Astrid Fischer

Astrid Fischer
Plankton Analyst

Role:

Plankton analyst: To carry out plankton analysis of Atlantic Continous Plankton Recorder (CPR) samples, to enter data on the CPR console, to archive samples accurately. Curator of the plankton archive of SAHFOS. Assist with the molecular analysis of cnidarian material of the CPR samples.


Background, qualifications and professional membership:

PhD 'A compartmental analysis of the kinetics of iron uptake by Antarctic diatoms' Awarded June 2009. Involved use of radiotracer techniques, chromatographic SepPak C18 cartridge separations with functional organic ligands, flow-cytometry and voltammetric low-level Fe analysis and use of auto-analyser to measure nutrients.

MSc in Chemical Technology: Biotechnology, Average grade: 7. Awarded September 1999.

BSc in Chemical Technology: Process technology and Environmental Technology. Average grade: 7.3. Awarded  July 1997.

VWO (Equivalent to A-levels): Dutch, English, Mathematics, Physics, Chemistry and Economics. Average grade: 7.7. Awarded July 1992.

Additional courses

Management, Royal Netherlands Chemical Society (2002)

Presentation and advice, Royal Netherlands Chemical Society (2002)

Speciation and Bioavailability, Wageningen University and Research Centre (2002)

Health physics level 3, Delft University of Technology (2002)

Oceanography, University of Groningen (2000)

Technical writing in English, Delft University of Technology (2000)


Research Interests:

Climate change in the marine environment. I have helped to set up the Marine Climate Change Impacts Partnership in the UK and have since worked with Prof Chris Reid on various reports outlining the impacts of marine climate change. Recently I have contributed to a major report on the impacts of the oceans on climate change, which has been published in Advances in Marine Biology, which outlines the possible feedback mechanisms in the oceans that can decrease or accelerate climate change.

 

Nutrient limitation in plankton communities. I have just completed my PhD which looked into the kinetics of iron speciation in seawater, with the effects of iron limitation on two Antarctic diatoms. I also studied the impacts of UV light on these kinetics. In the so called High- Nutrient Low Chlorophyll regions of the oceans, plankton blooms are limited by the availability of iron. Iron is hardly soluble in seawater and the major part of iron is in its complexed form (bound to organic ligands) and may not be accessible to plankton.

 

Ocean acidification. As a result of climate change, the oceans have been taking up a major part of our CO2 emissions to the atmosphere and are therefore getting more acidic. This is a major threat to our vulnerable ecosystem, as the change is happening quickly and they may not have time to adapt to the new circumstances.

 

Environmental change. There have been many changes observed in the marine environment, that are related to climate change, but that may have major implications to our living environment. For example, a Pacific diatom, Neodenticula sp. was observed in the Atlantic for the first time in 800,000 years, which indicates the opening of the Arctic passage. Also, some plankton species have shifted northwards by a 1000 km. The impact of these changes is still poorly understood.


Publications:

