Pollen analysis was performed on 14 profiles of fossil biogenic sediments from different parts of the vast depression near the Wola Starogrodzka village (Central Poland). The results allowed the determination of the time of their accumulation for the period from the end of the Odra Glaciation (Warta Stage, Saalian, MIS-6), through the Eemian Interglacial (MIS-5e), to the first interstadial of the Early Vistulian (Brørup, MIS-5c). In many studied profiles, we noted the incompleteness in the pollen record of the Eemian vegetation succession – hiatuses occur usually in the hornbeam (E5) and/or spruce phase (E6). Moreover, the thickness of the same pollen zone and the development of its palynological record are strongly differentiated between individual profiles, e.g. the hornbeam zone (E5) is contained in an exceptionally thick sediment layer (3.7 m) in the PWS1-19 profile, and the oak zone (E3) in the WH-123 and PWS2-19 profiles (1.0 and 1.2 m, respectively), while in other profiles they are represented only by single pollen spectra. If we only had a single profile with a hiatus and/or a poorly developed pollen record, it would be impossible to reconstruct a complete interglacial succession of vegetation. However, having several such imperfect profiles which complemented each other enabled us to do it.

The aim of this study was to reconstruct the evolution of the Eemian palaeolake in the Żabieniec site (Garwolin Plain, Central Poland); it identifies changes in the water level and the trophic status of the lake resulting from panregional factors, including climate changes occurring during individual phases of the last interglacial, and local geologic-geomorphological factors shaping the palaeoenvironment using multi-proxy methods (palaeobotanical analyses, subfossil Cladocera and diatoms analyses as well as determinations of the stable isotopes). A record was obtained of all seven Regional Pollen Assemblage Zones (RPAZs) according to Mamakowa’s description of the Eemian pollen succession (1989), and of the changes in microfossil assemblages and isotopes in palaeolake sediments associated with lake evolution. Special attention was paid to the Middle Eemian RPAZ 4 (i.e. hazel phase) of the climatic optimum; all proxies associate this with the highest water level and a warm humid climate. During the E5/E6 RPAZs, the eutrophic lake transformed very quickly, and a transitional peatbog was formed. The higher humidity of the late Eemian resulted in another increase in water level. The multi-proxy record of the Żabieniec palaeolake which we obtained was compared to those of other Eemian water bodies in the Garwolin Plain and in Central Poland that exhibit sedimentation gaps especially during the younger part of the E5 RPAZ.