Middle Miocene palynoflora from the Adamów lignite deposit, central Poland

The first mid-Polish group is the youngest among the main Neogene lignite seams in Poland. Lignites of this group developed in the middle Miocene over almost the whole of Poland, and therefore they are an important correlation horizon throughout much of the Polish Lowlands. A total of 30 palynological samples from the 3-metre seam from the Adamów deposit (central Poland) were studied in detail. The results revealed the presence of wetland and mesophytic vegetation during the time of sedimentation. The study area was overgrown by palustrine wetland communities similar in their composition to modern pocosins. The climate was warm temperate and humid, which was inferred from the palynoflora composition, including frequency of palaeotropical and palaeotropical/warm-temperate taxa, and the presence of epihyllous fungi. The estimated mean annual temperature (MAT) for the lignite seam at Adamów is 15.7–18.0 °C. Comparison with other palynofloras from the first mid-Polish lignite seam group shows that the climate was more or less homogenous within the entire Polish Lowlands during formation of the group of seams. The MAT ranges are also similar to other results from middle Miocene of Central Europe. The differences between the Adamów palynoflora and palynofloras from central and western Poland, dominated by swamp forests, most probably reflect the succession of plant communities in different hydrological and trophic conditions.