Unveiling the Past: A Comprehensive Study of Büyükçekmece Lake's Evolution through High-Resolution Pollen and Multi-proxy Analysis during the Late Holocene

Abstract

Abstract Büyükçekmece Lake is located 35 kilometers west of the Bosporus in Istanbul and connected to the Marmara Sea, stands as an intriguing site for archaeological and geological exploration. Despite its proximity to significant historical sites, the lake's evolutionary history remains largely uncharted due to a dearth of limnological and geological investigations. Büyükçekmece Lake, with an average depth of approximately 8.6 meters, has witnessed fluctuations in water levels shaped by the dynamic interplay of warm and cool climatic factors. This investigation aims to unravel the specific timing of these changes and their correlation with regional climate, shedding light on the lake's geological conditions. The aim is to fill a gap in knowledge by conducting a high-resolution pollen analysis, never conducted for Lake based on the sediment core taken from Lake Büyükçekmece. Additionally, the research is supported by multi-proxy techniques such as the MSCL core logger for measuring magnetic susceptibility and density, as well as XRF elemental analysis.  Between 37.8-7 cm in the core, high XRF counts of in K, Fe, Si, Mn, and Ti are linked to a high abundance of detrital input. Ca values also increase in these depths and lower part of the core, suggesting that high Ca values can be related to abundance in bivalve shells. To achieve this goal, this study analyzed two sediment cores collected from Lake Büyükçekmece. The analysis involved multiple parameters, primarily focusing on sedimentology, alongside physical and geochemical characteristics. This study was granted by Istanbul Technical University, Scientific Research Projects (BAP) Unit with Project number: MYLB-2023-45169. Keywords: Pollen analysis, Paleoclimate, Lake Büyükçekmece, Türkiye, Late Holocene