Species Composition and Seasonal Variations of the Gastropoda in

Acta hydrochim. hydrobiol. 32 (2004) 6, 393−400

Yes¸im C ¸ abuka, Naime Arslana, Veysel Yılmazb a

Osmangazi University, Fen-Edebiyat Fak., Biyoloji Bölümü, 26480 Mes¸elik, Eskis¸ehir, Turkey b Osmangazi University, Fen-Edebiyat Fak., ˙Istatistik Bölümü, 26480 Mes¸elik, Eskis¸ehir, Turkey

393

Species Composition and Seasonal Variations of the Gastropoda in Upper Sakarya River System (Turkey) in Relation to Water Quality* Species composition, abundance, and seasonal distribution of the Gastropoda fauna and the physical and chemical variables of Upper Sakarya River System have been investigated between October 1998 and August 1999. Gastropod fauna in the Upper Sakarya River System was represented by 9 species of Prosobranchia and 7 species of Pulmonata. Diversity, dominance, and abundance of the Gastropoda species were recorded seasonally. The abundance of some of the 16 species was correlated positively with temperature, dissolved oxygen and negatively or positively with pH and nitrate. It was observed that Gyraulus albus (Müller, 1774), Physa acuta Draparnaud, 1805, Valvata pulchella Studer, 1820, and Oxyloma elegans (Risso, 1826) can tolerate a high level of NO3⫺-N while V. piscinalis (Müller, 1774) spread out in unpolluted water. Although the species and their numbers change at the stations, the maximum numbers were found during autumn, while minimums were identified during the winter sampling. Gyraulus albus was the most widespread species in our research area. Only 5 species (Gyraulus albus, Physa acuta, Valvata cristata (Muller, 1774), Valvata pulchella, Melanopsis praemorsa costata (Olivier, 1804)) were determined each season. However, no Gastropoda were found at the station 3 that has high BOD, NO3⫺-N, NO2⫺-N, and NH3 levels.

Artenzusammensetzung und saisonale Variation der Gastropoden im oberen Teil des Sakarya River Systems (Türkei) in Beziehung zur Wasserbeschaffenheit

* This study was part of an MSc thesis and supported by the Research Foundation of Osmangazi University, Eskisehir, project number: 1998-17.

Artenzusammensetzung, Abundanz und saisonale Verbreitung der Gastropodenfauna sowie physikalisch-chemische Parameter der Wasserbeschaffenheit im System des Oberen Sakarya River wurden zwischen Oktober 1998 und August 1999 untersucht. Die Gastropodenfauna wurde durch 9 Prosobranchier und 7 Pulmonaten repräsentiert. Diversität, Dominanz und Abundanz der Gastropodenfauna wurden bestimmt. Die Abundanz einiger der 16 Arten war positiv korreliert mit der Wassertemperatur und der Sauerstoffkonzentration, negativ oder positiv korreliert mit dem pH-Wert und der Nitratkonzentration. Gyraulus albus (Müller, 1774), Physa acuta Draparnaud, 1805, Valvata pulchella Studer, 1820 und Oxyloma elegans (Risso, 1826) tolerieren erhöhte Nitratkonzentrationen, während V. piscinalis (Müller, 1774) sich in unbelastetem Wasser ausbreitet. Obwohl Arten- und Individuenzahlen an den Probenahmestellen wechseln, traten generell die Maxima im Herbst, die Minima im Winter auf. Gyraulus albus war die am weitesten verbreitete Art im Untersuchungsgebiet. Nur 5 Arten (Gyraulus albus, Physa acuta, Valvata cristata (Muller, 1774), Valvata pulchella, Melanopsis praemorsa costata (Olivier, 1804)) wurden zu jeder Jahreszeit beobachtet. Keine Gastropoden wurden an der Probenahmestelle 3 mit ihren hohen Konzentrationen von BSB, NO3⫺-N, NO2⫺-N und NH3 beobachtet. Keywords: Pollution, Nitrate, Nitrite, Ammonium, Oxygen, pH, Turkey Schlagwörter: Verunreinigung, Nitrat, Nitrit, Ammonium, Sauerstoff, pH-Wert, Türkei

