INIBIOMA   20415
INSTITUTO DE INVESTIGACIONES EN BIODIVERSIDAD Y MEDIOAMBIENTE
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
First seasonal atmospheric total gaseous mercury (TGM) records in Southern South America: INIBIOMA GMOS Station, Nahuel Huapi National Park.
Autor/es:
DIEGUEZ, M. C.; PATRICIA E., GARCIA
Lugar:
Roma
Reunión:
Workshop; Workshop; GMOS QA/QC Worshop; 2013
Institución organizadora:
CONSIGLIO NAZIONALE DELLA RICHERZA ITALIA
Resumen:
In this presentation we report the first seasonal records of Total
gaseous mercury (TGM) in a new mercury monitoring station of the project Global
Mercury Observation System of the 7th Frame Program of the European Union
located in nahuel Huapi National Park (Lab Fotobiología, INIBIOMA-CONICET). TGM
is the sum of gaseous elemental mercury (Hg0; GEM) and gaseous oxidised mercury
(GOM), which may constitute from both inorganic and organic gaseous mercury
species. Hg0 is generally the most dominating mercury species in the background
atmosphere and constitutes often more than 98% of the total gaseous mercury.
Automatic TGM instruments use the amalgamation technique to trap gaseous mercury
in the air. Exactly determined air volumes are pulled through a cartridge
containing an adsorbent (a gold surface), onto which all gaseous mercury
quantitatively is adsorbed. The mercury is then thermally desorbed as GEM (Hg0)
and detected by a Tekran 2537 B unit which is a Cold Vapour Atomic Fluorescence
Spectrometer CVAFS. The TGM concentration is presented as ng of Hg0 per m3,
using volumes at standard pressure and temperature. Daily record of TGM in
Bariloche fluctuated between 0.6 and 1.7 ng m-3 in a daily basis. The daily
pattern found clearly shows lower TGM values during night-time and higher
values during daytime, which may reflect photo-oxidation in the lower
atmosphere and Hg0 liberation by photo-oxidation from freshwater masses
surrounding the station.