Landscape Changes in the Southern Mainland Russian Far East during the Little Ice Age

The article analyzes manifestations of the Little Ice Age in the southern mainland Russian Far East. The study is based on a synthesis of paleogeographic data, which, in the absence of historical records, are the most informative source for reconstructing environmental changes. The primary natural archives are deposits of mountain lakes and peatlands situated across different landscape belts of the low- to mid-elevation zones of the Sikhote-Alin and East Manchurian Mountains (at elevations of 300 to 1600 m). Changes in the composition of diatom flora, as well as components of forest and peatland ecosystems, provide the data to reconstruct abrupt climate shifts that took place from the 12th–13th centuries onward, including the transition from the Medieval Climate Anomaly. It is established that the late medieval cooling in the southern Russian Far East was wet, characterized by increased precipitation, including winter snowfall, and frequent flash floods. This baseline was punctuated by short-term intervals of reduced moisture availability and seasonal droughts. These drier conditions typically coincided with solar activity minima. The cooling affected the development of mountain landscapes, resulting in a change in the ratio of canopy-forming species, a shift in landscape belt boundaries, widespread development of sphagnum peatlands, and the emergence of northern species among peat-forming flora. At the end of the Little Ice Age, human settlement and active land use became the primary drivers of landscape transformation.