Correspondence: Y. C ¸ abuk, E-mail: [email protected]

DOI 10.1002/aheh.200300544

 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

394 Y. C ¸ abuk et al.

Acta hydrochim. hydrobiol. 32 (2004) 6, 393−400 Fig. 1: Sampling stations and sources of pollutant affecting the Upper Sakarya River System. Roman numbers are indicated sources of pollutant: I Organised industrial district; II Eskis¸ehir municipal slaughter house; III Sugar beet factory; IV Textile factory; V Kütahya magnesite factory; VI Kütahya nitrogen factory; VII Sugar beet factory; VIII Kütahya municipal slaughter house. Probenahmestellen und Belastungsquellen im System des Oberen Sakarya River. Römische Ziffern kennzeichnen die Belastungsquellen: I organisierter industrieller Bezirk; II Städtischer Schlachthof von Eskis¸ehir; III Zuckerfabrik; IV Textilfabrik; V Magnesitfabrik von Kütahya; VI Stickstofffabrik von Kütahya; VII Zuckerfabrik; VIII Städtischer Schlachthof von Kütahya.

1 Introduction

3 Methods

Benthic macroinvertebrates are of importance to aquatic biologist because they can indicate pollutional effects on the environment [1]. Mollusca occupy a prominent place among aquatic organisms suitable for biological monitoring [2, 3] and they are used often for passive and active biomonitoring and in hazard and risk assessment [4]. Even though, Girgin, [5], Kazancı and Girgin [6], Sözen and Yig˘it [7], Egemen et al. [8], Kazancı and Dügel [9] have studied the ecology of different groups of invertebrates, little information is available about the ecology of aquatic gastropods in inland water bodies of Turkey.

3.1 Gastropoda samples

2 Study area Sakarya River (824 km) is one of the longest rivers in Turkey. It rises from 5 different springs in the western Anatolian Plateau, as called Sakarbas¸ı. The study area, Upper Sakarya River System (Fig. 1), is consisting of Porsuk stream, one of the biggest tributaries, Sakarya, Seydi and Bardakçı streams and their tributaries. All the streams are being used presently for irrigation and industrial water supply. After the rise of pollution, fishery lost its importance. The most important pollution sources in the basin are domestic wastewaters in Kütahya and Eskis¸ehir [10]. Further sources of pollutants affecting the Upper Sakarya River System are shown in Figure 1.


Samples were collected in duplicates or triplicates per site (by checking all type of substrates) seasonally from October 1998 to August 1999 from 18 stations. Gastropoda samples were caught by net from surface layers of the sediment and brushed from the plant and the stone surface. Two or three random hauls of bottom sediment were taken from each sampling site with a grab sampler, which covered a surface area of 900 cm2 and penetrated to a depth of 5 cm. Samples were fixed with 4 % formaldehyde solution. In the laboratory they were identified and counted under a 10x magnification binocular microscope. Gastropoda were identified to species level using taxonomic keys [11⫺17]. Dominance was used for the numerical analysis. Gastropoda population densities in the research area are examined by means of MANOVA followed by factor analyses and Scheffe’s test [18⫺20]. Correlations between environmental parameters and the abundance of Gastropoda were determined by Pearson’s correlation coefficients.

3.2 Physical and chemical factors Water samples for chemical analysis were collected from each station, at each season, using prewashed polyethylene


Gastropoda in Upper Sakarya River System (Turkey) 395

Table 1: The highest and lowest seasonal values of the measured physico-chemical parameters and the classes of the water quality in the stations (Roman numbers are indicating the classes of the water quality). Abbreviations: St.: station, Temp.: temperature; β-m: beta mesosaprobic; α-m: alpha mesosaprobic; α-p: alpha polysaprobic. Saisonale Maxima und Minima der gemessenen physikalisch-chemischen Parameter und Klassen der Wasserbeschaffenheit (römische Ziffern zeigen die Klasse der Wasserbeschaffenheit). Abkürzungen: St: Probenahmestelle; Temp.: Wassertemperatur; β-m: beta-mesosaprob; α-m alpha-mesosaprob; α-p: alpha-polysaprob. St.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

