EGAS41 - Swansea University

41 st EGAS CP 141 Gdańsk 2009
Fluorimetric measurements in vivo of surface seawater around
the Svalbard Islands
V. Drozdowska, W. Walczowski, J. Piskozub, T. Petelski, T. Zieliński
Institute of Oceanology , Polish Academy of Sciences, 81-712 Sopot,
ul. Powstańców Warszawy 55, Poland
The Nordic Seas have been for many years the subject of the research of ocean circulation
conducted by the Institute of Oceanology PAS [1], especially the inflow of Atlantic water
and the intensive turbulent mixing of these waters with Arctic and shelf waters. Ocean
currents affect various biological processes, and affects the supply of organic matter and
oxygen which constitute the base for the unique flora and fauna of Svalbard islands as
well as changes occurring in this area are limiting.
Fluorimetric examinations of surface waters, with the Fluorimeter M32B produced by
LDI Ltd [1], were carried out repeatedly during Arctic cruises on board of r/v Oceania.
Results presented herein come from AREX campaigns 2003 and 2006.
The in vivo fluorescence excitation spectra of phytoplancton species in seawater were
measured at one emission wavelength. The spectral range (excitation 400 to 660 nm,
emission 680 nm) was aimed to reveal fluorescence of chlorophyll a induced via accessory
pigments.
On the basis of the analysis of recorded spectra, it is possible to notice the rise in
the abundance of the phytoplankton and changes of the spatial distribution of the phytoplankton
species characteristic for Atlantic, Arctic and shelf waters. Comparisons of
spatial patterns of the phytoplankton pigments abundance and the physical characteristics
of water masses were conducted.
It is possible to conclude that the observed changes of the abundance and spatial distribution
of the phytoplankton species are controlled by water mass properties being found
in a given year, that is by the inflow of Atlantic waters into the area of Svalbard islands. In
order to establish credible knowledge about the trends of phytoplankton changes a longer
time-series is needed. Therefore the fluorimetric studies are being continued in order to
determine the interannual variability and longer-term changes in the marine ecosystem of
the archipelago [3].
References
[1] W. Walczowski, Diss. and Monogr. of IOPAS vol. 22, pp. 241 (2009)
[2] L. Poryvkina, S. Babichenko, A. Leeben, EARSeL eProceedings No. 1 (2000)
[3] V. Drozdowska, 2007, Oceanologia, 49 (1), pp. 59-69 (2007)
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