Distributions and sources of dissolved iron in the polar oceans
PhD ceremony: Mr. M.B. Klunder, 11.00 uur, Academiegebouw, Broerstraat 5, Groningen
Dissertation: Distributions and sources of dissolved iron in the polar oceans
Promotor(s): prof. H.J.W. de Baar
Faculty: Mathematics and Natural Sciences
The availability of iron is very important for algal growth in the ocean, thus for the entire ocean food web. Maarten Klunder investigated the distribution and sources of dissolved iron in the Polar Oceans. Iron is measured in high resolution in water samples divided over the entire depth of the ocean. In the Arctic Ocean it appeared that iron from the Siberian rivers is transported with the Transpolar Drift and reaches the middle of the Arctic Ocean. Further towards the Canadian side, iron concentrations decrease the concentration is determined by melting ice and biological factors. In the deep Arctic Ocean, hydrothermal vents are an important source of iron. In the Makarov Basin, a low iron concentration is attributed to the lack of input sources and the influence of organic ligands. In the Southern Ocean an inverse relation between fluorescence, indicative for algal growth, and dissolved iron is found. The common pattern of increasing iron concentrations towards continental shelves is not present in the Weddell Sea, likely as a result of the ice sheet extending far beyond the continent. Local sources of iron are dust deposition at the surface and hydrothermal vents at depth. At the zero meridian the nitrate:phosphate and nitrate:silicate uptake increases with dissolved iron whereas in the Western Weddell Sea there was no relation. This can be explained by the significantly larger algae at the zero meridian, for which there is a much larger effect of iron on the nutrient uptake and thus on the growth.
Last modified: | 13 March 2020 01.00 a.m. |
More news
-
23 April 2024
Nine MSCA Doctoral Network grants for FSE researchers
Nine researchers of the Faculty of Science and Engineering have received a Horizon Europe Marie Sklodowska Curie Doctoral Network grant.
-
22 April 2024
Charissa Roossien secures JTF subsidy to develop Health Tracker
Dr. Charissa Roossien (ENTEG) has successfully secured a Just Transition Fund (JTF) subsidy of 1.8 million euros to develop a Health Tracker for reliable respiratory and metabolic analysis.
-
16 April 2024
UG signs Barcelona Declaration on Open Research Information
In a significant stride toward advancing responsible research assessment and open science, the University of Groningen has officially signed the Barcelona Declaration on Open Research Information.