Spatial Variability of CO 2 Emissions from Newly Exposed Paraglacial Soils at a Glacier Retreat Zone on King George Island, Maritime Antarctica

• Published in: Permafrost and Periglacial Processes
• Main Authors: Thomazini, André, Teixeira, Daniel De Bortoli, Turbay, Caio Vinícius Gabrig, La Scala, Newton, Schaefer, Carlos Ernesto G. R., Mendonça, Eduardo De Sá
• Other Authors: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, Conselho Nacional de Desenvolvimento Científico e Tecnológico
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2014
• Subjects: Antarc*; Antarctic; Antarctica; King George Island; permafrost; Permafrost and Periglacial Processes
• Online Access: http://dx.doi.org/10.1002/ppp.1818; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1002%2Fppp.1818; https://onlinelibrary.wiley.com/doi/pdf/10.1002/ppp.1818

ABSTRACT Thawed soils in Antarctica represent organic carbon (C) reservoirs with great potential to increase the net losses of CO 2 to the atmosphere under climate change scenarios. This study spatially zones CO 2 emissions from soil and vegetation along a transect in front of the retreating margin of Ecology Glacier in Admiralty Bay, King George Island, South Shetlands, near the Polish Antarctic station Henryk Arctowski. Two experiments were carried out to determine soil respiration: (1) a transect of 150 measuring points spaced 1 m apart, statistically analysed with split moving windows, identified three regions with different patterns of CO 2 emissions; (2) a survey with three grids containing 60 sampling points, with a minimum distance between points of 0.30 m, totalling 2.7 × 1.5 m, in each of the identified locations. The survey showed that CO 2 emission rates decreased (from 2.38 to 0.00 µmol m ‐2 s ‐1 ) and soil temperature at 5 cm depth increased (from 1.9 to 7°C) near the glacier. The site farthest from the glacier provided an emission 3.5 times higher than the closest site. The spatial variability of CO 2 emissions decreased with distance from the glacier. Soil development and vegetation are identified as key drivers of CO 2 emissions. Soil formation and vegetation growth increased with longer exposure since deglaciation, leading to enhanced homogeneity of CO 2 emissions, independent of permafrost occurrence and stability. Copyright © 2014 John Wiley & Sons, Ltd.