The peatlands of Polesie—what is left and what is lost in terms of habitats and carbon stores over the last 100 years

Abstract One of the largest peatland complexes in Europe is located in Polesie. The most intensive drainage of this area has taken place in the last 100 years. At the turn of the 1920s and 1930s, Professor Kulczyński’s team carried out extensive studies of the western part of Polesie. We digitised and attached the maps and species lists published by Kulczyński. The results of this research served as the starting point for analysing vegetation changes over the last 100 years. Our estimates showed that 28–42% of the original mire area has survived to the present day, while the rest has been converted into arable fields, intensively used meadows and peat mines. Most of the remaining mires are located in large complexes. The vegetation within the present poor fens and bogs retained most of its natural characteristics. We observed changes in vegetation within the preserved rich fens – taxa associated with low-productivity rich fens are disappearing, while species indicative of drying and increased habitat fertility are increasing. The degradation of the Polesie peatlands has not only led to a loss of biodiversity but also has contributed significantly to climate change. In the period 1965–2023, the drained peatlands of this area may have emitted between 0.33 and 0.74 Gt CO 2 eq.