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41	Adaptation and acclimation of red alder (Alnus rubra) in two common gardens of contrasting climate Porter, Brendan 22 December 2011 (has links) Red alder (Alnus rubra Bong.) is the only tree in British Columbia and the Northwest US to engage in actinorhizal symbiosis to fix atmospheric nitrogen. This study was conducted to explore the plasticity in growth and physiology among 58 17-year-old red alder families in response to variation in climate in two common garden plots, one at Bowser, BC and one at Terrace, BC. Physiological assessments included height and diameter growth, bud flush, water use efficiency as measured by δ13C, cold hardiness as measured by controlled freezing and electrolyte leakage, autumn leaf senescence, and instantaneous and seasonally integrated rates of nitrogen fixation as measured by acetylene reduction and natural abundance δ15N isotope analysis, respectively. Significant differences were identified among families for growth (height and diameter), bud burst stage, leaf senescence, cold hardiness, and bud nitrogen content. No significant differences among families were identified for water use efficiency as measured by δ13C, or for rates of nitrogen fixation as measured by either acetylene reduction or natural abundance δ15N. This study identified possible adaptive differences among red alder genotypes, especially in traits such as bud flush timing, cold hardiness, or nitrogen fixation and their respective contributions to growth. These differences often reflected a tradeoff between growth and the ability to tolerate an extreme environment. Cold hardiness results indicate that red alder families are well adapted to their climate of origin, and may not be able to acclimate sufficiently to a northward assisted migration of genotypes. Nitrogen fixation results demonstrated gaps in our current knowledge of Frankia distribution and impact on the actinorhizal symbiosis in British Columbia. / Graduate actinorhizal Frankia nitrogen fixation cold hardiness water use efficiency phenology leaf senescence bud burst frost hardiness cold tolerance root nodules tree physiology plant physiology common garden silviculture genotype x environment δ13C δ15N Acetylene Reduction Assay Acetylene reduction electrolyte leakage stable N isotope stable C isotope
42	Stable isotope investigations on speleothems from different cave systems in Germany. / Stabile Isotopen-Untersuchungen an Speläothemen aus verschiedenen Höhlensystemen in Deutschland. Nordhoff, Peter 13 June 2005 (has links) No description available. 550 Geowissenschaften VAO 200 VDI 200 VDI 210 VDI 220 VEB 127 VEB 147 VJJ 100 Mathematics and Natural Science Speläotheme Stalagmiten Stalaktiten Tropfwasser Deutschland Schwäbische Alb Fränkische Alb Harz Paläoklima δ18O/δ13C stabile Isotope 234U/230Th TIMS Zaininger Höhle Hintere Kohlhaldenhöhle Baumannshöhle Herrmannshöhle Mühlbachquellhöhle Höhlenruine Hunas thermodynamische Equilibrium kinetische Fraktionierung OIS2 Jüngere Dryas Bölling/Alleröd T1 Pleistozän Holozän 8.2ka Holozänes Optimum speleothem stalagmites stalactites dripwater Germany Swabian Alb Franconian Alb Harz Mountains paleoclimate δ18O/δ13C stable isotopes 234U/230Th TIMS Zaininger Cave Hintere Kohlhalden Cave Baumanns-Cave Herrmanns-Cave Mühlbach-Cave Paleocave Hunas hendy test equilibrium conditions kinetic fractionation OIS2 Younger Dryas Bölling/Alleröd T1 Pleistocene Holocene 8.2 kyr. Holocene Climatic Optimum 38.03 38.82 38.17 38.19 38.32

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Adaptation and acclimation of red alder (Alnus rubra) in two common gardens of contrasting climate

Stable isotope investigations on speleothems from different cave systems in Germany. / Stabile Isotopen-Untersuchungen an Speläothemen aus verschiedenen Höhlensystemen in Deutschland.