| Autor: |
Gerrit W. Heil, J. J. Mols, Jan Duyzer, J.W. Erisman, G.P. Wyers, M. Raessen, Roland Bobbink, J. E. M. Hogenkamp, B.G. van Elzakker, H. Verhage, E. Zwart, F.G. Römer, René Otjes, L. Van Den Beld, M.G. Mennen |
| Rok vydání: |
1994 |
| Předmět: |
|
| Zdroj: |
Atmospheric Environment. 28:487-496 |
| ISSN: |
1352-2310 |
| DOI: |
10.1016/1352-2310(94)90126-0 |
| Popis: |
A three-year experiment for the determination of deposition fluxes on heathland was conducted at the Elspeetsche Veld involving several research groups. Micro-meteorological measurements of SO 2 , NH 3 and NO 2 were made using different techniques. Furthermore, throughfall and bulk precipitation fluxes of SO 4 2− , NH 4 + and NO 3 − were also measured. From these measurements, deposition parameters were derived to yield a generalized description of the surface exchange of these trace gases, including possible interactions. For SO 2 , generally low surface resistances were found; the annual average dry deposition velocity ranged from 0.8 to 1.0 cm s −1 . The annual flux of SO 2 was estimated as 250 mol ha −1 yr −1 . For NH 3 also, low R c values were observed, yielding annual average V d of 0.8 cm s −1 . The annual flux of NH 3 was estimated as 850 mol ha −1 yr −1 . Under the environmental conditions prevailing in the Netherlands, co-deposition between SO 2 and NH 3 was estimated to be irrelevant. Surface wetness was found to be the dominating factor influencing dry deposition of the two gases. R c values for NO 2 stomatal behaviour, V d for this gas ranged from 0.1 to 0.4 cm s −1 . Fluxes measured with the throughfall method are compared with fluxes derived using micro-meteorological methods. The yearly average net throughfall flux for SO 4 and the dry deposition flux (SO 2 and SO 4 particles) amounted 500 and 350 mol ha −1 yr −1 , respectively. For NH 4 this was 1180 and 930 mol ha −1 yr −1 , respectively. The correlation between the two on a monthly basis is significant ( r =0.50 for SO 4 and r =0.52 for NH 4 , n = 12, p |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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