pH

Temp. °C

DO mg L⫺1

BOD mg L⫺1

NO3⫺-N mg L⫺1

NO2⫺-N mg L⫺1

NH3 mg L⫺1

Water saprobity zone

(8.2...8.5) I (7.5...7.6) I (7.3...7.7) I (7.9...8.1) I (7.4...7.8) I (7.7...8) II (7.7...8.2) II (7.8...8.3) II (8.3...9.4) IV (7.6...8.2) II (7.8...8.1) II (7.4...7.4) I (6.9...7.2)

(5.9...13.6) I (8.5....16.5) I (9.1...16.7) I (8.3...16.8) I (11.9...19) I (9.2...19.4) I (6.8...16.9) I (7.9...16.6) I (7...25.6) II (6.8...18.8) I (5.7...18.5) I (5.1...14.3) I (19.2...20.8) I (4...15.9)

(8.7...13.3) I (2.9...6.9) IV...II (1...7.5) IV...II (5.5...9.1) III...I (0.5...8.9) IV...I (6.2...8.2) II...I (6.7...11.7) II...I (6.3...11.2) II...I (8.5...10.7) I (5.4...8.9) III...I (6.1...8.4) II...I (6...9.2) II...I (2.7...3.6) IV...III (3.1...8.2) III...I (5.8...8.4) III...I (5.5...7.6) III...II (7...10) I (8.1...9.5) I

(1.3...3) I (2...18) I...III (3.7...34.3) I...IV (1.6...4) I (5...11) II...III (1.4...2.8) I (1...3) I (1.1...3.7) I (1...2.6) I (0.8...1.5) I (0.6...2) I (1...3) I (1.2...3.2) I (0.2...3) I (1.2...6.2) I...II (3...9.4) I...III (2.8...5)

(5.9...8.1) II (3.2...11.1) I...III (4.3...8.4) I...II (5.2...9.5) II (7.8...18.8) II...III (4.8...9.3) I...II (4.3...8.8) I...II (5.2...9.8) II (0...0.7) I (0...5.1) I...II (2.01...5.4) I...II (0.06...9.9) I...II (6.6...9.7) II (1.9...7.5) I...II (7.3...12.2) II...III (10.8...15.8) III (3.1...7.7) I...II (3.02...7.2) I...II

(0.06...0.1) IV (0.3...3.1) IV (0.1...1.08) IV (0.02...0.3) III...IV (0.1...0.5) IV (0...0.29) IV (0.03...0.05) III (0.03...0.05) III (0...0.03) III (0...0.07) IV (0...0.01) II (0.02...0.04) III (0) I (0.02...0.07) III...IV (0.02...0.07) III...IV (0.1...0.1) IV (0.02...0.2) III...IV (0.03...0.2) III...IV

(0.08...0.5) III...IV (1.3...4.1) III...IV (1.1...7.7) III...IV (0.2...0.9) II (0.8...3.3) II...IV (0.2...0.8) I...II (0.2...0.4) II (0.2...0.4) I...II (0.1...0.3) I...II (0.1...0.6) I...II (0.2...0.4) I...II (0.03...0.2) I...II (0.08...0.2) I...II (0.02...0.2) I...II (0.1...0.9) I...II (0.2...7.3) II...IV (0.03...1.2) II...III (0.3...1.4) II...III

β-m

(7.5...8.03) II (7.9...8) II (7.2...7.5) I (8...8.1) II (8.2...8.3) II

(8.4...20.1 I (8.4...12.9) I (5.7...13) I (5.5...13.1) I

(3...5.5) I...II

bottles. All samples were analyzed within 24 hours after collection. Water temperature, pH, dissolved oxygen (DO), and salinity were measured in the field with a water quality

α-m α-p oligo/β-m β/α-m β-m β-m β-m β-m oligo/β-m oligo/β-m β-m β-m oligo/β-m β/α-m β/α-m β-m α-m

checker (TOA WQC 22A) from 30 cm depth. The level of NO3⫺-N, NO2⫺-N, NH3, and biochemical oxygen demand (BOD) were determined in the laboratory according to stand-



396 Y. C ¸ abuk et al.

Table 2: Species that dominate the Gastropoda community in the Upper Sakarya River System (numbers in parentheses indicate the relative abundance of dominant species in percent). Dominante Arten der Gastropodengemeinschaft im System des Oberen Sakarya River (Ziffern in Klammern zeigen die relative Abundanz der Art in Prozent). St.

