Sequence stratigraphy and environmental background of the late Pleistocene and Holocene occupation in the Southeast Primor'ye (the Russian Far East)

Tundra-forests with larch trees, dwarf birch thickets and polypod ferns from the basal stratigraphic units of the late Last Glacial occupation sites associated with the Upper Palaeolithic micro-blade and bifacial stone tool traditions (14C-dated to 19,000-12,000 cal yrs BP) indicate rather pronounced conditions and much lower MAT comparing today. Following a final Pleistocene cooling event, a major climate warming marked the onset of Holocene accompanied by a regional humidity increase promoting the formation of a mixed broadleaved-coniferous oak-dominant taiga, and culminating in the mid-Holocene Climatic Optimum. The appearance of mosaic parklands ca. 5,000-4,000 cal yrs BP. may be partly attributed to the expansion of the Far Eastern Neolithic cultures practicing forest clearance for pastures and dwellings. A progressing landscape opening indicated by the spread of light-demanding thickets and birch-dominated riverine biotopes with Artemisia suggests a further vegetation cover transformation during the late Neolithic and the early Palaeo-Metal (Bronze Age) periods. This trend corroborates the documented climate deterioration between 3,400 and 2,600 cal yrs BP, causing a regional aridification with a parkland-steppe broadening in the main SE Primor'ye river valleys. The late Holocene climate development persisted until the Little Ice Age which led to formation of the present settlement ecosystems with mixed (oak/cedar/fir-dominated) temperate maritime woodlands.