Transcript riina_klais

Riina Klais
PhD student (2008-2012)
Tartu University (Estonia)
Institute of Ecology and Earth Sciences
Department of Nature and Technology
Supervisor: Kalle Olli
Baltic Sea phytoplankton in a temporal shift
Data:
Since 1965, there have been ca 15 000 phytoplankton samples collected and
analyzed during national monitoring programs.
After extremely time consuming work over 40 years, and recent collection and
harmonization of those varying data tables from different providers, we
have 15 000 samples, with approximately 500 000 single records in a single
table for comprehensive analysis of the trends and patterns in species
composition in the Baltic Sea.
Data providers:
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Finnish Environment Institute (SYKE), Finland
Finnish Institute of Marine Research (FIMR), Finland
Helsinki city, Finland
Institute of Aquatic Sciences, Latvia
Stockholm University, Sweden
Institut für Ostseeforschung Warnemünde (IOW), Germany
National Environmental Research Institute (NERI), Denmark
Estonian Marine Institute, Estonia
HELCOM
Data
Not homogenous spatially
Not homogenous in time
Synthesis
Exercise no 1:
Diatom / dinoflagellate rivalry in spring blooms.
It has been suggested, that dinoflagellates are taking over spring blooms, and
competing out the diatoms;
Possible reasons: climate change – i.e. positive NAO indexes, resulting in
milder winters, and early stratification in spring – giving the advantage to
motile species (Wasmund and Uhlig, 2003); anthropogenic – i.e. decreasing
concentration of silicate (Danielsson et al, 2008)?
Synthesis
Problem 1: defining the spring samples
biomass of the sample, timing (varies with latitude),
proportion of diatoms/dinoflagellates, indicator species…
Variable analysed:
ProportionDinophyceae = biomassDinophyceae /(biomassBacillariophyceae +
biomassDinophyceae)
Gulf of Finland
Bothnian bay and Bothnian Sea
Northern Baltic Proper + Archipelago sea,
Gotland Basin + Gulf of Riga
Southern Baltic Proper, the Sound
Questions
a)
Is the rivalry between dinoflagellates and diatoms somehow affected by
the climate change (NAO, ice cover etc) or chemical properties of Baltic
Sea (decreasing silica content)?
b)
Is it general ‘dinos’ vs ‘diatoms’ trend, or, is it only one group (suspect is
Woloszynskia/Scrippsiella family), that is colonizing in its own specific way
new locales (without particular help from climate or human impact)?
c)
What do we loose/win, if we have dinoflagellates instead of diatoms in
spring blooms?
Synthesis
Exercise no 2:
Late summer species
composition.
Preliminary results
indicate, that most
important factor in PC
analysis is always time
About me
Scientific interests:
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numerical ecology, statistical methods for analyzing ecological data
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phytoplankton ecology, drivers for changes in species composition and
biodiversity in Baltic Sea
BSc: (2005) “Heterotrophic nanoflagellates in microbial food web”
References
1.
Å. Danielsson, L. Papush, L. Rahm, 2008. Alterations in nutrient limitations — Scenarios
of a changing Baltic Sea. Journal of Marine Systems, 73: 263-283.
2.
Wasmund, N., Uhlig,S., 2003. Phytoplankton trends in the Baltic Sea. ICES Journal of
Marine Science, 60: 177-186.
you!
Thank