Projects

Intra-annual and seasonal variability of the anatomical structure and δ13С in tree rings of coniferous and deciduous species

Scientist(s): Marina Skomarkova (Post-doc), Christian Wirth

Funding: INTAS, Max-Planck-Society

Duration: 2007-2008

Project description: Tree ring growth and wood density have been used extensively as indicators of climate change where growth is generally related to rainfall in the growing season and wood density is a predictor for summer temperatures. While these relations have been established for conifers, deciduous species have not been studied as detailed, especially with respect to wood density because of the more complicated structure and variability in their annual tree-ring growth. Tree ring carbon isotope composition could potentially help to expand the dendroclimatic analysis of deciduous and coniferous trees because δ13С in wood and cellulose are expected to also reflect climatic conditions.

The research will address the following questions: i) what is the role of climatic factors in controling the interannual variability of tree-ring width and maximum wood density in sites without strong water stress, (ii) what are the differences in tree-ring δ13С seasonal dynamics observed in conifer and deciduous trees in different years; (iii) what is the relationship between intra-annual anatomical structure and isotopic composition; (iv) is there any evidence to show that stored photosynthates significantly influence the current-year tree-ring formation and (v) what dendroclimatic application of intra-annual δ13С profiles could be extracted from the studied tree rings under these specific conditions.

The combination of routine methods of dendrochronology and stable isotope dendroeclogy is a principally new approach, which permits to indicate features of tree-ring formation in coniferous and deciduous species under different weather conditions and their response on climate change.

Collaborators: Petra Linke, Willi Brand, Alexander Kirdyanov (Krasnoyarsk), Dirk Fritzlar (Forstamt Werratal, Thueringen), Anja Fankhänel (MPI-BGC)

Publications:

Skomarkova MV, Vaganov EA, Mund M, Knohl A, Linke P, Boerner A, Schulze ED (2006) Inter-annual and seasonal variability of radial growth, wood density and carbon isotope ratios in tree rings of beech (Fagus sylvatica) growing in Germany and Italy. Trees-Structure & Function 20, 571-586

Schulze B, Wirth C, Linke P, Brand WA, Kuhlmann I, Horna V, Schulze ED (2004) Laser ablation-combustion-GC-IRMS - a new method for online analysis of intra-annual variation of delta C-13 in tree rings. Tree Physiology 24, 1193-1201