Peer-reviewed publications

  • A C Fischer, M J A  Rijkenberg, J J Kroon, T G Verburg, L J A Gerringa, K R   Timmermans, M J M Roest, H Th Wolterbeek., Compartmental kinetic analysis of iron uptake by Chaetoceros brevis and Thalassiosira sp. In preparation.
  • P C Reid, A C Fischer, E Lewis-Brown, M P Meredith, M Sparrow, A J Andersson, A Antia, N R Bates, U Bathmann, G Beaugrand, H Brix, S Dye, M Edwards, T Furevik, R Gangstø, H Hátún, R R Hopcroft, M Kendall, S Kasten, R Keeling, C Le Quéré, F T Mackenzie, G Malin, C Mauritzen, J Olafsson, C Paull, E Rignot, K Shimada, M Vogt , C Wallace, Z Wang, R Washington. The Impacts of the Oceans on Climate Change Advances in Marine Biology (2009) Vol. 56, p. 1-150
  • A C Fischer, A Compartmental Analysis of Iron Uptake by Two Antarctic Diatoms. PhD Thesis. ISBN: 978-1-60750-016-2, May 2009, IOS Press, Delft, The Netherlands, http://repository.tudelft.nl/view/ir/uuid%3Aec06bb8b-afaa-4ea4-8f32-cc1919684097/
  • M J A Rijkenberg, L J A Gerringa, K R Timmermans, A C Fischer, J J Kroon, A G J Buma, H Th Wolterbeek, H J W de Baar, Enhancement of the reactive iron pool by marine diatoms. Marine Chemistry (2008) Vol. 190, p. 29-44
  • A C Fischer, J J Kroon, T G Verburg, T Teunissen, H Th Wolterbeek, On the relevance of iron adsorption to container materials in small-volume experiments on iron marine chemistry: 55Fe-aided assessment of capacity, affinity and kinetics. Marine Chemistry (2007) Vol. 107(4), p. 533-546
  • A C Fischer, T G Verburg, H Th Wolterbeek. Off-line chromatographic assessment of Fe(II) in seawater. Talanta (2007) Vol. 72 (1), p. 54-59
  • A C Fischer, O M Steinebach, K R Timmermans and H Th Wolterbeek; A method for the destruction and analysis of biogenic silica in two Antarctic diatom species: Thalassiosira sp. and Chaetoceros brevis. Journal of Applied Phycology (2007), Vol. 19 (1), p. 71-77
  • A C Fischer, H Th Wolterbeek, J J Kroon, L J A Gerringa, K R Timmermans, J T van Elteren and T Teunissen; On the use of iron radio-isotopes to study iron speciation kinetics in seawater: a column separation and off-line counting approach. The Science of the Total Environment (2006) vol. 362, p. 242-258
  • M J A Rijkenberg, A C Fischer, J J Kroon, L J A Gerringa, K R Timmermans, H Th Wolterbeek and H J W De Baar; The influence of UV irradiation on the photoreduction of iron in the Southern Ocean. Marine Chemistry (2005) vol. 93, p.119-129

Other publications

  • A C Fischer and C H Mahn, 'Material Properties of Stainless Steel: What does it mean for Stencil Manufacturers?', http://www.datumalloys.com/new/files/products/95.pdf (2007)
  • Draft Business Plan for the Marine Climate Change Impacts Partnership (2005)
  • M J A Rijkenberg, L J A Gerringa, K J Timmermans, A C Fischer, V Carolus, L R M Maas, P J Neale and H J W de Baar; The photoreduction of iron in seawater. Abstract, EGS - AGU - EUG Joint Assembly, Nice, France, April 2003
  • A C Fischer, J J Kroon, L Gerringa, A G J Buma, J T van Elteren and J J M de Goeij; Measuring the effect of UV radiation on iron speciation in filtered seawater using the radioisotopes 55Fe and 59Fe. In: Circumpolar Journal 2001 volume 16. Antarctica symposium SCAR-CAO(Amsterdam, 12-04-2001), p. 37.
  • M Rijkenberg, A C Fischer, L Gerringa, K Kroon, K Timmermans, A Buma and H de Baar; The influence of enhanced UV radiation on the diel cycle of iron photoreduction in the Southern Ocean. In: Circumpolar Journal 2001 volume 16. Antarctica symposium SCAR-CAO(Amsterdam, 12-04-2001), p. 41.
  • L J A Gerringa, K R Timmermans, P Croot, B van der Wagt, P Laan, H J W de Baar, M J A Rijkenberg, M Boye, A G J Buma, E Achterberg, A Bowie, S El Naggar, A C Fischer and J J Kroon; The influence of UV on Fe chemistry and peroxide formation in relation to Fe-availability for phytoplankton. In: The Expeditions ANTARKTIS XVIII/1-2 of the Research Vessel "Polarstern" in 2000. p. 41-48. ISBN: 1618-3193.
  • M Rijkenberg, A Fischer, H de Baar, L Gerringa, K Kroon, A Buma, K Timmermans, B Wolterbeek, M Veldhuis, H van Elteren, P Croot, P Laan and M Boye; Effects of UV radiation on iron speciation and its availability for phytoplankton. In: The Expeditions ANTARKTIS XVIII/1-2 of the Research Vessel "Polarstern" in 2000. p. 139-144. ISBN: 1618-3193.

Roles on external bodies / national / international responsibilities:

n/a


Links:

http://repository.tudelft.nl/view/ir/uuid%3Aec06bb8b-afaa-4ea4-8f32-cc1919684097/