Lars Eklundh
Professor
Upscaling Northern Peatland CO2 Fluxes Using Satellite Remote Sensing Data
Författare
Summary, in Swedish
Peatlands play an important role in the global carbon cycle as they contain a large soil carbon stock. However, current climate change could potentially shift peatlands from being carbon sinks to carbon sources. Remote sensing methods provide an opportunity to monitor carbon dioxide (CO2) exchange in peatland ecosystems at large scales under these changing conditions. In this study, we developed empirical models of the CO2 balance (net ecosystem exchange, NEE), gross primary production (GPP), and ecosystem respiration (ER) that could be used for upscaling CO2 fluxes with remotely sensed data. Two to three years of eddy covariance (EC) data from five peatlands in Sweden and Finland were compared to modelled NEE, GPP and ER based on vegetation indices from 10 m resolution Sentinel-2 MSI and land surface temperature from 1 km resolution MODIS data. To ensure a precise match between the EC data and the Sentinel-2 observations, a footprint model was applied to derive footprint-weighted daily means of the vegetation indices. Average model parameters for all sites were acquired with a leave-one-out-cross-validation procedure. Both the GPP and the ER models gave high agreement with the EC-derived fluxes (R2 = 0.70 and 0.56, NRMSE = 14% and 15%, respectively). The performance of the NEE model was weaker (average R2 = 0.36 and NRMSE = 13%). Our findings demonstrate that using optical and thermal satellite sensor data is a feasible method for upscaling the GPP and ER of northern boreal peatlands, although further studies are needed to investigate the sources of the unexplained spatial and temporal variation of the CO2 fluxes.
Avdelning/ar
- Institutionen för naturgeografi och ekosystemvetenskap
- BECC: Biodiversity and Ecosystem services in a Changing Climate
- Centrum för miljö- och klimatvetenskap (CEC)
- MERGE: ModElling the Regional and Global Earth system
- ICOS Sweden
Publiceringsår
2021-02-23
Språk
Engelska
Publikation/Tidskrift/Serie
Remote Sensing
Volym
13
Issue
4
Dokumenttyp
Artikel i tidskrift
Förlag
MDPI AG
Ämne
- Physical Geography
Nyckelord
- Ecosystem respiration (ER)
- Footprint analysis
- Gross primary production (GPP)
- Net ecosystem exchange (NEE)
- Peatland
- Sentinel-2
- Upscaling
Aktiv
Published
Projekt
- CarboScale : Scaling carbon flux from towers to the northern landscape
- Upscaling carbon fluxes to a landscape
ISBN/ISSN/Övrigt
- ISSN: 2072-4292