In this paper we report the results of interdisciplinary investigations of deposits filling small closed depressions in the Western Polesie region. There were reconstructed the environmental changes and the main evolution phases of four morphometrically similar forms (=research sites) situated in the Lublin and Volhynia parts of the Polesie region. The gathered sedimentological, chronostratigraphical, palynological and geochemical data evidence great lithological (peats, gyttja, calcareous tufa) and age (Late Glacial, Neoholocene) differences between the deposits filling individual forms and indirectly suggest their karstic origin.