The carbon balance of a managed boreal landscape measured from a tall tower in northern Sweden

Boreal forests exchange large amounts of carbon dioxide (CO2) with the atmosphere. A managed boreal landscape usually comprises various potential CO2 sinks and sources across forest stands of varying age classes, clear-cut areas, mires, and lakes. Due to this heterogeneity and complexity, large unce...

Full description

Bibliographic Details
Published in:Agricultural and Forest Meteorology
Main Authors: Chi, Jinshu, Nilsson, Mats B., Kljun, Natascha, Wallerman, Jörgen, Fransson, Johan, Laudon, Hjalmar, Lundmark, Tomas, Peichl, Matthias
Format: Article in Journal/Newspaper
Language:English
Published: Elsevier 2019
Subjects:
Physical Geography
Forest Science
Boreal landscape
Tall tower eddy covariance
Footprint analysis
Land cover heterogeneity
CO2 Flux
Northern Sweden
Online Access:https://lup.lub.lu.se/record/10cb77c0-683b-4cb3-aae8-bacacda29f7c
https://doi.org/10.1016/j.agrformet.2019.04.010
Description
Summary:Boreal forests exchange large amounts of carbon dioxide (CO2) with the atmosphere. A managed boreal landscape usually comprises various potential CO2 sinks and sources across forest stands of varying age classes, clear-cut areas, mires, and lakes. Due to this heterogeneity and complexity, large uncertainties exist regarding the net CO2 balance at the landscape scale. In this study, we present the first estimate of the net CO2 exchange over a managed boreal landscape (∼68 km2) in northern Sweden, based on tall tower eddy covariance measurements. Our results suggest that from March 1, 2016 to February 28, 2018, the heterogeneous landscape was a net CO2 sink with a 2-year mean uptake of −87 ± 6 g C m−2 yr−1. Due to an earlier and warmer spring and sunnier autumn, the landscape was a stronger CO2 sink during the first year (−122 ± 8 g C m−2) compared to the second year (−52 ± 9 g C m−2). Footprint analysis shows that 87% of the CO2 flux measurements originated from forests, whereas mires, clear-cuts, lakes, and grassland contributed 11%, 1%, 0.7%, and 0.2%, respectively. Altogether, the CO2 sink strength of the heterogeneous landscape was up to 38% lower compared to the sink strength of a mature stand surrounding the tower. Overall, this study suggests that the managed boreal landscape acted as a CO2 sink and advocates tall tower eddy covariance measurements to improve regional carbon budget estimates.

Similar Items