207
Sentinel 3 satellite, other satellite sensors as Landsat 7
ETM+, Landsat 8 OLI and Sentinel 2 MSI with higher spatial resolutions of up to 10 m are used. High spatial resolution helps resolve small-scale processes in coastal waters
even though the spectral resolutions of those satellites are not
as high as OLCI’s. For the evaluation of Ocean Color satellite products, in situ biogeochemical samples and optical
measurements of the water and its surface are needed.
However, remote regions such as the Laptev Sea shelf are
strongly undersampled. This study presents unique biogeochemical and hyperspectral radiometric measurements of
several expeditions over the last decade and first match-up
results of in situ vs. satellite data.
4 Phytoplankton in a Changing
Environment – Adaptation Mechanisms
and Ecological Surveys
Jana K. Geuer
1
and Laura Käse
2
1
Alfred Wegener Institute (AWI), Helmholtz Centre for
Polar and Marine Research, P.O. Box 120161, 27570
Bremerhaven, Germany
2
Alfred Wegener Institute (AWI), Helmholtz Centre for
Polar and Marine Research, Biologische Anstalt Helgoland,
Postbox 180, 27483 Helgoland, Germany
4.1 Call for Abstracts
The enormous importance of oceanic primary production is
not only limited to the marine environment but has an equally
great impact on the global atmosphere. Our changing climate
affects the composition of phytoplankton species composition and requires the organisms to adapt to this changing
environment, influencing micronutrient bioavailability and
other biogeochemical parameters. Studies to monitor phytoplankton species composition are as important as are molecular and genetic approaches on understanding adaptation
mechanisms of phytoplankton in regard to changing oceanic
conditions. Studies dealing with different approaches on
monitoring changes in phytoplankton, their impact on the
microbial loop and adapting mechanisms are welcome.
4.2 Abstracts of Oral Presentations
4.2.1 Under Surveillance – Monitoring
Phytoplankton and Hunting Their Traces
Laura Käse
1*
, Jana K. Geuer
2*
, Bernd Krock
2
, Katja Metfies
2
,
Boris Koch
2,3
, Alexandra Kraberg
1
1
Biologische Anstalt Helgoland, Alfred-Wegener-Institute
Helmholtz Centre for Polar and Marine Research,
Kurpromenade 201, 27498 Helgoland, Germany
2
Alfred-Wegener-Institute Helmholtz Centre for Polar
and Marine Research, Am Handelshafen 12, 27570
Bremerhaven, Germany
3
Hochschule Bremerhaven, An der Karlstadt 8, 27568
Bremerhaven, Germany
*corresponding authors: laura.kaese@awi.de, jana.
geuer@awi.de
Keywords: Phytoplankton, Microscopy, Marine ligands,
Domoic acid, Next-generation sequencing
Marine primary production is not only crucial for regulating the atmosphere. Phytoplankton is also an important base
for oceanic food webs. Their species composition depends
on seasonal conditions, predators and micronutrient availability. (1) An existing monitoring system, the so called
“Helgoland Roads time-series”, should be improved by
incorporating different monitoring methods to include so far
underreported pico- and nanoplankton. (2) As molecular
tracer the bioactive ligand domoic acid should be quantified
in seawater from the Atlantic Ocean. Phytoplankton samples
were taken two times per week and cells were counted optically via microscopy. The same samples were used for nextgeneration sequencing. For domoic acid quantification,
seawater was filtered via combusted glass fiber filters
(0.7 μm) and subsequently concentrated via solid phase
extraction. Molecular characterisation was done with
Fourier-transform ion cyclotron resonance mass spectrometry. Quantification was performed using high-pressure liquid
chromatography coupled to mass spectrometry. Microscopic
Utermöhl counting resulted in high abundances of different
small-sized flagellates and cryptophytes. Smaller organisms
included in the picoplankton group could not be distinguished further using this method. Bigger organisms like the
diatom Pseudonitzschia sp. are hardly distinguishable on
species level using this method. Therefore, comparison of
these counts and the regular Helgoland Roads counts with
sequencing data is necessary. Additionally the sequencing
data will give lots of information about the different species
of cryptophytes that were not further distinguished via
microscope. In comparison to that a flow cytometer is going
to be used for automated counting and cell sorting. Domoic
acid’s molecular formula could be detected in most samples.
Additionally, it could be quantified in surface water. Higher
concentrations were measured in the northern hemisphere
(up to 172 pmol L
−1
) compared to the southern hemisphere
(up to 15 pmol L
−1
). This method could potentially be transferred to detect and quantify other relevant target ligands.
