The Unprecedented Current Increase in the Amount of Charcoal Particles in Sediments of Lakes of the North Minusinsk Basin (Southern Siberia): Possible Evidence of Anthropogenic Influence

Abstract

The distribution of charcoal particles >100 µm in size, which are indicators of plant combustion in ambient territories, are analyzed in sediments of Shira and Uchum lakes located in southern Siberia in the steppe zone of the North Minusinsk Basin (Republic of Khakasiya and Krasnoyarsk krai). The age of the lakes is to 1400 and 500 years, respectively. The lacustrine sediments contain charcoal particles of three types. Particles of group 1 have elongated morphology and are interpreted as remnants of grassy plants and/or conifers. Particles of group 2 look like thin plates similar to relics of leaves and bark of trees. Group 3 is composed of various irregular volumetric particles, which are probably relics from wood and coal combustion. The particles of group 1 are mostly indicators of natural fires, and their amount is almost constant in the current period. The amount of charcoal particles of groups 2 and, mostly, 3 has strongly increased in past 100 years, which reflects an increase in the amount of artificially combusted wood and coal in the vicinities of the lakes in the present-day industrial period. An increase in the contribution of the charcoal particles to lacustrine sediments over the past 100 years has been detected for the first time for this region, which is unprecedented for the period of study. This is evidence of the anthropogenic impact on the dynamics of charcoal particles in lacustrine sediments. Our data can be useful for reconstruction of the dynamics of natural fires and the paleoclimate in southern Siberia in the Late Holocene.