Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space

S Launiainen, J Rinne, J Pumpanen, L Kulmala, P Kolari, P Keronen, E Siivola, T Pohja, P Hari, T Vesala

Tutkimustuotos: ArtikkelijulkaisuArtikkeliTieteellinenvertaisarvioitu

Kuvaus

The eddy covariance method was used to determine turbulent heat fluxes and CO2 flux below a boreal Scots pine canopy 3 m above the forest floor. Data were filtered using standard deviation of the vertical velocity as a measure of the turbulent mixing in the trunk space along with the non-stationary criterion. The turbulent transfer in the trunk space was dominated by large (15-100 m) intermittent eddies, which were detectable by the eddy covariance technique. Heat fluxes exhibited clear annual and diurnal course and amounted to 20%-30% of the fluxes above the canopy. The forest floor was a source of carbon all-year-round and the CO2 efflux was mainly controlled by soil temperature. Photosynthesis of the forest floor vegetation decreased daytime fluxes of CO2 by 1.0-1.5 mu mol m(-2) s(-1) compared with nocturnal values (similar to 3.0 mu mol m(-2) s(-1)). The eddy covariance method provided a similar daily cycle to the chamber method but there was a discrepancy between their mean levels.
Alkuperäiskielienglanti
LehtiBoreal Environment Research
Vuosikerta10
Numero6
Sivut569-588
Sivumäärä20
ISSN1239-6095
TilaJulkaistu - 2005
OKM-julkaisutyyppiA1 Alkuperäisartikkeli tieteellisessä aikakauslehdessä, vertaisarvioitu

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  • 114 Fysiikka

Lainaa tätä

@article{35b67bcaf1c44edbb5442b69b5b78b79,
title = "Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space",
abstract = "The eddy covariance method was used to determine turbulent heat fluxes and CO2 flux below a boreal Scots pine canopy 3 m above the forest floor. Data were filtered using standard deviation of the vertical velocity as a measure of the turbulent mixing in the trunk space along with the non-stationary criterion. The turbulent transfer in the trunk space was dominated by large (15-100 m) intermittent eddies, which were detectable by the eddy covariance technique. Heat fluxes exhibited clear annual and diurnal course and amounted to 20{\%}-30{\%} of the fluxes above the canopy. The forest floor was a source of carbon all-year-round and the CO2 efflux was mainly controlled by soil temperature. Photosynthesis of the forest floor vegetation decreased daytime fluxes of CO2 by 1.0-1.5 mu mol m(-2) s(-1) compared with nocturnal values (similar to 3.0 mu mol m(-2) s(-1)). The eddy covariance method provided a similar daily cycle to the chamber method but there was a discrepancy between their mean levels.",
keywords = "FREQUENCY-RESPONSE CORRECTIONS, DIOXIDE EXCHANGE-RATES, BLACK SPRUCE FOREST, CARBON-DIOXIDE, ASPEN FOREST, WATER-VAPOR, DECIDUOUS FOREST, SURFACE-LAYER, ATMOSPHERIC-TURBULENCE, CHAMBER TECHNIQUES, 114 Physical sciences",
author = "S Launiainen and J Rinne and J Pumpanen and L Kulmala and P Kolari and P Keronen and E Siivola and T Pohja and P Hari and T Vesala",
year = "2005",
language = "English",
volume = "10",
pages = "569--588",
journal = "Boreal Environment Research",
issn = "1239-6095",
publisher = "Finnish Environment Institute",
number = "6",

}

Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space. / Launiainen, S ; Rinne, J ; Pumpanen, J ; Kulmala, L ; Kolari, P ; Keronen, P ; Siivola, E ; Pohja, T ; Hari, P ; Vesala, T .

julkaisussa: Boreal Environment Research, Vuosikerta 10, Nro 6, 2005, s. 569-588.

Tutkimustuotos: ArtikkelijulkaisuArtikkeliTieteellinenvertaisarvioitu

TY - JOUR

T1 - Eddy covariance measurements of CO2 and sensible and latent heat fluxes during a full year in a boreal pine forest trunk-space

AU - Launiainen, S

AU - Rinne, J

AU - Pumpanen, J

AU - Kulmala, L

AU - Kolari, P

AU - Keronen, P

AU - Siivola, E

AU - Pohja, T

AU - Hari, P

AU - Vesala, T

PY - 2005

Y1 - 2005

N2 - The eddy covariance method was used to determine turbulent heat fluxes and CO2 flux below a boreal Scots pine canopy 3 m above the forest floor. Data were filtered using standard deviation of the vertical velocity as a measure of the turbulent mixing in the trunk space along with the non-stationary criterion. The turbulent transfer in the trunk space was dominated by large (15-100 m) intermittent eddies, which were detectable by the eddy covariance technique. Heat fluxes exhibited clear annual and diurnal course and amounted to 20%-30% of the fluxes above the canopy. The forest floor was a source of carbon all-year-round and the CO2 efflux was mainly controlled by soil temperature. Photosynthesis of the forest floor vegetation decreased daytime fluxes of CO2 by 1.0-1.5 mu mol m(-2) s(-1) compared with nocturnal values (similar to 3.0 mu mol m(-2) s(-1)). The eddy covariance method provided a similar daily cycle to the chamber method but there was a discrepancy between their mean levels.

AB - The eddy covariance method was used to determine turbulent heat fluxes and CO2 flux below a boreal Scots pine canopy 3 m above the forest floor. Data were filtered using standard deviation of the vertical velocity as a measure of the turbulent mixing in the trunk space along with the non-stationary criterion. The turbulent transfer in the trunk space was dominated by large (15-100 m) intermittent eddies, which were detectable by the eddy covariance technique. Heat fluxes exhibited clear annual and diurnal course and amounted to 20%-30% of the fluxes above the canopy. The forest floor was a source of carbon all-year-round and the CO2 efflux was mainly controlled by soil temperature. Photosynthesis of the forest floor vegetation decreased daytime fluxes of CO2 by 1.0-1.5 mu mol m(-2) s(-1) compared with nocturnal values (similar to 3.0 mu mol m(-2) s(-1)). The eddy covariance method provided a similar daily cycle to the chamber method but there was a discrepancy between their mean levels.

KW - FREQUENCY-RESPONSE CORRECTIONS

KW - DIOXIDE EXCHANGE-RATES

KW - BLACK SPRUCE FOREST

KW - CARBON-DIOXIDE

KW - ASPEN FOREST

KW - WATER-VAPOR

KW - DECIDUOUS FOREST

KW - SURFACE-LAYER

KW - ATMOSPHERIC-TURBULENCE

KW - CHAMBER TECHNIQUES

KW - 114 Physical sciences

M3 - Article

VL - 10

SP - 569

EP - 588

JO - Boreal Environment Research

JF - Boreal Environment Research

SN - 1239-6095

IS - 6

ER -