IMPACT OF WASTE-WATERS FROM MIND LECE ON DIVERSITY OF MACROZOOBENTHOS IN THE GAZDARSKA REKA RIVER, RIGHT-HAND TRIBUTARY OF THE JABLANICA REKA RIVER

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1 IMPACT OF WASTE-WATERS FROM MIND LECE ON DIVERSITY OF MACROZOOBENTHOS IN THE GAZDARSKA REKA RIVER, RIGHT-HAND TRIBUTARY OF THE JABLANICA REKA RIVER 1, Zoran MARKOVI] 2 & Miloje BRAJKOVI] 1 1 Faculty of Biology, 2 Faculty of Agriculture, University of Belgrade, Belgrade, Studenski trg 16, Serbia and Montenegro ivanas@bf.bio.bg.ac.yu I., Markovi} Z. & Brajkovi} M. (2004). Impact of waste-waters from mind Lece on diversity of macrozoobenthos in the Gazdarska Reka River, right-hand tributary of the Jablanica Reka River. Proceedings of the 2 nd Congress of Ecologists of the Republic of Macedonia with International Participation, , Ohrid. Special issues of Macedonian Ecological Society, Vol. 6, Skopje. Investigations of impact of wastewaters from mind Lece on diversity of macrozoobenthos in the Gazdarska reka River (a right-hand tributary of the Jablanica reka River) were conducted during years 2001 and The bottom fauna was composed of 14 groups of macroinvertebrates with 73 determined taxa. The most varied groups were the insect orders Trichoptera (17 taxa), and Diptera (13), Plecoptera (11), Coleoptera (10) and Ephemeroptera (9), while the most uniform were insects belonging to classes Hirudinea, order Odonata and family Ancilidae Larvae belonging to insect orders Ephemeroptera, Plecoptera and Trichoptera were dominant in benthocenosis at first and second localities. These localities were characterized by highest values of diversity index, 3.2 and 3.0 respectively. Due to emptying of wastewater from mind Lece at third locality value of diversity index abruptly dropped to 0.1 due to capacity of the river for self-purification, the variety of bentocenosis increases at localities downstream from locality 3. Key words: Macrozoobenthos, diversity, bioindicator, Gazdarska reka River. Introduction The communal and industrial wastewater that has reached the aquatic ecosystems changes the quality of the recipient and causes the replacement of community of clean waters with community of polluted ones. Being unable to adapt themselves to the negative changes, the more susceptible water organisms disappear, while the more tolerant ones fill the emptied ecological niches, which as a result reduces the diversity in the community of water organisms. Within the biocenoses of small running waters, zoobenthic organisms on account of their bindness to bottom, long life cycle and limited possibility of movement are sensitive indicators of changes in abiotic environmental factors. The Gazdarska reka River is a small hill and mountain running water. Since the Gazdarska reka River along its course flows only through two small settlements, Gazdare and Lece, with no industrial plants in them, antropogenic influence on macrozoobenthos and water quality should be very small. However, there is a mind of lead and zinc Lece near village of Lece, whose waste waters, through a no named stream, flows into the Letska reka River, right-hand tributary of the Gazdarska reka River. Since all other antropogenic influences on this water current are minimal it could be used as a good model system for investigation of influence of mind of lead and zinc on composition of benthocenosis and water quality. Material and methods The Gazdarska reka River, right-hand tributary of the Jablanica reka river (the third order tributary of the Danube), arises at 800 m a.s.l. on mountain Radan. It is formed by confluence of the Gajtanska and Letska reka rivers in the village of Gazdare. In this paper the Letska reka River was chosen as the main contributor. The Letska reka River is formed by confluence of the Drenički brook and no named brook, which flows through mind of lead and zinc Lece in the village of Lece. This no named brook, for the purpose of this paper, is named the Mind brook. Along a 19-km stretch of the river's course, samples of bottom fauna was collected with a net according to 247

2 et al. Tab. 1. Qualitative composition of macrozoobenthose of the Gazdarska reka River. 248 Zbornik na trudovi od 2-ot Kongres na ekolozite na Makedonija

