Original scientific paper
https://doi.org/10.1515/cjf-2017-0013
ZOOPLANKTON IN ANCIENT AND OLIGOTROPHIC LAKE OHRID (EUROPE) IN ASSOCIATION WITH ENVIRONMENTAL VARIABLES
Orhideja Tasevska
Maria Špoljar
orcid.org/0000-0003-1006-8300
Dafina Gušeska
Goce Kostoski
Suzana Patcheva
Elizabeta Veljanoska Sarafiloska
Abstract
Zooplankton is studied in the ancient, tectonic, oligomictic and
oligotrophic Lake Ohrid (Macedonia, South Eastern Europe). The main
aim of this study was to assess the seasonal and spatial patterns of the
zooplankton functional feeding guilds in relation to the environmental
conditions. Metalimnion of the lake was detected as the most productive
environment, where biomass of the phytoplankton and abundance of
the zooplankton reached their maxima. Pelagial zooplankton of low
abundance (25 ± 22 ind. L-1) consisted of 16 species including two endemic
copepods, Arctodiaptomus steindachneri (Richard, 1897) and Cyclops
ochridanus (Kiefer, 1932). Copepods obtained remarkable share (60%)
in the zooplankton assemblage. Microphagous zooplankton was mainly
comprised of the most abundant rotifer Kellicottia longispina (Kellicott,
1879) in summer, and copepod nauplii during the spring Eudiaptomus
gracilis (Sars, 1862) and C.ochridanus, and autumn C.ochridanus. Due to
their requirements for the bacterio-detritus suspension, this microphagous
zooplankton occupied aphotic hypolimnion during the entire study period.
Raptorials were typically represented by copepodites and adult copepods
in the metalimnion, and were significantly and positively affected by
temperature (r = 0.417, p = 0.001), dissolved oxygen (r = 0.463, p = 0.0001)
and, particularly, phytoplankton biomass (r = 0.708, p < 0.00001). This is
the first study in which the link between the lower and higher trophic levels
is investigated in Lake Ohrid.
Keywords
Copepods; Rotifers; Microphgous; Raptorials; Metalimnion Oligomictic lake
Hrčak ID:
186840
URI
Publication date:
28.9.2017.
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