Webbläsaren som du använder stöds inte av denna webbplats. Alla versioner av Internet Explorer stöds inte längre, av oss eller Microsoft (läs mer här: * https://www.microsoft.com/en-us/microsoft-365/windows/end-of-ie-support).

Var god och använd en modern webbläsare för att ta del av denna webbplats, som t.ex. nyaste versioner av Edge, Chrome, Firefox eller Safari osv.

Default user image.

Meelis Mölder

Forskningsingenjör

Default user image.

A new mass conservation approach to the study of CO2 advection in an alpine forest

Författare

  • Leonardo Montagnani
  • Giovanni Manca
  • Elisa Canepa
  • Emilia Georgieva
  • Manuel Acosta
  • Christian Feigenwinter
  • Dalibor Janous
  • Guenther Kerschbaumer
  • Anders Lindroth
  • Luigi Minach
  • Stefano Minerbi
  • Meelis Mölder
  • Marian Pavelka
  • Guenther Seufert
  • Marcelo Zeri
  • Waldemar Ziegler
Visa allt

Summary, in English

A new method is proposed for the computation of CO2 Net Ecosystem Exchange (NEE) and its components in a forest ecosystem. Advective flux is estimated by taking into account the air mass conservation principle. For this purpose, wind and dry air density values on the surface of the control volume are first corrected and then the advective flux is estimated on the surface of the control volume. Turbulent flux is also computed along the surface of the control volume while storage flux is computed inside the volume. Additional characteristics of this method are that incompressibility of the mean flow is not assumed a priori, and that vertical and horizontal advective fluxes are not treated separately, but their sum is estimated directly. The methodology is applied to experimental data collected with a three-dimensional scheme at the alpine site of Renon during the Advex project (July 2005). The advection flux was found to be prevailing positive at night and negative during the day, as was found in previous studies on advection for the same site, but showed a lower scatter in half-hour calculated values. We tested the effect of its summation on turbulent and storage fluxes to produce half-hourly values of NEE. Nighttime NEE values were used in functional relations with soil temperature, daytime values with PPFD. The effect of addition of the advection component was an increase in the values of parameters indicating ecosystem respiration, quantum yield, and photosynthetic capacity. The coefficient of correlation between NEE and environmental drivers increased.

Avdelning/ar

  • Institutionen för naturgeografi och ekosystemvetenskap

Publiceringsår

2009

Språk

Engelska

Publikation/Tidskrift/Serie

Journal of Geophysical Research

Volym

114

Dokumenttyp

Artikel i tidskrift

Förlag

Wiley-Blackwell

Ämne

  • Cardiac and Cardiovascular Systems
  • Respiratory Medicine and Allergy

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 2156-2202