Description: Das Projekt "Isotope pathway from atmosphere to the tree ring along a humidity gradient in Switzerland" wird vom Umweltbundesamt gefördert und von Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft durchgeführt. Temperatures in Switzerland increased about 0.57 C over the last three decades and climate models predict that this increase will continue during the 21st century and beyond. Accompanied by changes in the water supply due to the expected increase in the frequency and intensity of heavy precipitation and/or drought events, these effects will strongly force changes in forest productivity, spatial distribution of tree species, and changes in the species composition within forests. Projections of the future dimensions and interactions of these effects require detailed understanding of short and long-term changes in eco-physiological responses to past and present climate variation. Stable isotopes in tree rings have become a significant tool in obtaining retrospective insight into the plant physiological response to climate and other environmental variables. The increasing number of isotope records, however, also highlights important unsolved questions and current limitations of this tree-ring parameter. Obviously, an improved understanding of the mechanisms leading to variations in the tree's internal carbon and water cycle in relation to climate, soil moisture conditions, transpiration and expansion of the root system is urgently needed. ISOPATH aims to decipher the origin and variability of the isotopic signal in the tree rings of two alpine species, frequently used in climate reconstructions, and to understand the environmental and physiological information encoded. We will develop weekly resolved records of carbon and oxygen isotopes in xylem and needle water, needle sugars, phloem sugars and stem wood/cellulose of two physiologically differing species (larch and spruce) growing under varying temperature, soil moisture and relative humidity conditions. Those data will be related to a large suite of external variables including precipitation and soil water, temperature, and vapour pressure deficit. We act (i) on a spatial scale by following the complete pathway of stable isotopes from the atmosphere into the tree ring under varying environmental conditions and (ii) on a temporal scale by studying seasonal cycles of the isotope signals in all these different components, covering four growth seasons (2008-2011). This unique dataset in terms of length, resolution and number of measured variables will be used to test and improve advanced models for isotope fractionation at the leaf level and in the tree ring, in relation to species-specific traits, temperature and soil moisture conditions. The measured and modelled isotope signatures will allow to predict plant physiological adaptation in the alpine environment to climate change of the 21st century.
Types:
SupportProgram
Origin: /Bund/UBA/UFORDAT
Tags: Fichte ? Tierhaltungsanlage ? Jahresring ? Baumstamm ? Pflanzenphysiologie ? Zucker ? Baum ? Baumwurzel ? Zellulose ? Kohlenstoff ? Sauerstoff ? Transpiration ? Wassertemperatur ? Schweiz ? Waldfläche ? Bodenwasser ? Klimavariabilität ? Laubblatt ? Regenwasser ? Photosynthese ? Temperatur ? Dürre ? Wasserreinigung ? Wirkung ? Pflanzenwurzel ? Starkregen ? Gelöster organischer Kohlenstoff ? Isotop ? Klimaanpassung ? Artenzusammensetzung ? Bewässerung ? Dampfdruck ? Daten ? Fraktionierung ? Hochrechnung ? Jahreszeit ? Klimamodell ? Schnee ? Versorgung ? Wasseraufbereitung ? Wasserkreislauf ? Wasserversorgung ? Bodenfeuchte ? Wasserknappheit ? Wasser ? Hochgebirge ? Wirkung ? Alpen ? Messung ? Feuchtigkeit ? Abdeckung ? Kenngröße ? Klima ? Klimawandel ? Wald ? Bedarf ? Niederschlag ? Produktivität ? Fahrradfahren ? Änderung ? Atmosphäre ? Standortbedingung ? Umwelt ? Forschungseinrichtung ? SONSTIG ? WICHTIG ? PRAEZIPITATION ? BAEUME ? SPEZIFISCH ? EXTERN ? BESTANDTEIL ? Bemessung ? FORTSCHRITTLICH ? STARK ? Stall ? FRAGE ? UNGELOEST ? UNTER ? UNTERSUCHUNG ? GEBRAUCHT ? GEGENWART ? DATENSATZ ? VERANTWORTUNG ? JAHRESZEITLICH ? KURZ ? VERHAELTNIS ? MECHANISMEN ? Werkzeug ? Wachstum [biologisch] ? VERTEILUNG ? VERWANDT ? Vermehrung ? PFAD ? Vorgang ? Art [Spezies] ? DAUER ?
License: cc-by-nc-nd/4.0
Language: Deutsch
Time ranges: 2010-09-01 - 2013-08-31
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