Autumn

Winter

Spring

Summer

1

Gyraulus albus (47)

Pseudoamincola natolica natolica (60)

Gyraulus albus (78.6)


2

Physa acuta (100)

⫺

⫺

Physa acuta (49.7)

3

⫺

⫺

⫺

⫺

4

Gyraulus albus (100)

⫺

Fagotia sangarica (100)

Physa acuta (100)

5

Physa acuta (78.3)

Physa acuta (72.3)

Physa acuta (79)

Physa acuta (70.4)

6

Pseudoamincola natolica natolica (90.9)

Theodoxus heldreichi (100)

⫺


7


Valvata cristata (35)



8

⫺

Gyraulus ehrenbergi (50)

Gyraulus ehrenbergi (38.4)

Valvata cristata (79.4)

9


Valvata pulchella (92.8)



10

⫺

⫺

Radix peregra (50) Sadleriana bhyzanthina (50)

Radix peregra (66.4)

11

Radix peregra (100)

⫺

Theodoxus heldreichi (100)

Radix peregra (100)

12


Fagotia sangarica (76.8)



13

Pseudoamincola natolica natolica (88.7)

Melanopsis praemorsa costata (91.4)

Melanopsis praemorsa costata (100)

Melanopsis praemorsa costata (91.3)

14

Gyraulus albus (80)

⫺

Gyraulus albus (33.2) Gyraulus ehrenbergi (33.2)


15

Gyraulus ehrenbergi (100)




16



⫺

Oxyloma elegans (66.6)

17

⫺

Galbatrunculata (100)

⫺

⫺

18

⫺

Gyraulus albus (50) Valvata cristata (50)

Gyraulus albus (100)


ard methods [21]. Classification of physico-chemical parameters was performed according to the criteria of inland water quality that is commonly used in Turkey [21]. The highest and lowest seasonal values of the measured physico-chemical parameters and the classes of the water quality of eighteen sampling sites of Upper Sakarya River System during the study period are given in Table 1.

4 Results and discussion In the present investigation, 16 species of Gastropoda were identified, nine species belonging to Prosobranchia and


seven species to Pulmonata. The dominant species of the Gastropoda community in the Upper Sakarya River System are shown in Table 2. Seasonal densities of total Gastropoda in the eighteen sampling sites showed considerable fluctuations during the study period ranging from 0 to 54 973 ind. m⫺2 (Fig. 2). In addition, the mean densities of Gastropoda at eighteen sampling sites were significantly different from each other (p < 0.05). The highest mean densities of Gastropoda were observed at stations 5 and 13, 24 990 ind. m⫺2 and 16 981 ind. m⫺2 respectively (Table 3), whereas no Gastropods were observed at



Fig. 2: Seasonal variations in the density of Gastropoda in Upper Sakarya River during the study period. Saisonale Variation in der Dichte der Gastropoden im Oberen Sakarya River während der Untersuchungsperiode.

station 3 that showed high BOD, NO3⫺-N, NO2⫺-N, and maximum NH3 levels (Table 1).

organic load, oxygen and nitrogen compounds in the course of self-purification.

Factor analysis has been applied in order to get factors unrelated with each other. In the result of the analysis, two components were determined and they explained 73.44 % of variances. First component was including BOD, DO, NH3, NO2⫺, NO3⫺, and pH; second component included temperature only. Therefore, partial correlation coefficients were computed among BOD, DO, NH3, NO2⫺, NO3⫺, pH without the influence of temperature. The results given in Table 4 demonstrate the excepted relations within the metabolism of

Correlations of Gastropoda species with physico-chemical parameters of water in the study area are presented in Table 5. The species of Gastropoda were not equally responding to the physico-chemical parameters of the water. The most abundant species in the sampling area through out the study period were Gyraulus albus, Physa acuta, and Valvata cristata. In addition, Gyraulus albus, was the only Gastropod species whose abundance not decreased under high level of NH3.

