A new mass conservation approach to the study of CO2 advection in an alpine forest
JournalArticle (Originalarbeit in einer wissenschaftlichen Zeitschrift)
ID 157820
Author(s) Montagnani, L.; Manca, G.; Canepa, E.; Georgieva, E.; Acosta, M.; Feigenwinter, C.; Janous, D.; Kerschbaumer, G.; Lindroth, A.; Minach, L.; Minerbi, S.; Mölder, M.; Pavelka, M.; Seufert, G.; Zeri, M.; Ziegler, W.
Author(s) at UniBasel Feigenwinter, Christian
Year 2009
Title A new mass conservation approach to the study of CO2 advection in an alpine forest
Journal Journal of geophysical research. D, Atmospheres
Volume 114
Pages / Article-Number 25
Abstract A new method is proposed for the computation of CO 2 Net Ecosystem Exchange(NEE) and its components in a forest ecosystem. Advective flux is estimated by takinginto account the air mass conservation principle. For this purpose, wind and dry airdensity values on the surface of the control volume are first corrected and then theadvective flux is estimated on the surface of the control volume. Turbulent flux is alsocomputed along the surface of the control volume while storage flux is computed insidethe volume. Additional characteristics of this method are that incompressibility of themean flow is not assumed a priori, and that vertical and horizontal advective fluxes are nottreated separately, but their sum is estimated directly. The methodology is applied toexperimental data collected with a three-dimensional scheme at the alpine site of Renonduring the Advex project (July 2005). The advection flux was found to be prevailingpositive at night and negative during the day, as was found in previous studies onadvection for the same site, but showed a lower scatter in half-hour calculated values. Wetested the effect of its summation on turbulent and storage fluxes to produce half-hourlyvalues of NEE. Nighttime NEE values were used in functional relations with soiltemperature, daytime values with PPFD. The effect of addition of the advectioncomponent was an increase in the values of parameters indicating ecosystem respiration,quantum yield, and photosynthetic capacity. The coefficient of correlation between NEEand environmental drivers increased.
Publisher American Geophysical Union
ISSN/ISBN 0148-0227
edoc-URL http://edoc.unibas.ch/dok/A5259961
Full Text on edoc Available
Digital Object Identifier DOI 10.1029/2008JD010650
ISI-Number WOS:000265102100002
Document type (ISI) Article

MCSS v5.8 PRO. 0.442 sec, queries - 0.000 sec ©Universität Basel  |  Impressum   |