Dendrochronological study of the Sawicki landslide activity in the Beskid Niski Mts (Polish Flysch Carpathians)

The article presents the results of the dendrogeomorphological study of the activity of the Sawicki landslide, located in the Beskid Niski Mts (Polish Flysch Carpathians). The study was conducted within two study sites in the lower part of the landslide. The landslide movements were dated using the dendrogeomorphological method, basing on the eccentricity indicators calculated for the two coniferous species, i.e. Scots pine (Pinus sylvestris) and silver fir (Abies alba). It was found landslide activity in years: 1899, 1901, 1905, 1910, 1913–1914, 1920–1921, 1929–1931, 1935, 1937, 1945, 1977, 1979, 1981, 1984–1985, 1990, 1992–1993, 1997, 2003–2004, 2006, 2010–2012. The greatest activity was characterized for the northern part of the study site B and the south-western slopes of the Szklarki stream valley (study site A). Studies have shown only a partial dependence between precipitation and landslide episodes. The data were confronted with the results of dendrogeomorphological studies, conducted in the northern and central parts of the landslide. The results demonstrate the significant complexity of mass movements within large-area landslide.