Table 3: Mean density of individuals (in m⫺2) of Gastropoda samples in the Upper Sakarya River. Mittlere Individuendichte (in m⫺2) der Gastropoden im Oberen Sakarya River. Sta- Mean density Prosobranchia tion of total Gastropoda (in m⫺2)

Pulmonata Fagotia Melanopsis Oxyloma Pseudoamincola Sadleriana Theodoxus Valvata Valvata Valvata Bithynia Galba Gyraulus Gyraulus Physa- Planorbis Radix sangarica praemorsa elegans natolica byzanthina heldreichi cristata piscinalis pulchella badiella truncatula albus ehrenbergi acuta carinatus peregra costata natolica

1

922

0

0

63

28

0

0

0

0

28

0

0

732

15

28

0

28

2

74

0

0

0

14

0

0

0

0

0

0

0

0

14

46

0

0

3

No Gastropoda found

4

84

14

0

0

0

0

0

0

0

0

0

0

14

0

56

0

0

5

24 990

0

0

0

0

0

0

278

0

5 439

0

83

222

84

18 703

181

0

6

1 014

111

0

0

833

0

14

0

0

0

0

0

56

0

0

0

0

7

1 879

0

0

28

0

0

0

211

70

60

0

0

1 260

241

0

0

9

8

1 417

0

0

28

116

0

0

861

0

9

28

0

181

194

0

0

0 28

9

949

0

0

9

0

0

0

111

0

356

0

0

445

0

0

0

10

98

0

0

0

0

28

0

0

0

0

0

14

0

0

0

0

56

11

56

0

0

0

0

0

28

0

0

0

0

0

0

0

0

0

28

12

5 432

278

0

28

0

0

0

2 292

0

181

0

0

1 861

0

778

0

14

13

16 981

959

3 625

0

0

146

0

0

0

21

0

14

0

14

0

0

14

1 417

0

0

0

0

0

42

181

0

305

0

0

667

222

0

0

0

15

445

431

0

0

0

0

0

0

0

0

0

0

0

14

0

0

0

16

1 390

0

0

389

0

0

0

195

0

0

0

139

472

167

28

0

0

12 202

17

56

0

0

0

0

0

0

0

0

0

0

56

0

0

0

0

0

18

139

0

0

0

0

0

0

83

0

0

0

0

56

0

0

0

0



398 Y. C ¸ abuk et al. Table 4: Controlling for temperature partial correlation coefficients among BOD, DO, NH3, NO2⫺, NO3⫺, pH.

and Theodoxus heldreichi showed significant positive correlations to the water temperature (Table 5).

Partielle Korrelationskoeffizienten unter Ausschluss der Wassertemperatur zwischen BSB, Sauerstoffkonzentration, NH3, NO2⫺, NO3⫺, pH-Wert.

Variations of pH are in between 6.9 and 8.3 (except station 9) (Table 1). Because of non-occurrence of extreme variations, temperature and pH have not been considered as restrictive factors for the Gastropoda community. However, the abundance of Theodoxus heldreichi showed a significant negative correlation to the pH of the water. At station 9, minimum pH is 8.3, maximum pH 9.4 (summer sampling). Two species that were determined at station 9 in summer sampling, Radix peregra (Müller, 1774) and Valvata pulchella, are the only species found at the highest pH value in the study area. However, it is known that a low pH value is lethal for many aquatic Gastropoda [23, 24]. The lowest pH value was measured in the field as 6.9 (at station 13 in spring samples) and this was not a limiting level for Upper Sakarya’ Gastropods.

