Journal of the Institute of Science and Technology of Gazi University 1999, 12 (3), pp. 473–496. 1 A STUDY ON DIATOMS IN UPPER PART OF ÇORUH RIVER , TURKEY Tahir ATICI Department of Biology, Gazi Education Faculty, Gazi University, Beşevler ANKARA-TURKEY Olcay OBALI Department of Biology, Science Faculty, Ankara University, Tandoğan ANKARA-TURKEY ABSTRACT The diatoms of Çoruh River had been studied in samples, which were taken from different habitats (epipelic, epiphytic, epilithic, planktonic), from November 1994 to August 1996. A total of 106 taxa had been recorded in Çoruh River and 80 photographs of diatoms from the examined material have been given in 8 figures. Genera Nitzschia which has been represented in 16 species and Navicula which has been represented in 14 species are dominant at river. Key words : Diatoms, Çoruh River, Turkey ÇORUH NEHRİ YUKARI BÖLGESİ DİYATOMELERİ ÜZERİNE BİR ÇALIŞMA, TÜRKİYE ÖZET Çoruh Nehri Diyatomeleri, Kasım 1994 – Ağustos 1996 tarihleri arasında, seçilen istasyonlarda farklı habitatlardan (epipelik, epifitik, epilitik, plankton) alınarak incelenmiştir. Nehirde toplam 106 takson tespit edilmiş ve bunlara ait 80 fotoğraf 8 şekilde verilmiştir. Nitzschia 16 türle ve Navicula da 14 türle nehirde dominant cinsleri oluşturmaktadırlar. Anahtar Kelimeler : Diyatomeler, Çoruh Nehri, Türkiye