampling
2. Chronology development
   • Tree-ring width
   • Tree-ring density
   • Tree-ring cell structure
   • Isotope content in wood

Task 2

1. Seasonal growth
   • Sample collection
   • Measurements
2. Water exchange
   • Sample collection
   • Measurements
   • Water isotope analysis

Task 3

1. Dendroclimatology
2. Seasonal growth modeling

Journal Articles

• Knorre, A.A., R.T.W. Siegwolf, M. Saurer, O.V. Sidorova, E.A. Vaganov, and A.V. Kirdyanov (2010), Twentieth century trends in tree ring stable isotopes (d13C and d18O) of Larix sibirica under dry conditions in the forest steppe in Siberia, Journal of Geophysical Research-Biogeosciences, 115.

• Sidorova, O.V., R.T.W. Siegwolf, M. Saurer, M.M. Naurzbaev, A.V. Shashkin, and E.A. Vaganov (2010), Spatial patterns of climatic changes in the Eurasian north reflected in Siberian larch tree-ring parameters and stable isotopes, Global Change Biology, 16 (3), 1003-1018