Stratigraphy of peatbog of Gorobets River valley, and the development of the natural environment of Shikotan Island (Lesser Kuril Range) in the Holocene
The stratigraphy of peatbog of the Gorobets River valley, the largest river on Shikotan Island, is based on spore-and-pollen, diatomic, tephrostratigraphy and radiocarbon dating. The peat began to deposit in Early Holocene, and the place is the most ancient peatbog within the South Kuriles. Nine phases of vegetation development determined by climatic changes are defined. The age, the causes of appearance and disappearance of certain conifers, small-leaved and broad-leaved taxa, and the change of their role in the landscape formation are discussed. Specific features of formation of present-day vegetation of the Lesser Kuril Range as a separate floral region is shown. Besides the climatic changes and sea-level oscillations, relief, land size and the isolation factor played a great role in landscape development.