Anna Ekberg. Foto.

Anna Ekberg

Projektkoordinator

Anna Ekberg. Foto.

Isoprene emission from Sphagnum species occupying different growth positions above the water table

Författare

  • Anna Ekberg
  • Almut Arneth
  • Thomas Holst

Summary, in English

Isoprene emission from Sphagnum species naturally growing at different positions above the water table were measured in a subarctic peatland and at monoliths from a temperate bog. Our objectives were to investigate (1) whether emission rates were species and/or moisture dependent, and (2) whether short-term temperature history had an influence on emission capacity. We expected greater emission capacities in moist than dry growing conditions, and from species adapted to wet habitats. We also expected that higher emission capacities would be found in response to elevated temperatures. Average peak growing season isoprene emission capacities (standardized to 20 degrees C and PAR 1000 mu mol m(-2) s(-1)) at the subarctic site were 106 and 74 mu g C m(-2) h(-1) from a S. balticum wet lawn and a S. balticum dry hummock/palsa, respectively. Emission capacities correlated strongly with gross primary productivity (GPP) and the average air temperature of the 48 hours prior to measurement (T-48), but the effect of T-48 seemed to be partly masked by the influence of GPP when moisture was not limiting. The laboratory experiments suggested that a typical hummock species, S. rubellum had higher capacity for isoprene emission than a typical lawn species S. magellanicum. Instantaneous emission rates increased with temperature, but no effect of temperature history was discernible. Sphagnum mosses are known to emit substantial amounts of isoprene, but in this study we also showed significant inter-species differences in emission capacity. The results imply that climate change induced alterations of peatland hydrology may change the total ecosystem isoprene source strength, as individual species adapt to new growth conditions or as a consequence of species succession.

Avdelning/ar

  • Institutionen för naturgeografi och ekosystemvetenskap
  • MERGE - ModElling the Regional and Global Earth system
  • BECC - Biodiversity and Ecosystem services in a Changing Climate

Publiceringsår

2011

Språk

Engelska

Sidor

47-59

Publikation/Tidskrift/Serie

Boreal Environment Research: An International Interdisciplinary Journal

Volym

16

Issue

1

Dokumenttyp

Artikel i tidskrift

Förlag

Finnish Zoological and Botanical Publishing Board

Ämne

  • Physical Geography

Status

Published

ISBN/ISSN/Övrigt

  • ISSN: 1239-6095