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In this paper we restore moisture changes since the Younger Dryas based on the study of diatom flora in sediments of the Zelenyi coastal paleolake, the Lesser Kuril Ridge. The section includes numerous interlayers of tephra, the sources of which were located on the islands of Kunashir and Hokkaido, and interlayers of tsunamigenic sands, which made it possible to determine the impact of catastrophic events on changes in the ecological situation. The stages of the development of the lake are identified and its evolution is analyzed during short-period climatic rhythms. The reservoir had its maximal depth at the beginning of the Holocene, and planktonic forms predominated among diatoms. Three phases when the lake turned into a lagoon were established, and the erosion of the barrier form most likely caused this during large tsunamis associated with earthquakes. Except for these cases, the main factor leading to the change in lacustrine–marsh environments was climate change. We identified relatively dry periods and wet periods associated with an increase in the intensity of cyclogenesis in the South Kurils region. We correlated with high-resolution paleoclimatic records from archives for the Southern Kuriles; the most striking events were compared with data for Sakhalin and the continent. Changes in moisture on the islands and the margin of the mainland in the Middle–Late Holocene were established to be in antiphase in most cases, except for the cooling of 2800–2500 BP and the Little Ice Age. The connection of regional climatic changes with anomalies in the ocean and atmosphere of the Asia-Pacific region is shown. [ABSTRACT FROM AUTHOR]

Deserts and sandylands that are located in the semi-arid and arid regions in the middle latitudes of the Northern Hemisphere are usually regarded as environmentally sensitive change belts which respond to global climatic change. In northern China, activation or immobilization of sand dunes is mainly influenced by humid and dry variation and is related to stronger or weaker Asian monsoons. In this paper, the history of Holocene millennial-scale climatic and environmental change is reconstructed by the systematic analysis of the geochemical element contents and parameters, along with the OSL and C chronologies, from the different lithologies of the palaeosol-aeolian sand sequence in the south-eastern Mu Us Desert, northern China. Our results indicate that the region was dominated by a dry climate with intensive aeolian activity before 7.2 ka BP, and there was an optimal humid climate and fixed desert in 7.2-4.6 ka. Afterwards, the dune fields became mobile again as the effective humidity declined. Additionally, six dry events were discovered with times of ~7.2, 7.0-6.8, 6.6-5.7, 4.6-4.1, 3.7-3.5, and 3.3-2.5 ka, which were not only coincident with the intervals of millennial-scale weaker Asian summer monsoons, but also accordant with the cold events evidenced in the ice cores and deep-sea deposits of the high latitudes in the Northern Hemisphere. In general, the Holocene climatic and environmental changes had the characteristics of the 'monsoonal mode' and 'abrupt millennial-scale oscillation' in the Mu Us Desert. [ABSTRACT FROM AUTHOR]