Late Glacial and Early Holocene palaeoenvironmental changes in the Kuyavian Lakeland, Smólsk site, central Poland

Abstract

High-resolution biological proxies (pollen, macrofossils, Cladocera, Chironomidae, malacological analysis and diatoms), geochemical analyses, and AMS radiocarbon dating were employed to reconstruct the responses of the Smólsk palaeolake (Kuyavian Lakeland, central Poland) to rapid climatic and environmental changes during the Late Glacial-Early Holocene transition. The integration of palaeoecological and geochemical data enabled detailed insights into the dynamics of short-term shifts in terrestrial and aquatic ecosystems triggered by abrupt climate events. Precise age control and high-resolution sampling allowed the identification of temporal leads and lags between proxy responses to climatic shifts during this transitional period. Key findings include: (1) the coolest lake development phase, corresponding to the Late Glacial (9.050–5.400 m; 13,835–12,800 cal14C BP); (2) evidence of an open landscape and decreased water levels in the Late Glacial, resulting in intensified catchment erosion; (3) a change in sediment deposition at a depth of 5.35 m (~11,000 cal14C BP), marked by a transition from silt to calcareous gyttja and peat, indicating a lowering of groundwater levels and improved climatic conditions at the beginning of the Holocene; (4) a hiatus between the Late Glacial and Early Holocene recorded across all proxies; and (5) progressive eutrophication during the Holocene, characterized by reed belt development, reduced sedimentation, and the cessation of terrigenous sediment input. These findings highlight the lake system’s sensitivity to rapid climatic and environmental changes during this critical period.