Varved sediments of Lake Gorzyńskie, western Poland: a new archive of climatic and environmental changes during the Late Glacial and the Holocene in central Europe

In this study, we present a newly discovered varved sediment site located in western Poland, where such records are scarce. The sediment profile from Lake Gorzyńskie is 10.45 meters long and covers the last ca. 13,250 years. Using varve counting and varve thickness measurements together with radiometric dating ( ¹⁴ C, ²¹⁰ Pb, ¹³⁷ Cs), a robust age-depth model was developed. Sediment lithology, varve microfacies, and statistical analysis of the chemical composition allow the identification of six depositional phases: the late Allerød (≈ 13,250–12,675 cal BP), the Younger Dryas (12,675–11,600 cal BP), the early Holocene (11,600–9,100 cal BP), the main part of the Holocene (9,100–2,250 cal BP), and two phases of the late Holocene (2,250–750 cal BP, 750 cal BP–present). The Younger Dryas is remarkably well recorded with a pronounced increase in allochthonous deposition followed by stable sedimentation during the early Holocene and by increased variability since 9,100 cal BP. Short-term fluctuations coinciding with known paleoclimatic events such as the Preboreal Oscillation and the 10.3 k climate event, are also evident. Distinct changes during the late Holocene are associated with increasing human impact. The Lake Gorzyńskie sediment record offers not only insights into long-term trends of the environmental history in western Poland but also into short-term paleoclimate variability since the Late Glacial.