Use of ephilithic diatoms as indicator for determining the water quality of 8 streams in Lake Sapanca

This study was carried out to determine the water quality of 8 streams in Lake Sapanca Basin between March 2015 and February 2016. Water temperature, specific conductance, total dissolved solid, pH and dissolved oxygen were measured monthly using a YSI proplus water probe. Chemical analyzes of waters were done monthly according to standard methods. The diatom samples were cleaned using HCl and H2O2. Cleaned diatom suspensions were dried onto glass coverslips and mounted in DPX. Then the slides were investigated using light microscope using 400× and 600× magnification. In addition todetermine the community composition, diversity and abundance of the epilithic diatoms, TIT (Trophic Index Turkey), EPI-D (The eutrophication/Pollution Index-Diatom), IPS (Index of Pollution Sensitivity) and TDI (Trophic Diatom Index) indexes were used to evaluate the ecological status of these streams. Moreover, the relationship between physicochemical data and diatoms were investigated. As a result, 132 taxa were identified from different genera in diatoms. During the study, Achnanthidium minutissimum and Cocconeis placentulawere determined as dominant taxa.Physicochemical analyzes indicated that the water quality of these stations were 1st and 2nd class. TIT, EPI-D, IPS and TDI indexes were categorized these 8 streams as medium status. Keywords: Lake Sapanca, Diatom, Water Quality, TIT, Ecological Status, Streams