HR: 0800h
AN: A51B-0028    [Abstracts]
TI: Observations on the Stomatal Control of NO2 Exchange.
AU: Kesselmeier, J
EM: jks@mpch-mainz.mpg.de
AF: Max Planck Institute for Chemistry, Biogeochemistry Department, Joh.-J.-Becher-Weg 27, Mainz, 55128 Germany
AU: * Chaparro-Suarez, I G
EM: gchaparro@mpch-mainz.mpg.de
AF: Max Planck Institute for Chemistry, Biogeochemistry Department, Joh.-J.-Becher-Weg 27, Mainz, 55128 Germany
AU: Meixner, F X
EM: meixner@mpch-mainz.mpg.de
AF: Max Planck Institute for Chemistry, Biogeochemistry Department, Joh.-J.-Becher-Weg 27, Mainz, 55128 Germany
AB: Nitrogen oxides play a central role in tropospheric chemistry especially in the formation of tropospheric ozone, acid rain and hydroxyl radical as well as in CH4 and CO oxidation processes. NO2 can be assimilated and emitted by the plant leaves as well. We investigated the impact of the stomatal regulation with four tree species (Betula pendula, Fagus sylvatica, Quercus ilex und Pinus sylvestris) by exposure of leaves to the hormone abscisic acid inducing stomatal closure. The results showed that the NO2 uptake was strongly dependent on stomatal aperture. The uptake correlated linearly with stomatal (leaf) conductance in case of all four tree species investigated. In contrast an NO2 emission was observed with beech in the dark when stomata were basically closed.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0322 Constituent sources and sinks
DE: 0365 Troposphere: composition and chemistry
DE: 0426 Biosphere/atmosphere interactions (0315)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005