Inferring conductivity and eutrophication in Turkish shallow lakes by using subfossil Diatoms

2016-08-31
Bezirci, Gizem
Sayer, Carl
Levi, Eti
Çakıroğlu, İdil
Bennion, Helen
Beklioğlu, Meryem
In recent years, paleolimnologists have the ability of making accurate environmental predictions using high quality data sets through the help of modern techniques and analytical methods for answering questions about past and present status of freshwater environments. Diatoms play an important role in freshwater ecosystems as being good indicators of water quality and they provide valuable information about current and past status of lakes due to their high sensitivity about shifts in trophic status of the environment. In this study, 47 shallow lakes from Turkey were sampled for water chemistry and sediments along a latitudinal gradient using space for time approach. Due to preservation issues, 36 lakes were used during the analyses. According to Redundancy Analysis (RDA) via forward selection, conductivity, total phosphorus (TP) and percent plant volume inhabited (PVI%) were the most important environmental variables influencing the distribution of diatoms with total of 36% of the variance. Additionally, two shallow lakes (Karagöl-İzmir and Karagöl-Bolu) were selected for further ecological reconstruction of the past status. Passive plotting of the core data onto RDA graph and comparison of bottom core with every upper sample using Square Chord Distance (SCD) revealed the changes through time for both lakes. It is found out that although conductivity is the main driver for present time, eutrophication had a significant impact on whole core during past. Eutrophic taxa were dominant for both cores with only compositional change through time. Moreover, transition between planktonic to benthic taxa addressed changes for water level.
3rd Ecology and Evolutionary Biology Symposium (31 Ağustos - 01 Eylül 2016)

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Citation Formats
G. Bezirci, C. Sayer, E. Levi, İ. Çakıroğlu, H. Bennion, and M. Beklioğlu, “Inferring conductivity and eutrophication in Turkish shallow lakes by using subfossil Diatoms,” presented at the 3rd Ecology and Evolutionary Biology Symposium (31 Ağustos - 01 Eylül 2016), Ankara, Türkiye, 2016, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/84538.