Allochthonous biofossil distribution in the blanket peat bog of Bolshoy Shantar Island was used to analyze atmospheric circulation anomalies in the north-western Okhotsk Sea over the last 12.6 ka. The main aim of this study was to determine periods of intensification of deep cyclones and extreme storms. The composition of bioaerosols is significantly influenced by atmospheric zonal and meridional transport anomalies associated with anomalies of the monsoon system of Northeast Asia, atmospheric fronts and cyclone trajectories. Marine diatoms enter the peatland from the sea during extreme storms and record the passage of sea cyclones in the autumn-winter, whereas the distribution of allochthonous pollen indicates the intensity of continental cyclones. We used Pinus pumila pollen as an indicator of heavy snowfalls and winter cyclone activity. Fifteen phases of extreme storms were identified. Changes in ice coverage also played an important role in bioaerosol emission. During cold periods, emissions of bioaerosols mainly occurred in the open sea, whereas during warm periods, emissions occurred near the coast. The recurrence and intensity of cyclones during the cold seasons depends on displacement of the Siberian High and Aleutian Low. Periods of continental cyclones intensified in spring-summer and coincided with periods of active winter cyclogenesis.

Based on studying the diatom flora by use of the radiocarbon dating methods, tephrostratigraph and other available biostratigraphic data, we reconstructed the settings of development of peat deposits

Paleotsunami remains have been studied in Middle/Late Holocene peat bogs and lacustrine deposits on Shikotan I. We determined the age of the events, the inundation areas, and the distance the tsunami waves traveled on shores of varying structures. The frequency of tsunami occurrence was nonuniform; these events were the most frequent in the middle of the Late Holocene. Data are provided for specific areas of the island’s coast, sequences have been identified containing numerous interbeds of tsunamigenic sand, which can be used as markers. The composition of the tsunamigenic sand has been analyzed to reveal its similarities with and differences to other coastal marine facies and to determine the sources of the material. These data could serve as a basis for compiling a highly detailed geological record of these events for the southern Kuril region during the last 6000 years.

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The deposits of the Tohoku Tsunami were studied on the Kunashir, Shikotan, Zelenyi, Yurii, and Tanfil’ev islands. They were sampled immediately after this event from ice, half a year later, and one and a half years later. The sampling was accompanied by measurements of the runup heights and the description of the innudation zones. Sand and mud covers were recorded only in closed bays that were covered by ice. The tsunami waves broke the ice cover to provoke bottom erosion and peatland destruction in low coastal areas even under insignificant runup. The investigations included the analysis of the grain-size distribution in the deposits and the taxonomic composition of the microfossils, including benthic foraminifers, diatoms, and pollen assemblages. The marine diatom assemblages are dominated by sublittoral benthic forms accompanied by subordinate sublittoral planktonic, neritic, and oceanic species. The palynospectra include pollen and spores of the local island vegetation, allochthonous pollen transported by the tsunami wave and wind from adjacent areas, and taxa reworked from the upper Holocene deposits eroded by the tsunami. The examined sections have been revisited to estimate the degree of preservation of the tsunamigenic deposits.

На основе биостратиграфических анализов (ботанический, диатомовый, спорово-пыльцевой) выделены этапы развития биотических компонентов болотного массива и окружающих горных склонов за последние 5120 кал. лет. Изученный разрез находится в верхней части болотного массива пади Васькова, в истоках ручья, впадающего в оз. Васьковское, на берегу которого расположена научно-экспериментальная станция «Смычка» ТИГ ДВО РАН. Возраст палео­ландшафтных смен определен по модели «глубина-возраст» на основе радиоуглеродного датирования. При оценке проявления наводнений использована величина зольности торфа. Проанализирован ход короткопериодных разнонаправленных климатических изменений, влиявших на развитие и смену растительности периферийной части биосферного района вблизи морского побережья. Большое влияние на развитие биотических компонентов оказывало изменение температурного фона, а также увлажнение, связанное с интенсивностью летнего муссона и активностью циклогенеза. Выделены периоды обводнения и относительного иссушения болотного массива, развивавшегося в условиях контрастных сезонных изменений. Установлены периоды, благоприятные для развития неморальных лесов, распространения кедра корейского и темнохвойных. Наиболее активное распространение темнохвойных лесов и кедра корейского на окружающих склонах наблюдалось в малый ледниковый период, оказавший большое влияние на становление современных ландшафтов. С 2900 кал. л.н. большую роль в развитии ландшафтов стал играть пирогенный фактор, что способствовало развитию вторичных березовых лесов. Предполагается, что пожары в основном имели антропогенную природу. Обнаружены палинологические признаки присутствия древнего человека. Отмечена тенденция к снижению увлажнения Васьковского болота и частоты наводнений за последние 200 кал. лет. Снижение доли пыльцы темнохвойных в конце XIX–XX в., вероятно, фиксирует вырубки при освоении района со времен переселенцев и организации горнорудного производства. По присутствию морских диатомей, перенесенных в виде морских биоаэрозолей, выявлены периоды усиления ветровой и штормовой активности, проявлявшиеся в похолодания. On the basis of biostratigraphic analyses (botanical, diatom, pollen) the stages of development of biotic components of the peatland and surrounding mountain slopes for the last 5120 cal. years have been identified. The studied section is located in the upper portion of the Vaskova Valley peatland, in the headwaters of the stream flowing into Vaskovskoye Lake, on the shore of which the Smychka Research and Experimental Station of the PGI FEB RAS is located. The age of paleolandscape shifts was determined by the depth-age model based on radiocarbon dating. The value of ash content was used to assess the occurrence of floods. The course of short-term climatic changes that influenced the development of vegetation within the peripheral part of the Biosphere Region near the sea coast was analyzed. The development of biotic components was greatly influenced by changes in the temperature background, as well as moistening associated with the intensity of the summer monsoon and the activity of cyclogenesis. Periods of watering and relative drying of the swamp massif, which developed under conditions of contrasting seasonal changes, were identified. Periods favorable for the development of nemoral forests, the spread of Korean pine and dark conifers were revealed. The most active spread of dark coniferous forests and Korean pine on the surrounding slopes was observed during the Little Ice Age, which had a great influence on the formation of modern landscapes. From 2899 cal. yr BP, the pyrogenic factor began to play a major role in the development of landscapes, which contributed to the formation of secondary birch forests. It is assumed that the fires were mainly anthropogenic. Pollen records of ancient human presence have been found. Over the last 200 cal. years, a tendency of decreasing moistening of the Vaskovskoye Peatland was noted, and the frequency of floods became lower. Reduce in the dark conifer pollen at the end of the XIX-XX century probably records felling during the development of the area since the time of...