The importance of winter in annual ecosystem respiration in the High Arctic: effects of snow depth in two vegetation types

Polar research

Bo Elberling¹  Elisabeth J. Cooper²  Elke Morgner³  Ditte Strebel³ 

[1] Department of Arctic and Marine Biology, University of Tromsø, NO-9037 Tromsø, Norway;Department of Geography and Geology, University of Copenhagen, Øster Voldgade 10, DK-1350 Copenhagen K., Denmark;Department of Arctic Biology, University Centre in Svalbard, PO Box 156, NO-9171 Longyearbyen, Norway;Department of Arctic and Marine Biology, University of Tromsø, NO-9037 Tromsø, NorwayCorrespondence

关键词: Climate change;    CO2;    precipitation;    snow fence;    Svalbard;    tundra vegetation;   

DOI  :  10.1111/j.1751-8369.2010.00151.x

学科分类：自然科学（综合）

来源: Co-Action Publishing

【 摘 要 】

Winter respiration in snow-covered ecosystems strongly influences annual carbon cycling, underlining the importance of processes related to the timing and quantity of snow. Fences were used to increase snow depth from 30 to 150 cm, and impacts on respiration were investigated in heath and mesic meadow, two common vegetation types in Svalbard. We manually measured ecosystem respiration from July 2007 to July 2008 at a temporal resolution greater than previously achieved in the High Arctic (campaigns: summer, eight; autumn, six; winter, 17; spring, nine). Moisture contents of unfrozen soil and soil temperatures throughout the year were also recorded. The increased snow depth resulted in significantly higher winter soil temperatures and increased ecosystem respiration. A temperature–efflux model explained most of the variation of observed effluxes: meadows, 94 (controls) and 93% (fences); heaths, 84 and 77%, respectively. Snow fences increased the total non-growing season efflux from 70 to 92 (heaths) and fr...

【 授权许可】

CC BY-NC