Deuterium in water vapor evaporated from a coastal salt marsh

Citation
H. He et al., Deuterium in water vapor evaporated from a coastal salt marsh, J GEO RES-A, 106(D11), 2001, pp. 12183-12191
Citations number
23
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Earth Sciences
Volume
106
Issue
D11
Year of publication
2001
Pages
12183 - 12191
Database
ISI
SICI code
Abstract
Atmospheric water vapor was sampled simultaneously at two heights in the at mospheric surface layer above a coastal salt marsh near New Haven, Connecti cut, during June 11-27, 1997, The water vapor samples were analyzed for the ir mixing ratio, Q, and deuterium isotope ratio, deltaD. The observed SD va ried in the range of -145 to -89 per mil and was positively correlated with Q, reflecting the influence of in-cloud condensation and surface evapotran spiration processes at a regional scale. Both Q and deltaD were, in general , lower at the upper level, indicating an upward transport of (H2O)-O-16 an d (HDO)-O-16. The Craig-Gordon model reproduced reasonably well the combine d effects of equilibrium and kinetic fractionations and atmospheric demand on the evaporation process. Transpiration of the marsh plants, Spartina pat ens (Ait.), was a minor component (11%) of the total evapotranspiration dur ing the experimental period. We also suggest that the relationship between deltaD and salinity, S, of the marsh surface water can be used to infer the isotope flux ratio. More data, however, are needed to verify this mass bal ance approach.