Assessing seasonal primary production in Andvord Bay, Antarctica
The western Antarctic Peninsula is rapidly warming and its high-latitude fjord ecosystems are expected to be highly sensitive to climate warming (Weslawski et al. 2011; Cook et al. 2016). As the region continues to change, understanding the current nutrient budget will allow for better predictions o...
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ftcdlib:qt2kf1393g 2023-05-15T13:52:31+02:00 Assessing seasonal primary production in Andvord Bay, Antarctica Ekern, Lindsey 70 2017-01-01 application/pdf http://www.escholarship.org/uc/item/2kf1393g en eng eScholarship, University of California http://www.escholarship.org/uc/item/2kf1393g qt2kf1393g public Ekern, Lindsey. (2017). Assessing seasonal primary production in Andvord Bay, Antarctica. UC San Diego: Oceanography. Retrieved from: http://www.escholarship.org/uc/item/2kf1393g Biological oceanography Chemical oceanography Andvord Bay Antarctica Fjord Nitrate Nutrients Primary Production dissertation 2017 ftcdlib 2017-12-22T23:51:38Z The western Antarctic Peninsula is rapidly warming and its high-latitude fjord ecosystems are expected to be highly sensitive to climate warming (Weslawski et al. 2011; Cook et al. 2016). As the region continues to change, understanding the current nutrient budget will allow for better predictions of ecosystem response at all levels of the food web to variable future conditions. Analysis from two synoptic transects along Andvord Bay, bracketing the 2015-2016 austral summer, allows for primary production to be assessed through the depletion of dissolved inorganic nutrients, nitrate and silicate. Andvord Bay is a quiescent system that can experience surface nutrient replenishment during katabatic wind events otherwise sustaining favorable growth conditions throughout an extended growth season. The high concentration of surface nitrate and minimal presence of reduced nitrogen species in spring suggests new production dominates the early season while an observed four-fold increase in ammonium would support late season recycled production. Silicate depletion indicates 25-68% of the primary production in Andvord Bay was from diatom growth from December 2015 to April 2016. Modifications were made to the nutrient drawdown method for primary production estimation to adapt to conditions unique to the Andvord Bay region, replacing the baseline winter water requirement and adapting the growth periods. Applied, this method yields reasonable, conservative estimates for net community new production indicating greater production inside the fjord than the outside waters of the Gerlache Strait and supporting the hypotheses that fjords in the WAP are hot-spots of productivity. Doctoral or Postdoctoral Thesis Antarc* Antarctic Antarctic Peninsula Antarctica University of California: eScholarship Andvord ENVELOPE(-62.616,-62.616,-64.833,-64.833) Andvord Bay ENVELOPE(-62.650,-62.650,-64.833,-64.833) Antarctic Antarctic Peninsula Austral Gerlache ENVELOPE(99.033,99.033,-66.500,-66.500) Gerlache Strait ENVELOPE(-62.333,-62.333,-64.500,-64.500) |
institution |
Open Polar |
collection |
University of California: eScholarship |
op_collection_id |
ftcdlib |
language |
English |
topic |
Biological oceanography Chemical oceanography Andvord Bay Antarctica Fjord Nitrate Nutrients Primary Production |
spellingShingle |
Biological oceanography Chemical oceanography Andvord Bay Antarctica Fjord Nitrate Nutrients Primary Production Ekern, Lindsey Assessing seasonal primary production in Andvord Bay, Antarctica |
topic_facet |
Biological oceanography Chemical oceanography Andvord Bay Antarctica Fjord Nitrate Nutrients Primary Production |
description |
The western Antarctic Peninsula is rapidly warming and its high-latitude fjord ecosystems are expected to be highly sensitive to climate warming (Weslawski et al. 2011; Cook et al. 2016). As the region continues to change, understanding the current nutrient budget will allow for better predictions of ecosystem response at all levels of the food web to variable future conditions. Analysis from two synoptic transects along Andvord Bay, bracketing the 2015-2016 austral summer, allows for primary production to be assessed through the depletion of dissolved inorganic nutrients, nitrate and silicate. Andvord Bay is a quiescent system that can experience surface nutrient replenishment during katabatic wind events otherwise sustaining favorable growth conditions throughout an extended growth season. The high concentration of surface nitrate and minimal presence of reduced nitrogen species in spring suggests new production dominates the early season while an observed four-fold increase in ammonium would support late season recycled production. Silicate depletion indicates 25-68% of the primary production in Andvord Bay was from diatom growth from December 2015 to April 2016. Modifications were made to the nutrient drawdown method for primary production estimation to adapt to conditions unique to the Andvord Bay region, replacing the baseline winter water requirement and adapting the growth periods. Applied, this method yields reasonable, conservative estimates for net community new production indicating greater production inside the fjord than the outside waters of the Gerlache Strait and supporting the hypotheses that fjords in the WAP are hot-spots of productivity. |
format |
Doctoral or Postdoctoral Thesis |
author |
Ekern, Lindsey |
author_facet |
Ekern, Lindsey |
author_sort |
Ekern, Lindsey |
title |
Assessing seasonal primary production in Andvord Bay, Antarctica |
title_short |
Assessing seasonal primary production in Andvord Bay, Antarctica |
title_full |
Assessing seasonal primary production in Andvord Bay, Antarctica |
title_fullStr |
Assessing seasonal primary production in Andvord Bay, Antarctica |
title_full_unstemmed |
Assessing seasonal primary production in Andvord Bay, Antarctica |
title_sort |
assessing seasonal primary production in andvord bay, antarctica |
publisher |
eScholarship, University of California |
publishDate |
2017 |
url |
http://www.escholarship.org/uc/item/2kf1393g |
op_coverage |
70 |
long_lat |
ENVELOPE(-62.616,-62.616,-64.833,-64.833) ENVELOPE(-62.650,-62.650,-64.833,-64.833) ENVELOPE(99.033,99.033,-66.500,-66.500) ENVELOPE(-62.333,-62.333,-64.500,-64.500) |
geographic |
Andvord Andvord Bay Antarctic Antarctic Peninsula Austral Gerlache Gerlache Strait |
geographic_facet |
Andvord Andvord Bay Antarctic Antarctic Peninsula Austral Gerlache Gerlache Strait |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica |
op_source |
Ekern, Lindsey. (2017). Assessing seasonal primary production in Andvord Bay, Antarctica. UC San Diego: Oceanography. Retrieved from: http://www.escholarship.org/uc/item/2kf1393g |
op_relation |
http://www.escholarship.org/uc/item/2kf1393g qt2kf1393g |
op_rights |
public |
_version_ |
1766256827444494336 |