Riina KlaisPhD student (2008-2012)

Tartu University (Estonia)Institute of Ecology and Earth SciencesDepartment of Nature and Technology

Supervisor: Kalle Olli

Baltic Sea phytoplankton in a temporal shiftData:

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: Finnish Environment Institute (SYKE), FinlandFinnish Environment Institute (SYKE), Finland Finnish Institute of Marine Research (FIMR), FinlandFinnish Institute of Marine Research (FIMR), Finland Helsinki city, FinlandHelsinki city, Finland Institute of Aquatic Sciences, LatviaInstitute of Aquatic Sciences, Latvia Stockholm University, SwedenStockholm University, Sweden Institut für Ostseeforschung Warnemünde (IOW), GermanyInstitut für Ostseeforschung Warnemünde (IOW), Germany National Environmental Research InstituteNational Environmental Research Institute (NERI), Denmark(NERI), Denmark Estonian Marine Institute, EstoniaEstonian Marine Institute, Estonia HELCOMHELCOM

DataNot homogenous spatially

Not homogenous in time

SynthesisExercise 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)?

SynthesisProblem 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

Questionsa) 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?

SynthesisExercise no 2:

Late summer species composition.

Preliminary results indicate, that most important factor in PC analysis is always time

About meScientific interests:

• numerical ecology, statistical methods for analyzing ecological data

• phytoplankton ecology, drivers for changes in species composition and biodiversity in Baltic Sea

BSc: (2005) “Heterotrophic nanoflagellates in microbial food web”

References1. 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.

Thank you!