Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Fen Edebiyat Fakültesi, Biyolojik Bilimler Bölümü, Türkiye
Tezin Onay Tarihi: 2017
Öğrenci: GİZEM BEZİRCİ
Danışman: MERYEM BEKLİOĞLU
Özet:Current study provides information about the factors that influence the diatom composition of shallow lakes in Turkey. Thirty two shallow lakes were sampled with snap-shot sampling. Moreover, short cores from four small shallow lakes and three large lakes were retrieved. The study showed that conductivity had a significant impact on shaping the fossil diatom composition in surface sediment samples and the effect of eutrophication was captured in short core samples especially after 1970s for altering the past status of Turkish shallow lakes. The complex interactions of biological remains and environmental variables were also revealed.The comparison of instrumental waterlevel data (40-100 years) with fossil diatom samples showed the reflection of short term water level changes in sediment cores was rather poor but the negative impact of eutrophication was hinted especially for Lake Uluabat and Lake Marmara. vi The current study suggested that diatom fossils are good indicators for capturing the environmental variations and can be used in the absence of historical data for tracking the historical changes of shallow lakes in Turkey. However, to achieve clear signs of the composition alteration, a long-term perspective is needed and the complexity of multiple drivers for shaping the community structure of the diatom flora should be considered. In addition, the significant influence of conductivity and nutrients emphasizes the expected impacts of climate change on Mediterranean region.