Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons
We have examined organismic responses of Dryas octopetala to simulated changes in the summer climate at four tundra sites as part of the International Tundra Experiment (ITEX). Our study sites are located in the High Arctic, on Svalbard, Norway, in the Low Arctic at Abisko, Sweden, and at Toolik Lak...
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ftumanchesterpub:oai:pure.atira.dk:publications/b47aea06-490a-4185-b690-e426cd3bec2b 2024-06-23T07:44:52+00:00 Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons Welker, J. M. Molau, U. Parsons, A. N. Robinson, C. H. Wookey, P. A. 1997 https://research.manchester.ac.uk/en/publications/b47aea06-490a-4185-b690-e426cd3bec2b http://://000071285300007 eng eng https://research.manchester.ac.uk/en/publications/b47aea06-490a-4185-b690-e426cd3bec2b info:eu-repo/semantics/restrictedAccess Welker , J M , Molau , U , Parsons , A N , Robinson , C H & Wookey , P A 1997 , ' Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons ' , Global Change Biology , vol. 3 , pp. 61-73 . < http://://000071285300007 > article 1997 ftumanchesterpub 2024-06-04T00:17:32Z We have examined organismic responses of Dryas octopetala to simulated changes in the summer climate at four tundra sites as part of the International Tundra Experiment (ITEX). Our study sites are located in the High Arctic, on Svalbard, Norway, in the Low Arctic at Abisko, Sweden, and at Toolik Lake, Alaska, USA and our temperate alpine site is at Niwot Ridge, Colorado, USA. These sites represent a range of tundra temperature and precipitation regimes, being generally cold and dry in the High Arctic and warmer and wetter at Toolik Lake and Niwot Ridge. Results from our studies indicate organismic attributes such as flowering shoot length varies by 30% between low and high arctic populations and that experimental warming results in significant increases in shoot height at three of four sites. We find that phenological developement of Dryas is accelerated under experimentally warmed conditions which corresponds with a lengthening of the growing season in autumn, greater degrees of seed set and a higher likelihood of colonization of bare ground. We also observe that Dryas dominated ecosystems which are exposed to experimental manipulations are capable of exhibiting net carbon sequestration in late autumn, and that Dryas photosynthesis and green leaf biomass is significantly greater under warmer as opposed to ambient temperature conditions. Dryas leaf nitrogen is also significantly lowered under warmer conditions resulting in senescent leaves having a higher C:N ratio than those under ambient conditions. Together these findings indicate that Dryas phenology and carbon flux may be altered to the greatest degree in spring and again in autumn by higher summer temperatures and that simultaneously both positive and negative feedback effects may result from changes in plant and ecosystem performance. Article in Journal/Newspaper Abisko Arctic Dryas octopetala Svalbard Tundra Alaska The University of Manchester: Research Explorer Abisko ENVELOPE(18.829,18.829,68.349,68.349) Arctic Norway Svalbard |
institution |
Open Polar |
collection |
The University of Manchester: Research Explorer |
op_collection_id |
ftumanchesterpub |
language |
English |
description |
We have examined organismic responses of Dryas octopetala to simulated changes in the summer climate at four tundra sites as part of the International Tundra Experiment (ITEX). Our study sites are located in the High Arctic, on Svalbard, Norway, in the Low Arctic at Abisko, Sweden, and at Toolik Lake, Alaska, USA and our temperate alpine site is at Niwot Ridge, Colorado, USA. These sites represent a range of tundra temperature and precipitation regimes, being generally cold and dry in the High Arctic and warmer and wetter at Toolik Lake and Niwot Ridge. Results from our studies indicate organismic attributes such as flowering shoot length varies by 30% between low and high arctic populations and that experimental warming results in significant increases in shoot height at three of four sites. We find that phenological developement of Dryas is accelerated under experimentally warmed conditions which corresponds with a lengthening of the growing season in autumn, greater degrees of seed set and a higher likelihood of colonization of bare ground. We also observe that Dryas dominated ecosystems which are exposed to experimental manipulations are capable of exhibiting net carbon sequestration in late autumn, and that Dryas photosynthesis and green leaf biomass is significantly greater under warmer as opposed to ambient temperature conditions. Dryas leaf nitrogen is also significantly lowered under warmer conditions resulting in senescent leaves having a higher C:N ratio than those under ambient conditions. Together these findings indicate that Dryas phenology and carbon flux may be altered to the greatest degree in spring and again in autumn by higher summer temperatures and that simultaneously both positive and negative feedback effects may result from changes in plant and ecosystem performance. |
format |
Article in Journal/Newspaper |
author |
Welker, J. M. Molau, U. Parsons, A. N. Robinson, C. H. Wookey, P. A. |
spellingShingle |
Welker, J. M. Molau, U. Parsons, A. N. Robinson, C. H. Wookey, P. A. Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons |
author_facet |
Welker, J. M. Molau, U. Parsons, A. N. Robinson, C. H. Wookey, P. A. |
author_sort |
Welker, J. M. |
title |
Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons |
title_short |
Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons |
title_full |
Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons |
title_fullStr |
Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons |
title_full_unstemmed |
Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons |
title_sort |
responses of dryas octopetala to itex environmental manipulations: a synthesis with circumpolar comparisons |
publishDate |
1997 |
url |
https://research.manchester.ac.uk/en/publications/b47aea06-490a-4185-b690-e426cd3bec2b http://://000071285300007 |
long_lat |
ENVELOPE(18.829,18.829,68.349,68.349) |
geographic |
Abisko Arctic Norway Svalbard |
geographic_facet |
Abisko Arctic Norway Svalbard |
genre |
Abisko Arctic Dryas octopetala Svalbard Tundra Alaska |
genre_facet |
Abisko Arctic Dryas octopetala Svalbard Tundra Alaska |
op_source |
Welker , J M , Molau , U , Parsons , A N , Robinson , C H & Wookey , P A 1997 , ' Responses of Dryas octopetala to ITEX environmental manipulations: a synthesis with circumpolar comparisons ' , Global Change Biology , vol. 3 , pp. 61-73 . < http://://000071285300007 > |
op_relation |
https://research.manchester.ac.uk/en/publications/b47aea06-490a-4185-b690-e426cd3bec2b |
op_rights |
info:eu-repo/semantics/restrictedAccess |
_version_ |
1802649310317248512 |