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  • Küçük Resim
    Öğe
    Contribution to the freshwater ostracoda (crustacea) fauna of Turkey : distribution and ecological notes
    (2014) Rasoulı, Hamidreza; Aygen, Cem; Külköylüoğlu, Okan
    Bu çalışmada, 31 Ağustos 2010 ile 23 Haziran 2011 tarihleri arasında 47 istasyondan toplam 37 tatlısu ostrakot türü toplanmıştır. Bunlardan üç tür (Eucypris kerkyrensis, Cypridopsis elongata, Bradleystrandesia parva) Türkiye ostrakot faunası için yeni kayıttır. Üç türün (Ilyocypris inermis, Trajancypris serrata ve Psychrodromus olivaceus) eşeysel popülasyonuna ise Türkiye’de tekrar rastlanılmıştır. Spearman Rank Correlation analizi, en sık rastlanılan dört tür (Condona neglecta, Heterocypris salina, Eucypris lilljeborgi ve Potamocypris villosa) ile elektriksel iletkenlik arasında anlamlı bir korelasyon gösterirken, sıcaklık ile bu türlerin rastlanılması arasında hiç bir anlamlı ilişki göstermemektedir. Çevresel değişkenler ile hiç bir korelasyon göstermemiş olan beş tür bulunmaktadır (Pseudocandona albicans, Ilyocypris gibba, Heterocypris incongruens, Heterocypris rotundata ve Eucypris virens). Ancak Potamocypris villosa türü üç değişken (pH, elektriksel iletkenlik ve tuzluluk) ile güçlü bir ilişki göstermiştir. Çevresel Tolerans İndeks (ETI) değerlerine bakıldığında, geniş dağılıma sahip olan (kozmopolit) çoğu türün aynı zamanda yüksek ETI değerine de sahip olduğu görülmektedir. Bu gibi toleransı yüksek ve geniş dağılımlı türlere “cosmoecious species” denilmektedir.
  • Küçük Resim Yok
    Öğe
    Contribution to the Freshwater Ostracoda (Crustacea) Fauna of Turkey: Distribution and Ecological Notes
    (Central Fisheries Research Inst, 2014) Rasouli, Hamidreza; Aygen, Cem; Kulkoyluoglu, Okan
    In this study, a total of 37 freshwater ostracod species were collected from 47 stations between 31 August 2010 and 23 June 2011. Among them, three species (Eucypris kerkyrensis, Cypridopsis elongata, Bradleystrandesia parva) were new records for the Ostracoda fauna of Turkey. Bisexual populations of three species (Ilyocypris inermis, Trajancypris serrata and Psychrodromus olivaceus) were repeatedly occurred from Anatolia. Spearman Rank Correlation analyses illustrated a significant correlation for the four most abundant species (Condona neglecta, Heterocypris salina, Eucypris lilljeborgi and Potamocypris villosa) with electrical conductivity while temperature did not show a significant effect on species occurrence. Five species (Pseudocandona albicans, Ilyocypris gibba, Heterocypris incongruens, Heterocypris rotundata and Eucypris virens) did not have any significant correlation to those variables used here, but correlation was significant between Potamocypris villosa and three variables (pH, electrical conductivity and salinity). According to Environmental Tolerance Index (ETI), most species with high ETI values were widespread species. Such species with high tolerance and widespread (or cosmopolitan) distribution were named as cosmoecious species
  • Küçük Resim
    Öğe
    Taxonomy, distribution, and ecology of crustacean zooplankton in trough waters of Ankara (Turkey)
    (Tubitak Scientific & Technical Research Council Turkey, 2014) Başak, Elif; Aygen, Cem; Külköylüoğlu, Okan
    Troughs are one of the main components of villages in Turkey. They are constructed by converting springs or underground waters. Until now, there has been no extensive study investigating the composition and diversity of trough zooplankton species. In order to contribute knowledge on the zooplanktons in troughs, 142 troughs were randomly sampled from 17 districts in Ankara Province between 22 June and 3 July 2011. A total of 18 zooplanktons including 11 Copepoda and 7 Cladocera species were determined. Twelve of the 18 (Paracyclops chiltoni, Paracylops fimbriatus, Paracyclops imminutus, Tropocyclops prasinus, Diacyclops bisetosus, Acanthocyclops vernalis, Canthocamptus staphylinus, Attheyella crassa, Bryocamptus minutus, Macrothrix hirsuticornis, Oxyurella tenuicaudis, Moina macrocopa) are new records for Ankara. Paracyclops imminutus was reported for the third time in Turkey in the last 50 years. UPGMA illustrated 4 main clustering groups of species corresponding to some of their ecological characteristics. Poisson distribution analysis showed almost random distribution of species among the troughs (s(2)/mu = 1.04). With their cosmopolitan characteristics, 3 species (M. hirsuticornis, E. serrulatus, and C. sphaericus) are the most common species. Their ecological tolerance and optimum values were higher than the mean tolerances for different environmental variables. The results show that troughs may provide suitable conditions for zooplankton species.