Holocene environmental change in southwestern Crimea (Ukraine) in pollen and soil records

Abstract

Pollen records and soil development sequences from the Heraklean Peninsula and the Chyornaya Valley provide information on climatic change and fluctuation of ecological boundaries (mesic forests, steppes and sub-Mediterranean shrublands) in southwestern Crimea during the Holocene. Forests of Quercus, Ulmus, Corylus and Carpinus existed in the Heraklean Peninsula between 12 ka and 11 ka. The subsequent reduction of arboreal pollen and the expansion of Artemisia and Knautia, in conjunction with chernozem soil development, indicate prevailing steppe conditions between 11 ka and 7.5 ka. An increase in arboreal pollen, dominated by sub-Mediterranean and Mediterranean taxa, and the development of brown cinnamonic (calfersic) soil suggest higher temperatures and summer drought between 7.5 ka and 5 ka. An increase in arboreal pollen and the development of a meadow cinnamonic soil suggest an increase in moisture between 5.4 ka and 4.6 ka. A subsequent decrease in AP and the development of calcic horizons in cinnamonic soils indicate that a dry phase occurred between 4.2 ka and 3.5 ka. Woodland expansion occurred again after 3.2 ka, only to be interrupted by the establishment of Greek farms in the fifth century BC. An increase in AP on or after the first century BC was the result of climatic amelioration in conjunction with farm abandonment prompted by political crisis and steppe warrior raids. Although Holocene pollen and soil records from the Ukrainian steppes present climate trends similar to the Heraklean Peninsula, differences in plant taxa and soil response to climatic changes exist due to their different position with respect to marine influences.