3 Surber from sectors measuring 300 cm 2 in area at 7 localities, from July of 2001 to April of Locality 1 at 680 m a.s.l in village of Donji Gajtan. Bottom is made of rock, with average dept of 0,11 m and width of 2 m. Water temperature varied from C (January 2002) to 17 0 C (July 2001). Locality 2 is 6 km downstream from the spring of the Drenicki brook and 200 m upstream from the confluence with the Mind brook in the village of Lece. Dept of the riverbed was 0,11 m and width 2,5 m. Locality 3 is on the Mind brook, 300m upstream from confluence with the Drenički brook. Average width was 1 m, and dept 0.12 m. Locality 4 is on the Letska reka River, 300-m downstream from confluence of the Drenički brook and the Mind brook in the village of Lece. Bottom is consist of rocks, with average depth of 0.07 m and width of 2.8 m. The lowest water temperature C was recorded in winter of 2002, and the highest C in summer of Locality 5 is at the 14th km of river course of the Letska reke River. Dept of the river was 0,10 m and width 2 m. Locality 6 is on the Gajtanska reka River, in the village of Gazdare, 300 m upstream from confluence of the Gajtanska and Letska reka River. Dept of the river was 0,18 m and width 4 m. Locality 7 is 200m upstream from the source of the Gazdarska reka River in the Jablanica river, and 2- km downstream from the confluence of the Gajtanska and Letska reka Rivers. Average dept was 0,09 m, and width of the riverbed 3,5 m. Water temperature varied from 3 0 C (winter of 2002) to 25 0 C (summer of 2001). The Shannon-Weaver index was used to estimate α- diversity and the Sørensen similarity index to estimate β-diversity Southwood (1978). Family biotic index FBI was calculated according to method of Plafkin-a, Plafkin et al. (1989). The identification of aquatic macroinvertebrates was conducted by using the keys for determination after Hickin (1967); Roskosny (1980); Glöer et al. (1985); Lepneva (1964; 1966). Results and Discussion The bottom fauna of the Gazdarska reka River is composed of 14 groups of macroinvertebrates (Tab. 1) with 73 determined taxa. The greatest diversity showed the insect orders Trichoptera (17 taxa), Diptera (13), Plecoptera (11), Coleoptera (10) and Ephemeroptera (9) while the simplest composition showed the classes Hirudinae (with species Erpobdella testacea and E. octoculata), order Odonata with two identified speciese (Gomphus vulgatissimus and Onychogomphus forcipulata) and families Ancylidae (with species Ancylus fluviatilis). Water wastes from the mine of lead and zinc Lece have a significant impact on qualitative and quantitative composition of macrozoobenthose of the Gazdarska reka River. This is caused by toxic pollution of great intensity from the mine Leca so that in spring in the locality 3 only individuals from the family Chironomidae were observed, while in quantitative samples organisms of macrozoobenthose were not found. Namely, the community of macrozoobenthoses of the first and second localities is characterized by dominance of larvae from the insect orders Ephemeroptera, Plecoptera and Trichoptera (Fig. 1), Fig. 1. Percentage occurrence of macrozoobenthose groups in localities of the Gazdarska reka River. 249

