Regional impacts of iron-light colimitation in a global biogeochemical model
Laboratory and field studies have revealed that iron has multiple roles in phytoplankton physiology, with particular importance for light-harvesting cellular machinery. However, although iron-limitation is explicitly included in numerous biogeochemical/ecosystem models, its implementation varies, an...
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ftdoajarticles:oai:doaj.org/article:ad55d7534ccf46aaaf39ae1dab90459c 2023-05-15T18:25:44+02:00 Regional impacts of iron-light colimitation in a global biogeochemical model E. D. Galbraith A. Gnanadesikan J. P. Dunne M. R. Hiscock 2010-03-01T00:00:00Z https://doaj.org/article/ad55d7534ccf46aaaf39ae1dab90459c EN eng Copernicus Publications http://www.biogeosciences.net/7/1043/2010/bg-7-1043-2010.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 https://doaj.org/article/ad55d7534ccf46aaaf39ae1dab90459c Biogeosciences, Vol 7, Iss 3, Pp 1043-1064 (2010) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2010 ftdoajarticles 2022-12-31T01:23:01Z Laboratory and field studies have revealed that iron has multiple roles in phytoplankton physiology, with particular importance for light-harvesting cellular machinery. However, although iron-limitation is explicitly included in numerous biogeochemical/ecosystem models, its implementation varies, and its effect on the efficiency of light harvesting is often ignored. Given the complexity of the ocean environment, it is difficult to predict the consequences of applying different iron limitation schemes. Here we explore the interaction of iron and nutrient cycles in an ocean general circulation model using a new, streamlined model of ocean biogeochemistry. Building on previously published parameterizations of photoadaptation and export production, the Biogeochemistry with Light Iron Nutrients and Gasses (BLING) model is constructed with only four explicit tracers but including macronutrient and micronutrient limitation, light limitation, and an implicit treatment of community structure. The structural simplicity of this computationally-inexpensive model allows us to clearly isolate the global effect that iron availability has on maximum light-saturated photosynthesis rates vs. the effect iron has on photosynthetic efficiency. We find that the effect on light-saturated photosynthesis rates is dominant, negating the importance of photosynthetic efficiency in most regions, especially the cold waters of the Southern Ocean. The primary exceptions to this occur in iron-rich regions of the Northern Hemisphere, where high light-saturated photosynthesis rates allow photosynthetic efficiency to play a more important role. In other words, the ability to efficiently harvest photons has little effect in regions where light-saturated growth rates are low. Additionally, we speculate that the phytoplankton cells dominating iron-limited regions tend to have relatively high photosynthetic efficiency, due to reduced packaging effects. If this speculation is correct, it would imply that natural communities of iron-stressed ... Article in Journal/Newspaper Southern Ocean Directory of Open Access Journals: DOAJ Articles Southern Ocean |
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topic |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
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Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 E. D. Galbraith A. Gnanadesikan J. P. Dunne M. R. Hiscock Regional impacts of iron-light colimitation in a global biogeochemical model |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
description |
Laboratory and field studies have revealed that iron has multiple roles in phytoplankton physiology, with particular importance for light-harvesting cellular machinery. However, although iron-limitation is explicitly included in numerous biogeochemical/ecosystem models, its implementation varies, and its effect on the efficiency of light harvesting is often ignored. Given the complexity of the ocean environment, it is difficult to predict the consequences of applying different iron limitation schemes. Here we explore the interaction of iron and nutrient cycles in an ocean general circulation model using a new, streamlined model of ocean biogeochemistry. Building on previously published parameterizations of photoadaptation and export production, the Biogeochemistry with Light Iron Nutrients and Gasses (BLING) model is constructed with only four explicit tracers but including macronutrient and micronutrient limitation, light limitation, and an implicit treatment of community structure. The structural simplicity of this computationally-inexpensive model allows us to clearly isolate the global effect that iron availability has on maximum light-saturated photosynthesis rates vs. the effect iron has on photosynthetic efficiency. We find that the effect on light-saturated photosynthesis rates is dominant, negating the importance of photosynthetic efficiency in most regions, especially the cold waters of the Southern Ocean. The primary exceptions to this occur in iron-rich regions of the Northern Hemisphere, where high light-saturated photosynthesis rates allow photosynthetic efficiency to play a more important role. In other words, the ability to efficiently harvest photons has little effect in regions where light-saturated growth rates are low. Additionally, we speculate that the phytoplankton cells dominating iron-limited regions tend to have relatively high photosynthetic efficiency, due to reduced packaging effects. If this speculation is correct, it would imply that natural communities of iron-stressed ... |
format |
Article in Journal/Newspaper |
author |
E. D. Galbraith A. Gnanadesikan J. P. Dunne M. R. Hiscock |
author_facet |
E. D. Galbraith A. Gnanadesikan J. P. Dunne M. R. Hiscock |
author_sort |
E. D. Galbraith |
title |
Regional impacts of iron-light colimitation in a global biogeochemical model |
title_short |
Regional impacts of iron-light colimitation in a global biogeochemical model |
title_full |
Regional impacts of iron-light colimitation in a global biogeochemical model |
title_fullStr |
Regional impacts of iron-light colimitation in a global biogeochemical model |
title_full_unstemmed |
Regional impacts of iron-light colimitation in a global biogeochemical model |
title_sort |
regional impacts of iron-light colimitation in a global biogeochemical model |
publisher |
Copernicus Publications |
publishDate |
2010 |
url |
https://doaj.org/article/ad55d7534ccf46aaaf39ae1dab90459c |
geographic |
Southern Ocean |
geographic_facet |
Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Biogeosciences, Vol 7, Iss 3, Pp 1043-1064 (2010) |
op_relation |
http://www.biogeosciences.net/7/1043/2010/bg-7-1043-2010.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 https://doaj.org/article/ad55d7534ccf46aaaf39ae1dab90459c |
_version_ |
1766207376146300928 |