Аннотация:The influence of the activation of explosive volcanism (536 AD) and the subsequent cooling on the ecosystems of peat bogs that formed on the territory of Russia was investigated. The studied peat strata of two bogs had coordinates (55° N, 88° E, and 58° N, 38° E, Kemerovo and Yaroslavl regions). The position of the peat horizons presumably corresponds to the 536 event and was determined by the radiocarbon method. The bottom of these horizons was respectively located at a depth of 120 cm and 105 cm. Micromineralogical studies showed that at these depths peat is enriched in ferro-silicate spherules with a diameter of 0.1-10 microns and is characterized by a relatively high remanent magnetization and density. The thickness of the layer enriched in ferro-silicate spherules and having a relatively high remanent magnetization is on average 7 cm. The thickness of the layer with increased density was 10-20 cm. The probable time interval between the change and restoration of ecosystems was about 200 years. Keywords: explosive volcanism, global cooling, peat bogs, microspherules