Conference Proceedings - IAD

39th IAD Conference, August 2012, Szentendre, Hungary
settlements of Tomaševac, Opovo (Site 5) and Pančevo (Site 6). According to
the standard water quality parameters, measured in the investigated period
(Teodorović et al. 2010), both water and sediment of the Tamiš River mostly
belonged to the I-II class according to the TransNational Monitoring Network
(TNMN) (ICPDR, 2009) criteria, with the general degradation of the water quality
occurred downstream (especially nearby the City of Pančevo). However,
according to the concentrations of nitrites and orthophosphates, the water
column along the studied stretch of Tamiš River was substantially enriched with
nutrients (Teodorović et al. 2010). Moreover, an organic matter load, expressed
as biological oxygen consumption (BOD5), was substantially present and
increased along the hydromorphologically altered watercourse (Teodorović et al.
2010).
The aim of this study was to assess the ecological potential of a heavily modified
water body using the phytoplankton and benthic macroinvertebrates. This was
done by the extensive exploration of the saprobiological quality of the studied
stretch of the Tamiš River during three seasons (summer, autumn and spring).
Furthermore, we aimed to test whether the assessment based on two different
organism groups would be correlated. In addition, this paper addresses the
knowledge gap in linking biological assessment with hydromorphological state of
a heavily modified water body.
Materials and methods
Phytoplankton and benthic macroinvertebrates were sampled at six sites along
117 km of the lower reach of the Tamiš River with the aim to assess the
ecological potential of this heavily modified water body. The sampling was,
therefore, conducted approximately at every 20 km of the river stretch, during
three seasons: summer and autumn 2009, as well as spring 2010. The first
sampling site (Site 1, Fig. 1) was located at the most upstream settlement
nearby Tamiš in Serbia, Jaša Tomić, while the last sampling site (Site 6, Fig. 1)
was located in the vicinity of the mouth of the Tamiš River, nearby the city of
Pančevo.
Phytoplankton was sampled using the plankton net with the mesh size of 25 µm.
Species were identified with the standard taxonomic keys and the saprobic index
was calculated using the individual species saprobic values according to Gulyas
(1998).
Benthic macroinvertebrates were sampled using the Van-Veen type of benthic
sampler, with a sampling area of 225 cm 2 . Samples were sorted immediately
after collection, in the laboratory. Taxa were identified using standard keys to the
lowest taxonomic resolution possible, usually species.
The saprobic index was based on individual saprobic values according to the
www.freshwaterecology.info database for benthic macroinvertebrates of Europe.
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