Effects of salinity tolerances on survival and life history of 2 cladocerans

Salinity alterations in freshwater ecosystems greatly affect the survival and life history of zooplankton and, therefore, have an effect on higher trophic levels. Salinity is an essential and critical factor in determining the presence, dominance, and succession of organisms. After being collected in the field, Scapholeberis mucronata and Simocephalus vetulus were brought to the laboratory in water. Under laboratory conditions (24 ± 1 °C; 16:8 h photoperiod), we evaluated the effect of different salt concentrations on the neonates. The LC50 values were determined at different halotolerance levels for S. mucronata (0.375 g L-1) and S. vetulus (0.250 g L-1). Results of experiments demonstrated that S. vetulus was more sensitive than S. mucronata, which has hyponeustonic behavior. Morphometrics of the body in salinity stress were measured for S. mucronata. In the measurements of body length, body width, and spine lengths, there were significant differences determined by post hoc analysis between the control, 0.250, and 0.375 g L-1 dose groups and the 0.500 and 0.625 g L-1 dose groups. However, no clear relation between ovum size and salinity concentration was found. This study demonstrated how an increase in salinity significantly affects survival and life history properties, which can cause changes in the zooplankton community structure.

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Key words: Scapholeberis mucronata, Simocephalus vetulus, salinity gradient, population growth, survival parameters, morphometry

Effects of salinity tolerances on survival and life history of 2 cladocerans

Keywords:

Key words: Scapholeberis mucronata, Simocephalus vetulus, salinity gradient, population growth, survival parameters, morphometry,

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Ak I, Cirik S, Göksan T, Koru E (2012). Effect of salinity on growth characteristics and pigment composition of two strains of Dunaliella viridis Teodoresco: laboratory and outdoor studies. Fresen Environ Bull 21: 337–342.
Antunes SC, Castro BB, Goncalves F (2004). Effects of food level on the chronic and acute responses of daphnids to lindane. Environ Pollut 127: 367–375.
Black AR, Dodson SI (1990). Demographic costs of Chaoborusinduced phenotypic plasticity in Daphnia pulex. Oecologia 83: 117–122.
Brucet S, Boix D, Quintana X, Jensen E, Nathansen LW, Trochine C, Meerhoff M, Gascón S, Jeppesen E (2010). Factors influencing zooplankton size structure at contrasting temperatures in coastal shallow lakes: implications for effects of climate change. Limnol Oceanogr 55: 1697–1711.
Cowgill JM (1987). Critical analysis of factors affecting the sensitivity of zooplankton and the reproducibility of toxicity test results. Water Res 21: 1453–1462.
De Coen WMI, Janssen CR (2003). The missing biomarker link: relationships between effects on the cellular energy allocation biomarker of toxicant-stressed Daphnia magna and corresponding population characteristics. Environ Toxicol Chem 22: 1632–1641.
De Decker P (1983). Notes on the ecology and distribution of nonmarine ostracods in Australia. Hydrobiologia 106: 223–234.
Dodson SI, Frey DG (2001). Cladocera and other Branchiopoda. In: Thorp JH, Covich AP, editors. Ecology and Classiﬁcation of North American Freshwater Invertebrates. New York, NY, USA: Academic Press, pp. 849–913.
Dumont HJ, Negrea SV (2002). Introduction to the class Branchiopoda. In: Dumont HJF, editor. Guides to the Identification of the Microcrustaceans of the Continental Waters of the World. Leiden, the Netherlands: Backhuys Publishers.
El-Deeb Ghazy MM, Habashy MM, Kossa FI, Mohammady EY (2009). Effects of salinity on survival, growth and reproduction of the water flea, Daphnia magna. Nature and Science 7: 28–42. Finney DJ (1971). Probit Analysis. Cambridge, UK: Cambridge University Press.
Gliwicz ZM (2003). Between Hazards of Starvation and Risk of Predation: The Ecology of Offshore Animals (Excellence in Ecology, Volume 12). Oldendorf/Luhe, Germany: International Ecology Institute.
Gonçalves AMM, Daniela R, Pereira FMJ (2012). The effects of different salinity concentrations on growth of three freshwater green algae. Fresen Environ Bull 15: 1382–1386.
Grzesiuk M, Mikulski A (2006). The effect of salinity on freshwater crustaceans. Pol J Ecol 54: 669–674.