DO

NH3

NO2⫺

NO3⫺

pH

BOD ⴚ0.5743* 0.9543** 0.6735** 0.2703 ⫺0.3799 DO ⴚ0.5794* ⫺0.3993 ⫺0.3167 0.8254** 0.7008** 0.4158 ⫺0.4474 NH3 0.1182 ⫺0.2882 NO2⫺ ⴚ0.5296* NO3⫺ ** P < 0.01; * p < 0.05.

Normal seasonal variations of temperature were observed in all stations during the study period (except the station 13). In addition, the abundance of three species namely Pseudoamincola natolica natolica, Fagotia sangarica Schütt, 1974,

The measurements of DO in the Upper Sakarya River System showed minimum values in (summer) at station 5 and (autumn) at station 3, the maximum value is indicated at

Table 5: Pearson’s correlation coefficients between abundance of Gastropoda species and examined physico-chemical parameters of Upper Sakarya River System. Korrelationskoeffizienten nach Pearson zwischen der Abundanz der Gastropodenarten und den untersuchten physikalischchemischen Parametern im System des Oberen Sakarya River. Species pH

Temp

Prosobranchia Fagotia sangarica Melanopsis praemorsa costata Oxyloma elegans Pseudoamincola natolica natolica Sadleriana byzanthina Theodoxus heldreichi Valvata cristata Valvata piscinalis Valvata pulchella

0.413* ⫺0.27 ⫺0.221 ⫺0.39 ⫺0.004 ⴚ0.467* ⫺0.224 0.430* 0.176

0.706** ⫺0.154 ⫺0.284 0.685** 0.2 0.590** ⫺0.198 0.142 ⫺0.24

Pulmonata Bithynia badiella Galba truncatula Gyraulus albus Gyraulus ehrenbergi Physa acuta Planorbis carinatus Radix peregra

⫺0.173 0.268 ⫺0.085 ⫺0.084 ⫺0.216 0.203 0.332

0.297 ⫺0.162 ⫺0.347 ⫺0.22 0.234 0.241 ⫺0.072

** p < 0.01; * p < 0.05.


DO

0.479** 0.069 0.027 0.409** 0.007 0.524** 0.136 0.357 0.234 ⫺0.128 ⫺0.155 0.172 ⫺0.068 ⫺0.252 ⫺0.254 0.375

Parameter BOD

NO3⫺-N

NO2⫺-N

NH3

⫺0.122 ⫺0.102 0.042 ⫺0.186 ⫺0.186 ⫺0.173 ⫺0.141 ⫺0.201 0.226

0.206 ⫺0.096 0.594** 0.127 ⫺0.369 0.023 ⫺0.02 ⴚ0.488** 0.318

⫺0.167 ⫺0.106 ⫺0.021 ⫺0.145 ⫺0.106 ⫺0.184 ⫺0.147 ⫺0.171 0.098

⫺0.184 ⫺0.151 0.275 ⫺0.197 0.125 ⫺0.22 ⫺0.179 ⫺0.278 0.228

⫺0.168 0.191 ⫺0.249 ⫺0.143 0.244 0.247 ⫺0.384

0.101 0.611** ⫺0.104 ⫺0.039 0.357 0.359 ⴚ0.572*

⫺0.16 0.054 ⫺0.224 ⫺0.12 0.114 0.116 ⫺0.255

⫺0.216 0.377 ⫺0.255 ⫺0.116 0.25 0.254 ⫺0.035



station 1 (in spring sampling). Low DO values at stations 5 and 3 can be related to frequent wastewater discharges by the industrial organizations in this area, whereas station 1 a branch of Porsuk Stream and is not affected by pollution.

