Climatic and human impacts on landscape development of the Murav'ev Amursky Peninsula (Russian South Far East) in the Middle/Late Holocene and historical time

The Murav'ev-Amursky Peninsula is one of the most densely populated and industrially developed regions in the Russian Far East and is included in Bolshoy (Greater) Vladivostok. Before its intensive development began approximately 150 years ago, the mountainous portion of the peninsula was covered by coniferous forests, with mixed broadleaved forests confined to the coastal lowlands. Vegetation was notably transformed during industrial development. The landscape evolution and development of native communities under Middle/Late Holocene short-time climate changes are of particular interest. The results allow the relative importance of natural and anthropogenic factors in landscape transformation to be determined. Integrated studies of marine and terrestrial sequences on the Murav'inaya Bay coasts form the foundation for reconstructing changes in the Murav'ev-Amursky Peninsula landscapes over the last 5950 cal. Yrs. Pollen and diatom analyses as well as radiocarbon dating provide insight into the landscape response to climate fluctuations during the Middle/Late Holocene. Changes in the depositional environments were essentially controlled by fluctuations in the level of the Sea of Japan, as illustrated by the reconstructed history of Cherepashye Lake, which formed ∼2000 cal. Yr BP and replaced a lagoon. Several stages in this evolution show variations in the degree of connection with the sea. The materials obtained made it possible to reconstruct the environments at the time when site Cherepakha-13 came into being. The site appeared under climatic conditions similar to those of today, and the sea level was below the present sea level (Zaisanovskaya archeological culture). The people of the Lidovskaya and Yankovskaya archeological cultures settled under a climate warmer than that at present, with a sea level above the present-day sea level, and broadleaved forests with Korean pine grew on the coast. During the Yankovskaya and Krownovskaya cultural period, the climate began to cool and the sea level dropped. These changes led to deterioration of living conditions of these people. In the 13th century, when a Jurchen settlement appeared at Murav'inaya Bay, the coastal plain was dominated by Korean pine-broadleaved forests, and mixed forests were poorer in composition than the earlier forest vegetation. Additionally, alder woodlands became widespread around the lake. In the 17th to 19th centuries, coniferous tree species (and Korean pine in particular) abruptly gained in importance in the vegetation of the peninsula. Secondary oak forests became widely distributed in the 20th century due to intensive human activities.