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What are the relative roles of biological production, micrometeorology, and photochemistry in controlling the flux of trace gases between terrestrial ecosystems and the atmosphere?

Welche Rolle spielen biologische Produktion, Mikrometeorologie und Photochemie in der Kontrolle von Spurengasflüssen zwischen terrestrischen Ökosystemen und der Atmosphäre
: Vitousek, P.M.; Denmead, O.T.; Fowler, D.; Johansson, C.; Kesselmeier, J.; Klemendtsson, L.; Meixner, F.X.; Mosier, A.R.; Schütz, H.; Stal, L.J.; Wahlen, M.

Exchange of trace gases between terrestrial ecosystems and the atmosphere
Chicester: Wiley and Sons, 1989
Dahlem Konferenzen <1989>
Fraunhofer IFU; 2002 in Helmholtz-Gesellschaft integriert
Austausch; Biosphäre-Atmosphäre Austausch; biosphere-atmosphere exchange; ecosystem; exchange; Meßtechnik; micrometeorology techniques; Mikrometeorologie; Ökosystem; Photochemie; photochemistry; Spurengas; trace gases

Discussions within the group focused on the relative roles of biological production and consumption, micrometeorology, and photochemistry in the transfer of trace gases between vegetated surfaces and the atmosphere. Both the composition of the group and its charge precluded a serious discussion of photochemical sinks for trace gases in the stratosphere or troposphere. Within the range of interactions considered, we concluded that biological processes are overwhelmingly dominant in the control of N2O, Ch4, and NOx fluxes. For reactive gases (i.e. NO itself), micrometeorological and chemical processes can modify the extent to which biological processes control net exchanges between terrestrial surfaces and the atmosphere. Additionally, we concluded that the lack of micrometeorological methods for measuring integrated fluxes of N2O and CH4, limits our ability to unterstand their dynamics, and a dearth of information on the biological mechanisms involved in NOx uptake limits our understand ing of NOx exchange. In this report, we summarize the information and assumptions that underlie these conclusions. We describe constraints or methods for measuring trace gas fluxes, the importance of plants in modifying fluxes from soil, and the dynamics of NOx within and above vegetation canopies as they are influenced by physiological mechanisms, photochemistry, and patterns of air movement. We conclude with a brief discussion of possible changes in the relative roles on these processes on a changing Earth and a discussion of what now limits our ability "to analyze the biological and physicochemical regulation of trace gas exchange for modeling on local to global scales, and to evaluate the importance of trace gas exchange to ecology, climate, and atmospheric chemistry."