Buried Arable Soils and Cultural Layers of Ancient Yaroslavl as a Record of Natural and Anthropogenic Processes

A comparative analysis of cultural layers (CLs) of different ages and buried arable horizons in the city of Yaroslavl was carried out in order to determine the contribution of climate change and stages of human existence to their properties and characteristics. A chronological series of three successive CLs dating back to 1150 AD (CL 3), the beginning of the 13th century (CL 2), and 1220–1238 AD (CL 1) reflects a climatic rhythm lasting for about a century and corresponding to the transition from the climatic optimum to the Little Ice Age in the Medieval Time. A chronological series of two arable soils includes soils plowed in the Early Iron Age (3rd–5th centuries AD) and in the Middle Ages (10th–11th centuries AD), i.e., the interval between them was about 700–900 years. The morphological, micromorphological, microbiomorphic, and basic chemical properties of soils and CLs have been analyzed. It is shown that the accumulative sedimentation processes of residential stages of territory development were influenced by natural and anthropogenic factors; and diagnostic indicators were preserved for both. Turbation processes characteristic of arable soils level out the reflection of climate dynamics in the soil properties while preserving the features characteristic of only the anthropogenic factor (for example, the application of certain fertilizers, irrigation, etc.).