4 et al. Fig. 2. Values of index of diversity and biotic index in the studied localities. high values of index of diversity and low values of biotic index (Fig. 2) which are characteristics of benthocoenoeses of mountaineous rivers/ running waters with poor antropogenic impact. The influx of water wastes from the mine 200 m downstream of the locality 2, brings about the great change in the structure of benthocommunity of the Gazdarska reka River. Thus, the locality 4, which is 400 m downstream of the locality 2, is characterized by the dominance of the species from the genus Simullium (which are also dominant in the localities 5, 6 and 7) and individuals of Oligochaeta and Chironomidae (Fig. 1), whereas larvae of Ephemeroptera are absent. Plecoptera and Trichoptera are present in small numbers (1% and 3,14%, respectively). Index of diversity has low values while biotic index has high values, which are typical characteristics of benthocoenoses of polluted waters. Since the number of Hirudinea, which are indicators of fecal pollution Hilsenhoff (1988), Plafkin et al. (1989); Bode et al. (1996), does not rise in the fourth locality in comparison to the loality 2, it may be assumed that the change in the composition of the community of zoobenthose in the locality 4, is for the most part the consequence of the influx of water wastes from the mine Lece. The values of the index of similarities also point to the intensity of these changes (Tab. 2), which are considerably greater between localities 1 and 2 (0,46) than between localities 2 and 3 (0,33). Thanks to autopurification abilities of the river, in the fifth locality diversity of the bottom fauna increases, biotic index falls, and in addition to the individuals of Simulidae, larvae of Trichoptera also dominate, while Oligochaeta and Plecoptera are absent (Fig. 1). But, the fifth locality is also characterized by the most peculiar composition of benthocoenose because it has the highest index of similarity with the locality 4 (0,41), while its index of similarity is considerably lower with other localities varying from 0,12 with the locality 2 to 0,3 with the locality 6 (Tab. 2). This can be a consequence of adaptation of macrozoobenthose community to toxic pollution from the mine Leca. The seventh locality shows small similarity with the fifth locality (Tab. 2). It is also characterized by remarkable dominance of individuals of Sumulidae (Fig. 1) but also considerable occurrence of larvae of Plecoptera and Ephemeroptera, which are absent or are scarce in lacality 5. These changes are probably caused Tab. 2. Index of similarity of macrozoobenthos community in the studied localities. 250 Zbornik na trudovi od 2-ot Kongres na ekolozite na Makedonija

5 by the influx of water of the Gajtanska reka River in the village Gazdare, because there is a great value of index of similarity between 7 and 6 locality, which is on the Gajtanska reka River, 300 m upstream of confluence of the Gajtanska and Letske reka Rivers. In addition, the sixth locality, apart from the dominance of Simulidae and Chironomidae is characterized by considerable occurrence of the larvae of Ephemeroptera and Plecoptera (Fig. 1). Summary The bottom fauna was composed of 14 groups of macroinvertebrates with 73 determined taxa. The most varied groups were the insect orders Trichoptera (17 taxa), and Diptera (13), Plecoptera (11), Coleoptera (10) and Ephemeroptera (9), while the most uniform were insects belonging to classes Hirudinea, order Odonata and family Ancilidae Larvae belonging to insect orders Ephemeroptera, Plecoptera and Trichoptera were dominant in benthocenosis at first and second localities. These localities were characterized by highest values of diversity index, 3.2 and 3.0 respectively. Due to emptying of wastewater from mind Lece at third locality value of diversity index abruptly dropped to 0.1 due to capacity of the river for self-purification, the variety of bentocenosis increases at localities downstream from locality 3. References Bode, R.W., Novak, M.A., and Abele, L.E. (1996). Quality Assurance Work Plan for Biological Stream Monitoring in New York State. NYS Department of Environmental Conservation, Albany, NY. 89 pp. Glöer, P., Meler-Brook, C. und OstermanN, O. (1985). Süsswassermollusken. Ein Bestimmugsschlüssel für die Bundesrepublik Deutschland Hamburg, Hickin, E. N. (1967). Caddis larvae. Larvae of the British Trichoptera. Hutchinson, London, 457 pp. Hilsenhoff, W.L. (1988). Rapid field assessment of organic pollution with a family-level biotic index. J. N. Am. Benthol. Soc. 7(1): Lepneva, S.G. (1964). Ryceinki-Trichoptera. Tom II. Vyp.1. Fauna SSSR. Nauka, Moskva-Leningrad, 558 pp. Lepneva, S.G. (1966). Ryceinki Trichoptera. Tom II. Vyp.6. Fauna SSSR. Nauka, Moskva-Leningrad, 560 pp. Plafkin, J.L., Barbour, M.T., Porter, K.D., Gross, S.K., and Hughes, R.M. (1989). Rapid Bioassessment Protocols for use in Streams and Rivers: Benthic Macroinvertebrates and Fish. U.S. Environmental Protection Agency. EPA 440/4-89/ chapters, Appendices A-D. Rozkosny, R. (1980). Klic larev vodniho hmyzu. Ceskoslovenska Akademie Ved, Praha, 521 pp. SouthwooD, T. R. E. (1978). Ecological Methods. Champan and Hall, London. 251