A Checklist of Freshwater Zooplankton on the Territory of Kragujevac City (Serbia) and it’s Surrounding Areas

Aleksandar M. Ostojić1, Ivana D. Radojević1, Milica P. Obradović1 and Dušica J. Radoičić1

 

 

 

1 Instutute of Biology and Ecology, Faculty of Science, University of Kragujevac, 34000 Kragujevac, Serbia; e-mail: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

 

 

Abstract

The research of zooplankton fauna in four reservoirs in Kragujevac city and its surrounding areas showed the existance of nearly 200 taxa of 4 groups: Protozoa, Rotifera, Cladocera and Copepoda. These species are generally widespread. The application of Sørensen and Jaccard similarity indices showed the highest similarity between Grošnica and Gruža reservoirs and the lowest between Lake Šumarice and Lake Bubanj. The obtained values are the result of the fact that not all reservoirs were researched with the same intensity, as well as the fact that they vary in size.

Keywords: Freshwater zooplankton, Protozoa, Rotifera, Cladocera, Copepoda, similarity indices, Kragujevac

 

Introduction

 

In Kragujevac city and its surrounding areas, there are four reservoirs different in size, age and type of use (Ostojić et al., 2012). The analyses of faunal composition of zooplankton was conducted in all four of them. However, the research varied in dynamics and scope. Reservoirs Grošnica (Janković, 1966) and Gruža (Karaman and Karaman, 1989; Martinović-Vitanović and Kalafatić, 1990) were researched shortly after their formation, but also a few decades later (Ostojić, 2000a,b). Zooplankton research in other two reservoirs, Lake Bubanj and Lake Šumarice, were considerably smaller in scope (Ostojić, 2004; Ostojić et al., 2012).

The aim of this paper is to summarise all the results of zooplankton analyses in the said reservoirs and to create a checklist which will contribute to a better understanding of the diversity and distribution of zooplankton in Serbia.

 

Description of investigated localities

The Grošnica Reservoir is the oldest water supply reservoir on the territory of Serbia and was formed on the river of the same name. The dam was constructed between 1931 and 1937, and the reservoir was filled in 1938. The system supplied the city with an adequate amount of water up until 1950. However, from that period on, the volume of the lake has undergone significant reduction due to increased consumption and filling with sediments.

During the period of 1960–1962, the dam was raised by 7.3 m. During the warm period of the year, thermal stratification is observed from May to the end of September (Ostojić, 2000b).

Lake Bubanj formed in the alluvial plane of the Lepenica River, in an abandoned clay pit. The lake formation process began in 1955. The lake is supplied with water from a subterranean spring, from the Bubanj Drinking Fountain and by rainfall. The lake is surrounded by a belt of flat unobstructed terrain of approx. 10ha, with scarce woody vegetation. Moreover, the lake is situated in an urban zone not far from the city centre. It is surrounded by busy roads on three sides, and by "Crvena Zastava" service shop on the fourth. The lake once had a discharge trench, which is now obstructed by a municipal sewer and is out of use (Simić et al., 1994).

The Šumarice Lake formed during the period between 1964-1967 when a dam was constructed on the Sušički Potok stream. The reservoir was formed for irrigation and recreational purposes. The reservoir is surrounded by oak wood on one side, while the other side is modifed for recreational uses (Ostojić et al., 2012).

The Gruža Reservoir was formed on the Gruža River. Construction of the dam began in 1979, and the reservoir was filled with water in 1985. The large surface area to volume ratio favours eutrophication. The reservoir is surrounded by farmland, and receives wastewater from neighbouring settlements (Ostojić, 2000a).

 

Characteristics of the reservoirs are given in Table 1.

 

Table 1: Characteristics of the investigated reservoirs

Table01

 

Material and Methods

Qualitative samples of plankton were taken with a plankton net (mesh size 25 μm). Samples were preserved with 4% Formalin at the collection site.

Monthly sampling was carried out during the period from October of 1996 to September of 1998 in the Grošnica and Gruža Reservoirs.

Qualitative samples of zooplankton in Lake Bubanj were taken once a month during the period from November of 1992 to June of 1993. In 1994, samples were taken once a month throughout the summer.

Qualitative analysis sampling of zooplankton in Lake Šumarice was carried out during April, July and September of 2011.

Comparison of the faunistic composition of zooplankton in the said reservoirs was investigated using the Sørenson similarity index (Schwerdtfeger, 1975):

For01

where c is the number of species present in one population, b is the number of species present in the other population, and c is the number of species present in both populations.

The Jaccard index (Cj) was used to measure similarity (Schwerdtfeger, 1975):

For02

where a is the number of species present in one population, b is the number of species present in the other population, and c is the number of species present in both populations.

 

Results and Discussion

The list of taxa recorded in the reservoirs during the investigation is given in Tables 2 and 3. A total number of 188 taxa were recorded, but this list could be expanded by ten more species that were recorded by Janković (1966), and which were not registered in our research (Tab. 2). The greatest number of taxa was registered in Šumarice (114), and the smallest in Bubanj (41) (Tab. 3), as was expected since it is the smallest lake with the smallest scope of research. The research did not include Protozoa.