No abstract

It is important to determine the water quality of the creeks in the Lake Sapanca basin since it is used for drinking water supply. For this purpose, environmental parameters and diatom assemblages as biological quality components were investigated to determine the ecological status of eight creeks with monthly intervals between March 2015 and February 2016. During the studied period, 19 taxa increased their relative abundance higher than 30% in at least one sample and showed a different seasonal pattern. Main nutrients [(nitrate-nitrogen, orthophosphate, total phosphorus (TP)] and some other parameters (specific conductance, temperature, pH, and dissolved oxygen) had strong impacts on the distribution of diatom assemblages. The ecological status of the creeks was characterized by using four different diatom indices, however, only Trophic Index Turkey (TIT) represented significant positive correlations with log (TP) gradient and separated the creeks as good and moderate ecological status. According to TIT, the 4th and 6th stations had a good ecological condition and were characterized by pollution-sensitive species such as Cymbella affinis, Reimeria sinuata, and Nitzschia dissipata. On the other hand, TIT resulted in the other stations having moderate ecological conditions, which had high nutrient levels and EC. Moreover, the occurrence of pollution-tolerant taxa such as Gomphonema angustatum, Ulnaria ulna, and Achnanthidium affine endorsed the moderate ecological conditions in these creeks. Based on the results, the TIT as a biological metric could be a useful tool for the assessment of running waters in the Sakarya river basin.

Turkish lakes which have different morphometry and hydrology, have a great potential that supports distinct algal diversity as a result of different climate types and geographical variation (latitudinal, longitudinal, and altitudinal gradients). However, the algal flora of Turkey has not been completed, and the number of new taxa has increased due to new studies in Turkey. This study aims to describe new planktonic algal taxa for the Turkish freshwater algal flora. A total of 330 Chlorophyta, 164 Cyanobacteria and 187 Euglenozoa taxa were determined in a study conducted from 2017 to 2019 in 275 lakes of 25 river basins of Turkey. During this study, 116 Chlorophyta, 41 Cyanobacteria, and 81 Euglenozoa were found new records for the freshwater algal flora of Turkey.