climate; oxygen isotopes; tree rings; ecophysiology; hydrological cycle
Vitali V., Martínez-Sancho E., Treydte K., Andreu-Hayles L., Dorado-Liñán I., Gutierrez E., Helle G., Leuenberger M., Loader N., Rinne-Garmston K. T., Schleser G. H., Allen S., Waterhouse J. S., Saurer M., Lehmann M. M. (2022), The unknown third – Hydrogen isotopes in tree-ring cellulose across Europe, in Science of the Total Environment
, 813, 152281.
Treydte Kerstin, Lehmann Marco M, Wyczesany Tomasz, Pfautsch Sebastian (2021), Radial and axial water movement in adult trees recorded by stable isotope tracing, in Tree Physiology
, 41(12), 2248-2261.
Vitali Valentina, Klesse Stefan, Weigt Rosemarie, Treydte Kerstin, Frank David, Saurer Matthias, Siegwolf Rolf T W (2021), High-frequency stable isotope signals in uneven-aged forests as proxy for physiological responses to climate in Central Europe, in Tree Physiology
, 41(11), 2046-2062.
Miranda José Carlos, Lehmann Marco M, Saurer Matthias, Altman Jan, Treydte Kerstin (2021), Insight into Canary Island pine physiology provided by stable isotope patterns of water and plant tissues along an altitudinal gradient, in Tree Physiology
, 41(9), 1611-1626.
Altman Jan, Saurer Matthias, Dolezal Jiri, Maredova Nela, Song Jong-Suk, Ho Chang-Hoi, Treydte Kerstin (2021), Large volcanic eruptions reduce landfalling tropical cyclone activity: Evidence from tree rings, in Science of The Total Environment
, 775, 145899-145899.
Isaac-Renton Miriam, Montwé David, Hamann Andreas, Spiecker Heinrich, Cherubini Paolo, Treydte Kerstin (2020), Publisher Correction: Northern forest tree populations are physiologically maladapted to drought, in Nature Communications
, 11(1), 1321-1321.
Timofeeva Galina, Treydte Kerstin, Bugmann Harald, Salmon Yann, Rigling Andreas, Schaub Marcus, Vollenweider Pierre, Siegwolf Rolf, Saurer Matthias (2020), How does varying water supply affect oxygen isotope variations in needles and tree rings of Scots pine?, in Tree Physiology
, 40(10), 1366-1380.
Altman Jan, Treydte Kerstin, Pejcha Vit, Cerny Tomas, Petrik Petr, Srutek Miroslav, Song Jong Suk, Trouet Valerie, Dolezal Jiri (2020), Tree growth response to recent warming of two endemic species in Northeast Asia, in Climatic Change
, 162(3), 1345-1364.
Vannoppen Astrid, Treydte Kerstin, Boeckx Pascal, Kint Vincent, Ponette Quentin, Verheyen Kris, Muys Bart (2020), Tree species diversity improves beech growth and alters its physiological response to drought, in Trees - Structure and Function
, 34(4), 1059-1073.
Janecka Karolina, Kaczka Ryszard J., Gärtner Holger, Harvey Jill E., Treydte Kerstin (2019), Compression wood has a minor effect on the climate signal in tree-ring stable isotope records of montane Norway spruce, in Tree Physiology
, 40(8), 1014-1028.
Sargeant Christopher I., Singer Michael Bliss, Vallet‐Coulomb Christine (2019), Identification of Source‐Water Oxygen Isotopes in Trees Toolkit (ISO‐Tool) for Deciphering Historical Water Use by Forest Trees, in Water Resources Research
, 55(12), 10954-10975.
Isaac-Renton Miriam, Montwé David, Hamann Andreas, Spiecker Heinrich, Cherubini Paolo, Treydte Kerstin (2018), Northern forest tree populations are physiologically maladapted to drought, in Nature Communications
, 9(1), 5254-5254.
Insight into the trees’ physiological response to environmental change is of highest relevance for predicting how tree growth and thus the terrestrial carbon and water cycle will respond to future environmental change. Stable isotope ratios in tree tissues and particularly tree rings are key tools to examine these relationships as most climatic and physiological processes result in specific isotopic fractionation effects. Oxygen isotopes in tree rings (d18Otree-ring) can provide valuable insight into the water uptake by trees and their physiological response to hydroclimatic variation. It is, however, still unclear, what determines the d18O values of a tree’s source water, how it is coupled to d18O variation of precipitation and how it is reflected in the tree ring d18Otree-ring in relation to leaf water 18O enrichment. Particularly the interplay between isotopic signals carried in the source water and those produced at the leaf level by evaporative enrichment and physiological (post-) photosynthetic processes is still not well understood and hence, the mechanistic interpretation of d18Otree-ring time-series remains problematic. This holds especially when mechanistic isotope models are employed to simulate or interpret d18Otree-ring values as part of dynamic global vegetation models (DGVMs), which integrate many hydrological and physiological processes and could improve proxy-model comparisons.The overall objective of the proposed project is to seamlessly disentangle source water and leaf water signals in d18Otree-ring records for their ultimate use as climatic and tree physiological proxy. To achieve this aim, we will mainly built upon a unique data set of highly resolved environmental, sapflow, xylogenesis and most importantly d18O data of precipitation, soil, xylem and needle water from two physiologically differing species and three ecologically differing sites within the long-term monitoring transect Lötschental/Switzerland. In addition we will produce a well-replicated set of highly resolved d18Otree-ring records by applying a worldwide unique UV-laser microscopic dissection system at the Geo Research Center Potsdam. Furthermore, at one of our study sites we will conduct an irrigation experiment by irrigating mature trees with glacier water during a dry period in summer. Combining this great set of highly resolved empirical data with the most advanced mechanistic models of isotope fractionation in the leaf, during downstream transport and metabolic processes and wood synthesis will provide an unrivalled integrated overview of the pathways and environmental dependencies of tree-ring oxygen isotope signals and, most importantly the relatie contribution of leaf water signals and source water signals to the tree ring isotopic signature. Our findings will lead to an improved understanding of the remaining portion of unexplained variance in statistically derived climate reconstructions and should help decrease the uncertainty range in those records. Moreover, results of our data-model fusion approach will allow constrain isotope-enabled modules of DGVM frameworks to provide multiple and long-term observational constraints on model dynamics and the water cycling in terrestrial ecosystems. With that we will also contribute to an improved understanding of the mechanisms governing the terrestrial water cycle processes at the atmosphere-plant continuum under environmental change, and the implications for future biogeochemical cycles. With that we are also perfectly aligned with the research questions addressed in the Swiss Forest Lab, in particular with the study of alterations of the metabolic and biogeochemical cycles in relation to increased climate variability.