Postglacial environmental change in the valley of Malye Chily River (the basin of Lake Teletskoye), northeastern Russian Altai

摘要

The evolution and current state of landscapes around Lake Teletskoye have not previously been studied in detail. In the valley of the Malye Chily River, which flows into Lake Teletskoye, the timing of dam failure and draining of two morainedammed lakes has been identified. Botanical analysis, ash content determination, and radiocarbon dating of two peat profiles provide insight into postglacial evolution of wetlands related to this landscape. We found clear evidence of the disappearance from the peat of higher vascular species that, today, grows mostly in the plains of Siberia. Correlation of the data obtained with the accepted chronology of the Holocene events in the Russian Altai suggests the following stages of postglacial environmental change in the Malye Chily River valley: (1) the continuation of the Late Würm glaciation degradation (before 7000 cal. yr BP); (2) Holocene Climate Optimum (7000–5000 cal. yr BP); (3) Akkem cooling (5000–4200 cal. yr BP); (4) warm period (4200–3700 cal. yr BP); and (5) Historical cooling (3700–1600 cal. yr BP).