Tracking the recent historical changes in Turkish shallow lakes based on a palaeolimnological approach using diatoms

Bezirci, Gizem
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.


Zooplankton adaptation strategies against fish predation in Turkish shallow lakes
Yazgan Tavşanoğlu, Ülkü Nihan; Beklioğlu, Meryem; Jeppesen, Erik; Department of Biology (2012)
In this study, the factors influencing zooplankton community structure in Turkish shallow lakes were elucidated with four main approaches: (i) space-for-time substitution for shallow lakes using snap-shot sampling in 31 lakes along a latitudinal gradient; (ii) in-situ mesocosm experiments in eleven lakes along a latitudinal gradient using three sets of artificial plants systems; (iii)‘Habitat Choice’ laboratory experiments mimicking a ‘shallow littoral’ zone with plants and a ‘deeper pelagic’ zone with sedi...
Impacts of eutrophication and water level change in turkish shallow lakes: a palaeolimnological approach utilizing plant remains and marker pigments
Levi, Eti Ester; Beklioğlu, Meryem; Department of Biology (2016)
Current study provides further understanding of plant macrofossil and sedimentary pigment utilization in comparison with modern and historical environmental variables. Moreover, it contributes to investigations for determining suitable macrophyte-based indices (water framework directive-WFD) that can be employed in Turkey. In total 44 small and mostly shallow lakes, covering the whole latitudinal gradient at western half of Turkey were sampled with snap-shot sampling and from another set of three large lake...
Estimation of carbon dioxide flux in shallow lakes in Turkey
Kalvenas, Jennifer; Beklioğlu, Meryem; Department of Biology (2014)
The role of Turkish shallow lakes as a sink or source of carbon from 44 shallow lakes sampled once from 2006 – 2012 over six degrees of latitude is analyzed in terms of spatial resolution. Two of the lakes (Eymir and Mogan) were sampled over the spring, summer, and fall seasons from 2006 – 2010 under dry and wet periods and analyzed for temporal resolution. An equation using pH, specific conductivity, wind speed, temperature, and acid neutralizing capacity (ANC) was used to determine CO2 fluxes (Trolle et a...
The Integrated lake basin management planning : a study on the Beyşehir Lake basin
Altay, Ezgi; Gedikli, Bahar; Department of City and Regional Planning (2012)
This study aims at elaborating the Integrated Lake Basin Management Planning (ILBM) approach, which is considered as a sustainable management model for lake basins, and evaluating the applicability of this approach in Turkey. ILBM considers both biophysical features and managerial requirements of lake basin systems. It pays attention to inherent dynamics between humans and nature. ILBM has been developed on the basis of Integrated Water Resources Management (IWRM), which seeks the wise use of water; i.e. us...
Salinity inference in inland Turkish shallow lakes based on paleoecology using sub-fossil cladocera
Çakıroğlu, Ayşe İdil; Beklioğlu, Meryem; Jeppesen, Erik; Department of Biology (2013)
In the current study, sub-fossil Cladocera collected from the surface sediment of 44 shallow lakes spanning over five latitudes from north to south of Turkey using snap-shot methodology revealed strong impact of salinity on cladoceran community structure. To see the whole picture, sediment cores collected from six of the lakes and long-term monitoring data from two of the lakes were also investigated. Contemporary cladocerans and sub-fossil assemblages were compared to reveal that their responses to salinit...
Citation Formats
G. Bezirci, “Tracking the recent historical changes in Turkish shallow lakes based on a palaeolimnological approach using diatoms,” Ph.D. - Doctoral Program, Middle East Technical University, 2017.