Hidrológiai Közlöny, 2014 (94. évfolyam)
2014 / 5-6. különszám - LV. Hidrobiológus Napok előadásai
58 HIDROLÓGIAI KÖZLÖNY 2014. 94. ÉVF. 5-6. SZ. Heterogeneity of lake velencei based on CLADOCERA remains and sediment chemistry Csilla Lakatos'*, IstvánGyulai2, Rajmund Kovács', Csaba Berta2, Zsuzsanna Balogh', János Korponai3, Edina Simon' 'Department of Ecology, Institute of Biology and Ecology, Faculty of Natural Science, University of Debrecen, Egyetem tér 1, H-4032. Debrecen, Hungary department of Hydrobiology, Institute of Biology and Ecology, Faculty of Natural Science, University of Debrecen, Egyetem tér 1, H-4032. Debrecen, Hungary department of Chemistry and Environmental Science, Institute of Geography and Environmental Sciences, Faculty of Natural Sciences, University of West Hungary, Károlyi Gáspár tér 4, 9700. Szombathely, Hungary * csiraf@gmaiI.com Abstract: The characteristic of Lake Velencei is the closed up effect by reeds. The heterogeneity of the lake disappeared because of anthropogenic activities. Based on the results of water chemistry the lake was shared on three parts: black, grey and green water, where nature reserve area is the black water, the middle of the lake is the grey water and the East side of the lake is the green water. Our aim was to assess that this fragmentation based on the occurrence of Cladocera taxon and sediment chemistry (organic matter and calcium-carbonate content). Surface soft sediment samples collected from 9 sampling sites: nature reserve a- rea (Kerek-tisztás, Német-tisztás, tunnel Dinnyés-kajtori), middle of the lake (Lángi-tisztás, Vendel-tisztás, Agárdi Hosszútisztás, Gárdonyi Nagy-tisztás), and east part of the lake (Öreg-tisztás, Fürdető). The average number of individuals were 6,435 and 25 taxon were identified in 1 cm3 sediment samples. Our results shows the maximum average number of individuals and maximum number of species were found at the nature reserve area, and individuals were accumulated in the tunnel Dinnyés-kajtori. Using Cluster analysis the fragmentation of Cladocera taxon and sediment chemistry were different than water chemistry. The nature reserve areas (Kerek-tisztás, Német-tisztás) were also separate areas from others based on the Cladocera and water chemistry assays too. In our results showed that the middle of the lake and the East part of the lake (Agárdi Hosszú-tisztás, Gárdonyi Nagy-tisztás, Öreg-tisztás és Fürdető) are similar to each other according to Cladocera taxon and sediment chemistry. Our study demonstrated that the „transition area is a seprated area between the nature reserve area and the recreation area,” (Lángi-tisztás, Vendel-tisztás) which was different from others based on Cladocera and sediment chemistry. Keyword: organic matter, calcium-carbonate, surface sediment, Cladocera.
