Early Holocene vegetation and climate dynamics in the central part of the East European Plain (Russia)

摘要

This paper presents vegetation and climate reconstructions for the forest zone in the central part of the East European Plain, Russia, for the time period 10,000-7900 cal. BP. Reconstructions were based on pollen records from three key regions located in taiga, mixed coniferous-broadleaved and broadleaved forest zones. Results showed that the considered period was characterized by relatively low air temperatures and high precipitation compared with modern conditions. Analysis of the long-term pattern of the mean annual temperature for all three regions reveal two synchronous significant cooling periods observed 9300-9100 cal. BP and 8500-8100 cal. BP as well as rapid growth of the air temperature in 8100-7800 cal. BP, when the annual temperatures increased by 3 degrees C during about 300 years. The cooling phase of 8500-8100 cal. BP could correspond to the distinct "8.2 ka event" widely recorded across Europe. Periods of climate warming are coincided with periods of precipitation rise whereas the cool phases are characterized by its decrease. The ratio of actual evapotranspiration and precipitation amount selected as indicator of surface moistening conditions decreased significantly in period of cooling phases (down to 0.27) and can be used as a clear indicator of ground surface overwatering and strengthening of mire formation processes. (C) 2015 Elsevier Ltd and INQUA. All rights reserved.