Acknowledgements

Dissolved oxygen levels of the water were a significant parameter for the abundance of especially Prosobranchia species [17, 23, 25]. The highest number of individua were observed in autumn sampling at the stations 5 and 13. Harman [23] indicated that some Prosobranchia species could be found in waters also with low DO levels. This knowledge supported our result. However, dissolved oxygen level of station 13 is ranging from 2.7 to 3.6 mg L⫺1, but BOD level ranged from 1.2 to 3.2 mg L⫺1, so the low DO level does not indicate organic pollution. Due to the measurements of DO and BOD, the stations 3 and 5 are significantly organic polluted. Especially in station 3 maximum BOD was determined and no Gastropods were found at this station. The other environmental parameters such as depth of the sampling sites and NaCl level were not significantly correlated (p > 0.05) with the abundance of Gastropoda species (results not shown in Table 1). The higher abundance of Gyraulus albus at the stations 3 and 16 with NH3 concentrations up to 7 mg L⫺1 in autumn ⫺ coming from domestic, industrial, and agricultural wastes ⫺ indicates that this species also spreads out in polluted waters. The Pulmonata species belonging to the genus Physa are considered as biological indicators of organic pollution and eutrophication [25]. In addition, G. albus was determined in polluted waters by Gallardo [24]. Our findings support this knowledge. Seasonally, only 5 species (Gyraulus albus, Physa acuta, Valvata cristata, Valvata pulchella, Melanopsis praemorsa costata) were determined each season. On the other hand, Planorbis carinatus Müller, 1774 was found only in Enne Stream in the fall and the summer seasons while Melanopsis paremorsa costata was identified just in the Sakaryat spring in all seasons. In addition, just in the spring studies, Sadleriana byzanthina in Özsuyu Creek, and only in the summer studies, Valvata piscinalis in Seydi Creek were determined. Spatially widespread at the 18 sampling sites are: Gyraulus albus (in 11 sites), Gyraulus ehrenbergi, Valvata cristata (in 8 sites), Valvata pulchella, and Physa acuta (in 7 sites). In contrast to this, Melanopsis praemorsa costata was determined only at station 13, as second abundant species. Valvata piscinalis was determined only at station 7. Furthermore, no Gastropoda were found at the station 3.

We are grateful to Dr. Mehmet Zeki Yıldırım, Süleyman Demirel University, Isparta-Turkey, who kindly provided laboratory facilities to me during my MSc thesis. He also helps in identification and confirmation. We would like to thank Dr Rıdvan S¸es¸en, Dicle University, Diyarbakır-Turkey, for identification of Sadleriana byzanthina. Lastly, we thank the Research Foundation of Osmangazi University for their funding.

References [1] Chapman, P. M., Farrell, M. A., Brinkhurst, R. O.: Relative tolerances of selected oligochaetes to individual pollutants and environmental factors. Aquat. Toxicol. 2, 47⫺67 (1982). [2] Goldberg, E. G.: The mussel watch concept. Environ. Monit. Assess. 7, 91⫺103 (1986). [3] Salańki, J.: New avenues in the biological indication of environmental pollution. Acta. Biol. Acad. Sci. Hung. 40, 295⫺328 (1989). [4] Borcherding, J., Volpers, M.: The “Dreissena-Monitor”. First results on the application of the biological early warning system in the continuous monitoring of water quality. Water Sci. Technol. 29, 199⫺201 (1994). [5] Girgin, S.: A comparation of diversity of benthic macroinvertebrates using different indices in Ankara Stream. Turk. J. Zool. 21, 269⫺274 (1997). [6] Kazancı, N., Girgin, S.: Distribution of Oligochaeta species as bioindicators of organic pollution in Ankara Stream and their use in biomonitoring. Turk. J. Zool. 22, 83⫺87 (1998). [7] Sözen, M., Yig˘it, S.: The benthic fauna and some limnological aspects of Lake Aks¸ehir (Konya). Turk. J. Zool. 23, 829⫺847 (1999). [8] Egemen, Ö., Önen, M., Büyükıs¸ık, M., Hos¸sucu, B., Sunlu, U., Gökpınar, S¸., Cirik, S.: Güllük Lagoon (Aegean Sea, Turkey) ecosystem. Turk. J. Agric. Forestry 23, 927⫺947 (1999). [9] Kazancı, N., Dügel, M.: An evaluation of the water quality of Yuvarlakçay Stream, in the Köyceg˘iz-Dalyan Protected Area, SW Turkey. Turk. J. Zool. 24, 69⫺80 (2000). [10] Polat, M.: Akarsu ve Göllerde ˙Izlenen Fiziksel ve Kimyasal Parametreler (Physical and chemical parameters observed in rivers and lakes). Su Kalitesi Yönetimi Semineri. T.C. Enerji ve Tabii Kaynaklar Bakanlıg˘i Genel Müd., Ankara, 1997, pp. 43⫺58. [11] Schütt, H.: Die Molluskenfauna eines reliktaren Quellsees der Südlichen Türkei. Arch. Molluskenkunde 93 (5/6), 173⫺180 (1964). [12] Schütt, H.: Zur Systematik und Ökologie Türkischer Süßwasserprosobranchier. Zool. Meded. 41 (3), 44⫺72 (1965).


