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11:15 am - 20/11/2012

Seminario “Surface-Atmosphere Exchange of Reactive Nitrogen Compounds” de la Dra. Ivonne Trebs

El Departamento de Ciencias Ambientales de la Facultad de Ciencias Naturales les invita al seminario “Surface-Atmosphere Exchange of Reactive Nitrogen Compounds” que ofrecerá la Dra. Ivonne Trebs del Departamento de Biogeoquímica del Max Planck Institute for Chemistry.

La actividad se llevará a cabo hoy martes 20 de noviembre de 12 m.d a 1:00 p.m. en el Anfiteatro NCN-142.

A continuación, el abstract de su investigación:

We will present our recent results on the surface atmosphere-exchange fluxes of reactive nitrogen compounds (Nr). These include nitrogen monoxide (NO), nitrogen dioxide (NO2), nitrous acid (HONO) and peroxyacetyl nitrate (PAN).  Exchange fluxes of Nr are influenced by turbulence-chemistry interactions at the soil-vegetation-atmosphere interfaces. In and above tall canopies (forest) the magnitude and direction of Nr fluxes are controlled by physicochemical and/or surface characteristics as well as by the interaction of turbulent transport and chemical reactions of trace compounds. We have investigated these processes at a natural (nutrient-poor) grassland ecosystem using eddy covariance, relaxed eddy accumulation, aerodynamic gradient and chamber methods. The residence time of the air within the grass canopy was investigated using the Radon tracer technique. We also found that HONO is released from soil as a function of temperature and soil water content, comparable to typically observed soil biogenic NO emissions. For natural ecosystems this implies that deposited Nr is re-cycled to the atmosphere.