Hidrológiai Közlöny, 2014 (94. évfolyam)

2014 / 5-6. különszám - LV. Hidrobiológus Napok előadásai

92

HIDROLÓGIAI KÖZLÖNY 2014. 94. ÉVF. 5-6. SZ.

Epi- and metalimnetic profile of phytoplankton in a stratifying shallow oxbow between 2007 and 2009 (MalomTisza, Hungary)

E. T-Krasznai, A. Abonyi, J. Görgényi, P. Török

Abstract: The vertical distribution of phytoplankton was analysed focusing on the epi- and metalimnetic zone in the Malom-Tisza oxbow, Hungary. Altogether 266 taxa were identified (6 anaerob bacteria, 35 Cyanobacteria and 225 eukaryotic algae). Besides the dominance of self-shade adapted cyanobacteria, some rare species was also detected during the study period (Gonyostom- um semen, Aphanocapsaparasitica, Cystodinium cornifax). While the spring phytoplankton assemblages seemed to be similar between the three years, late summer climax compositions were different. Change in strength of thermal stratification can play a key role in determining the seasonal succession of phytoplankton. In 2008, a relatively mild spring generated weaker thermal stratification through the whole year, might being responsible for the occurrence of new taxa, like Gonyostomum semen in the Malom-Tisza oxbow.

Keywords: shallow lake, functionally deep lake, thermal stratification, water quality, phytoplankton diversity.

2007

2008

2009

MAJ JUN JUL AUG SZEPMAJ JUN JUL AUG MAJ JUN JUL AUG SZEP

1. ábra. A Malom-Tisza holtágfitoplankton biomasszájának vertikális eloszlása 2007 és 2009

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1

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2007 2008 2009

MAJ JUN JUL AUG SZEPMAJ JUN JUL AUG MAJ JUN JUL AUG SZEP

3.5 3

2.5 2

1.5 1

0.5

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t5

c

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c

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2. ábra. A Malom-Tisza holtág fitoplankton Shannon diverzitásának vertikális eloszlása 2007 és 2009 között