Contrasting radiation and soil heat fluxes in Arctic shrub and wet sedge tundra ...

• Main Authors: Juszak, Inge, Eugster, Werner, Heijmans, Monique M.P.D., Schaepman-Strub, Gabriela
• Format: Article in Journal/Newspaper
• Language: English
• Published: ETH Zurich 2016
• Subjects: Active layer thickness; albedo; Arctic; Betula nana; Eriophorum; permafrost; Tundra; Siberia
• Online Access: https://dx.doi.org/10.3929/ethz-b-000118479; http://hdl.handle.net/20.500.11850/118479

Vegetation changes, such as shrub encroachment and wetland expansion, have been observed in many Arctic tundra regions. These changes feed back to permafrost and climate. Permafrost can be protected by soil shading through vegetation as it reduces the amount of solar energy available for thawing. Regional climate can be affected by a reduction in surface albedo as more energy is available for atmospheric and soil heating. Here, we compared the shortwave radiation budget of two common Arctic tundra vegetation types dominated by dwarf shrubs (Betula nana) and wet sedges (Eriophorum angustifolium) in North-East Siberia. We measured time series of the shortwave and longwave radiation budget above the canopy and transmitted radiation below the canopy. Additionally, we quantified soil temperature and heat flux as well as active layer thickness. The mean growing season albedo of dwarf shrubs was 0.15 ± 0.01, for sedges it was higher (0.17 ± 0.02). Dwarf shrub transmittance was 0.36 ± 0.07 on average, and sedge ... : Environmental Science & Technology, 13 (2016) ...