Holocene development of the Vistula Spit (Baltic Sea coast) based on multidisciplinary investigations

Abstract

Coastal barriers are the first line of defense for the mainlands against the impacts of severe storms, therefore the need for better understanding how barriers evolve is arising. Spits (barriers) are the dominant landform type of the southern and south-eastern Baltic Sea coast. The aim of this paper is to gain present a better insight into problems of the Vistula Spit origin in general, and especially on the age of formation of the dune ridges. The Vistula Spit is one of the largest barriers on the southern Baltic coast. The analysis comprised: OSL dating of dune sands, radiocarbon dating of peat and palynological studies of peat and fossil soil profiles. Results shows that the onset of the oldest dunes formation begun ca. 7000–6000 years ago and the highest ridge were formed ca. 4000–2000 years ago. The youngest dunes, located closest to the modern shore, formed in the past 2000 years. Aeolian processes were also activated locally and periodically as a result of forest wildfires and human activities. Vistula Spit emergence and development is connected to two global events; beginning of the oldest dunes formation is related to slowing down in the sea level rise around 7000–6000 years ago, whereas the onset of the highest dunes building can be clearly connected with the climate cooling and aridification around 4200 years ago.