4.2.2 NMR-Spectroscopic Study of Dissolved
Organic Matter During a Microalgal Spring
Bloom
Christian Zurhelle
1*
, Julian Mönnich
1
, Jan Tebben
2
and
Tilmann Harder
1,2
1
Faculty of Biology and Chemistry, University of Bremen,
Leobener Straße UFT, D-28359 Bremen, Germany
Appendices
Sentinel 3 satellite, other satellite sensors as Landsat 7
ETM+, Landsat 8 OLI and Sentinel 2 MSI with higher spatial resolutions of up to 10 m are used. High spatial resolution helps resolve small-scale processes in coastal waters
even though the spectral resolutions of those satellites are not
as high as OLCI’s. For the evaluation of Ocean Color satellite products, in situ biogeochemical samples and optical
measurements of the water and its surface are needed.
However, remote regions such as the Laptev Sea shelf are
strongly undersampled. This study presents unique biogeochemical and hyperspectral radiometric measurements of
several expeditions over the last decade and first match-up
results of in situ vs. satellite data.
4 Phytoplankton in a Changing
Environment – Adaptation Mechanisms
and Ecological Surveys
Jana K. Geuer
1
and Laura Käse
2
1
Alfred Wegener Institute (AWI), Helmholtz Centre for
Polar and Marine Research, P.O. Box 120161, 27570
Bremerhaven, Germany
2
Alfred Wegener Institute (AWI), Helmholtz Centre for
Polar and Marine Research, Biologische Anstalt Helgoland,
Postbox 180, 27483 Helgoland, Germany
4.1 Call for Abstracts
The enormous importance of oceanic primary production is
not only limited to the marine environment but has an equally
great impact on the global atmosphere. Our changing climate
affects the composition of phytoplankton species composition and requires the organisms to adapt to this changing
environment, influencing micronutrient bioavailability and
other biogeochemical parameters. Studies to monitor phytoplankton species composition are as important as are molecular and genetic approaches on understanding adaptation
mechanisms of phytoplankton in regard to changing oceanic
conditions. Studies dealing with different approaches on
monitoring changes in phytoplankton, their impact on the
microbial loop and adapting mechanisms are welcome.
4.2 Abstracts of Oral Presentations
4.2.1 Under Surveillance – Monitoring
Phytoplankton and Hunting Their Traces
Laura Käse
1*
, Jana K. Geuer
2*
, Bernd Krock
2
, Katja Metfies
2
,
Boris Koch
2,3
, Alexandra Kraberg
1
1
Biologische Anstalt Helgoland, Alfred-Wegener-Institute
Helmholtz Centre for Polar and Marine Research,
Kurpromenade 201, 27498 Helgoland, Germany
2
Alfred-Wegener-Institute Helmholtz Centre for Polar
and Marine Research, Am Handelshafen 12, 27570
Bremerhaven, Germany
3
Hochschule Bremerhaven, An der Karlstadt 8, 27568
Bremerhaven, Germany
*corresponding authors: laura.kaese@awi.de, jana.
geuer@awi.de
Keywords: Phytoplankton, Microscopy, Marine ligands,
Domoic acid, Next-generation sequencing
Marine primary production is not only crucial for regulating the atmosphere. Phytoplankton is also an important base
for oceanic food webs. Their species composition depends
on seasonal conditions, predators and micronutrient availability. (1) An existing monitoring system, the so called
“Helgoland Roads time-series”, should be improved by
incorporating different monitoring methods to include so far
underreported pico- and nanoplankton. (2) As molecular
tracer the bioactive ligand domoic acid should be quantified
in seawater from the Atlantic Ocean. Phytoplankton samples
were taken two times per week and cells were counted optically via microscopy. The same samples were used for nextgeneration sequencing. For domoic acid quantification,
seawater was filtered via combusted glass fiber filters
(0.7 μm) and subsequently concentrated via solid phase
extraction. Molecular characterisation was done with
Fourier-transform ion cyclotron resonance mass spectrometry. Quantification was performed using high-pressure liquid
chromatography coupled to mass spectrometry. Microscopic
Utermöhl counting resulted in high abundances of different
small-sized flagellates and cryptophytes. Smaller organisms
included in the picoplankton group could not be distinguished further using this method. Bigger organisms like the
diatom Pseudonitzschia sp. are hardly distinguishable on
species level using this method. Therefore, comparison of
these counts and the regular Helgoland Roads counts with
sequencing data is necessary. Additionally the sequencing
data will give lots of information about the different species
of cryptophytes that were not further distinguished via
microscope. In comparison to that a flow cytometer is going
to be used for automated counting and cell sorting. Domoic
acid’s molecular formula could be detected in most samples.
Additionally, it could be quantified in surface water. Higher
concentrations were measured in the northern hemisphere
(up to 172 pmol L
−1
) compared to the southern hemisphere
(up to 15 pmol L
−1
). This method could potentially be transferred to detect and quantify other relevant target ligands.
4.2.2 NMR-Spectroscopic Study of Dissolved
Organic Matter During a Microalgal Spring
Bloom
Christian Zurhelle
1*
, Julian Mönnich
1
, Jan Tebben
2
and
Tilmann Harder
1,2
1
Faculty of Biology and Chemistry, University of Bremen,
Leobener Straße UFT, D-28359 Bremen, Germany
Appendices