Colonisation of Epipelic Diatoms on the Littoral Sediments of izmit Bay

Seasonal variations in the composition, density and diversity of the epipelic diatom assembl ages were investigated monthly from March, 1999, to September, 2000, at 8 sampling sites chosen in the littoral of Üzmit Bay. The main physical and chemical parameters, which affected species composition and density, were also measured on every sampling date. During the study period,3 centric and 41 pennate diatoms were recorded in the epipelic diatom flora of the bay. Achnanthes Bory spp., Amphora exigua W.Greg. and Navicula tripunctata (O.M.ll.) Bory were dominant in terms of frequency and density. In general, the bay showed asmall species diversity in epipelic diatoms (annual mean 1.46 ± 0.44 bits ind-1). In addition to marine diatoms, freshwater specieswere also recorded in the epipelic diatom assemblages.