title: A new method to determine the oxygen concentration inside the sapwood of trees.
abstract: Research into the short-term fluctuations of oxygen concentrations in tree stems has been hampered by the difficulty of measuring oxygen inside tissues. A new method, which is based on fluorescence quenching of a ruthenium complex in the presence of oxygen, has been applied to measure changes of oxygen concentration in the sapwood of trees. During a field day-course oxygen increased with the radiation load and fell during the night (in Fagus orientalis from 20.3% in the afternoon to 17.5% in the morning next day). In a greenhouse experiment the sapwood oxygen concentration of Laurus nobilis could be influenced by flooding the root system. The very fast response, high resolution (better than 0.1%), easy calibration, and dependence only on oxygen and temperature make the technique well suited for measurements of oxygen concentrations in the sapwood.
authors.affiliation: Institut für Botanik, Universität für Bodenkultur Wien, Gregor Mendel Str. 33, A-1180 Wien, Austria. adelhier@edv1.boku.ac.at
authors.forename: Andrés Miguel
authors.initials: AM
authors.lastname: del Hierro
authors.forename: Winfried
authors.initials: W
authors.lastname: Kronberger
authors.forename: Peter
authors.initials: P
authors.lastname: Hietz
authors.forename: Ivo
authors.initials: I
authors.lastname: Offenthaler
authors.forename: Hanno
authors.initials: H
authors.lastname: Richter
mesh_terms: D000465:Algorithms; D004780:Environment, Controlled; D029964:Fagus / Q000737:chemistry / Q000528:radiation effects; D027442:Laurus / Q000737:chemistry / Q000528:radiation effects; D010100:Oxygen / Q000032:analysis* / Q000378:metabolism / Q000528:radiation effects; D018517:Plant Roots / Q000737:chemistry / Q000187:drug effects; D018547:Plant Stems / Q000737:chemistry* / Q000528:radiation effects; D018526:Plant Transpiration / Q000187:drug effects / Q000528:radiation effects; D013696:Temperature; D014197:Trees / Q000737:chemistry* / Q000528:radiation effects; D014867:Water / Q000494:pharmacology; D014934:Wood
chemical_list: D014867:Water; D010100:Oxygen