Multidisciplinary approach to studying the formation and development of beach-ridge systems on non-tidal uplifting coasts in Estonia

The coastal ridge–swale systems in the west Estonian archipelago (Röögu, Lõimastu) and on the northern coast (Juminda), where wave and wind-built ridges are separated from each other by wet depressions, contain the records on ancient shoreline positions, major storm events and forest fires. The results are based on cartographic analysis, ground-penetrating radar survey, coring and radiocarbon dating. Seaward tilted layers in lower parts of the ridges refer to storm scarps. Water level rise and acidic waters flowing from ridges favour the accumulation of Sphagnum peat in swales. The main soil-forming processes are podzolization on ridges and paludification in swales. The obtained results show a clear dependence of soil-forming conditions and development of peat layer on morphology and dimensions of landforms, character of parent material, vegetation type and groundwater table. Paludification will lead to a complete burial of the ridges under peat turning the areas to homogeneous bog landscape.