400 Y. C ¸ abuk et al. [13] Geldiay, R., Bilgin, F. H.: Türkiyenin Bazı Bölgelerinden Tespit Edilen Tatlısu Mollusklları (Freshwater Mollusks collected from some parts of Turkey.). Ege Üniversitesi Fen Fakültesi ˙Ilmi Raporlar Serisi, No. 90, 1969. [14] Macan, T. T.: A Key to the British Fresh and Brackish Water Gastropods, No. XIII. Freshwater Biological Association-Scientific Publication No. 46, 1977. [15] Bilgin, F. H.: Batı Anadolu’nun Bazı Önemli Tatlısularından Toplanan Mollusca Türlerinin Sistematig˘i ve Dag˘ılıs¸ı (Systematics and distributions of Mollusca species collected from some freshwaters of West Anatolia). Diyarbakır Üniversitesi Tıp Fakültesi Dergisi. 8 (2), 5⫺64 (1980). [16] Schütt, H., S¸es¸en, R.: Theodoxus in South-eastern Anatolia, Turkey (Gastropoda Prosobranchia, Neritidae). Basteria 53, 39⫺46 (1989). [17] Yıldırım, M. Z.: Türkiye Prosobranchia (Mollusca: Gastropoda) Türleri ve Zoocog˘rafik Yayılıs¸ları I. Tatlı ve Acı sular (The Prosobranchia (Gastropoda: Mollusca) species of Turkey and their zoogeographic distribution 1. Fresh and brackish water). Turk. J. Zool. 23, 877⫺900 (1999). [18] Tabanchnick, B. G., Fidell, L. S.: Using Multivariate Statistics. Harper Collins College Publishers, New York, 1996. [19] Sharma, S.: Applied Multivariate Techniques. John Wiley and Sons, New York, 1996.


Acta hydrochim. hydrobiol. 32 (2004) 6, 393−400 [20] Rihard, A. J., Wichern, D. W.: Applied Multivariate Statistical Analysis. Prentice Hall, Englewood Cliffs, New Jersey, 1992. [21] T.R. Undersecretary of Environmental: Governing Statutes of Checking of Water Quality Pollution. Ankara, 1988. [22] Greenberg, A. E., Clesceri, C. S., Eaton, A. D.: Standard Methods for the Examination of Water and Wastewater. 18th Edition, APHA, AWWA, WEF, Washington, 1992. [23] Harman, W. N., in Haart, C. W., Fuller, S. L. H. (Eds.): Pollution Ecology of Freshwater Invertebrates, Snail (Mollusca:Gastropoda). Academic Press, London, 1974. [24] Gallordo, A., Prenda, J., Pujante, A.: Influence of some environmental factors on the freshwater macroinvertebrates distribution in two adjacent river basins under Mediterranean climate II. Molluscs. Arch. Hydrobiol. 131, 449⫺463 (1994). [25] Ertan, O. Ö., Yıldırım, M. Z., Morkoyunlu, A.: Konne Kaynag˘ı’nda (Eg˘irdir- Türkiye) Yayılıs¸ Gösteren Mollusca Türleri ve Beslenme Tipleri (The Mollusca species of Konne Spring (Eg˘irdir-Turkey) and their nourishment models). II. Uluslararası Su Ürünleri Sempozyumu. 21⫺23 Eylül ˙Istanbul, 1996. [Received: 14 July 2003; accepted: 8 June 2004]