The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope
Thesis (M.S.) University of Alaska Fairbanks, 2015 Terrestrial organic matter (OMterr) can function as a food source for Arctic marine consumers, though the relative contribution of OMterr to the structure and efficiency of marine food webs compared to marine production is unclear. Forecasted increa...
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ftunivalaska:oai:scholarworks.alaska.edu:11122/5583 2023-05-15T15:02:18+02:00 The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope Bell, Lauren Iken, Katrin Okkonen, Steve Wooller, Matthew Bluhm, Bodil 2015-05 http://hdl.handle.net/11122/5583 en_US eng http://hdl.handle.net/11122/5583 Marine Science and Limnology Thesis ms 2015 ftunivalaska 2023-02-23T21:36:28Z Thesis (M.S.) University of Alaska Fairbanks, 2015 Terrestrial organic matter (OMterr) can function as a food source for Arctic marine consumers, though the relative contribution of OMterr to the structure and efficiency of marine food webs compared to marine production is unclear. Forecasted increases in OMterr inputs to the Arctic Beaufort Sea necessitate a better understanding of the proportional contribution of this organic matter source to the trophic structure of marine communities. This study investigated the relative ecological importance of OMterr across the Beaufort Sea shelf and slope by examining differences in community trophic structure concurrent with variation in terrestrial versus marine organic matter influence. Hydrogen stable isotope ratios (δD) of surface water, surface sediment particulate organic matter (sPOM), and selected benthic consumers were used as an exploratory assessment of freshwater and OMterr distribution in the Beaufort Sea. δD values of surface water confirmed the widespread influence of Canada's Mackenzie River plume across the Beaufort Sea; however, δD values of terrestrial and marine production were not sufficiently distinguishable to differentiate organic matter sources in consumers. Carbon stable isotope ratios (δ¹³C values) of pelagic particulate organic matter (pPOM) and marine consumers confirmed a significant decrease in OMterr presence and utilization by consumers with increasing distance from the Mackenzie River outflow. Food web length, based on the nitrogen stable isotope ratios (δ¹⁵N values) of marine consumers, was longer closer to the Mackenzie River outflow both in shelf and slope locations due to relatively higher δ¹⁵N values of pelagic and benthic primary consumers. The absence of macrofaunal consumers at the lowest trophic levels of OMterr-influenced food webs was interpreted to result from the prior metabolic turnover of OMterr by the microbial loop, which was not sampled in this study. The inferred presence of strong microbial processing of OMterr in ... Thesis Arctic Beaufort Sea Mackenzie river Alaska University of Alaska: ScholarWorks@UA Arctic Fairbanks Mackenzie River |
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University of Alaska: ScholarWorks@UA |
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English |
description |
Thesis (M.S.) University of Alaska Fairbanks, 2015 Terrestrial organic matter (OMterr) can function as a food source for Arctic marine consumers, though the relative contribution of OMterr to the structure and efficiency of marine food webs compared to marine production is unclear. Forecasted increases in OMterr inputs to the Arctic Beaufort Sea necessitate a better understanding of the proportional contribution of this organic matter source to the trophic structure of marine communities. This study investigated the relative ecological importance of OMterr across the Beaufort Sea shelf and slope by examining differences in community trophic structure concurrent with variation in terrestrial versus marine organic matter influence. Hydrogen stable isotope ratios (δD) of surface water, surface sediment particulate organic matter (sPOM), and selected benthic consumers were used as an exploratory assessment of freshwater and OMterr distribution in the Beaufort Sea. δD values of surface water confirmed the widespread influence of Canada's Mackenzie River plume across the Beaufort Sea; however, δD values of terrestrial and marine production were not sufficiently distinguishable to differentiate organic matter sources in consumers. Carbon stable isotope ratios (δ¹³C values) of pelagic particulate organic matter (pPOM) and marine consumers confirmed a significant decrease in OMterr presence and utilization by consumers with increasing distance from the Mackenzie River outflow. Food web length, based on the nitrogen stable isotope ratios (δ¹⁵N values) of marine consumers, was longer closer to the Mackenzie River outflow both in shelf and slope locations due to relatively higher δ¹⁵N values of pelagic and benthic primary consumers. The absence of macrofaunal consumers at the lowest trophic levels of OMterr-influenced food webs was interpreted to result from the prior metabolic turnover of OMterr by the microbial loop, which was not sampled in this study. The inferred presence of strong microbial processing of OMterr in ... |
author2 |
Iken, Katrin Okkonen, Steve Wooller, Matthew Bluhm, Bodil |
format |
Thesis |
author |
Bell, Lauren |
spellingShingle |
Bell, Lauren The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope |
author_facet |
Bell, Lauren |
author_sort |
Bell, Lauren |
title |
The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope |
title_short |
The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope |
title_full |
The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope |
title_fullStr |
The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope |
title_full_unstemmed |
The Influence of terrestrial matter in marine food webs of the Beaufort Sea shelf and slope |
title_sort |
influence of terrestrial matter in marine food webs of the beaufort sea shelf and slope |
publishDate |
2015 |
url |
http://hdl.handle.net/11122/5583 |
geographic |
Arctic Fairbanks Mackenzie River |
geographic_facet |
Arctic Fairbanks Mackenzie River |
genre |
Arctic Beaufort Sea Mackenzie river Alaska |
genre_facet |
Arctic Beaufort Sea Mackenzie river Alaska |
op_relation |
http://hdl.handle.net/11122/5583 Marine Science and Limnology |
_version_ |
1766334275137830912 |