Cultural Layers and Buried Soil of the Tula Kremlin (Russia) Tell About Palaeoenvironments and Landscape Transformation by Human Activity in the Late Middle Age

<p>Properties of the buried soil and cultural layers studied at the Tula Kremlin excavation (Central Russian Upland) allows us to carry out paleoenvironmental reconstruction of the stages of landscape transformation, characterize the early stages of human activity in this area, and also explain the location of a large cultural and economic center of the Late Middle Ages at a low hypsometric level in the immediate vicinity of the edge of the Upa River. The morphological and physicochemical characteristics of the cultural layers, buried and surface soils were studied, as well as micromorphological and micro biomorphic analyzes were carried out.</p><p>It is ascertained that the site where the fortress is located has never been flooded with a river. The buried soil developed on the mantle (loess-like) sediments is characterized by a typical profile for the surrounding watersheds. The signs of gleying (waterlogging) are weakly expressed or not expressed at all. Before the building of the fortifications, there was arable land or a kitchen garden on this site for a short time (5-7 years). In the cultural layers, due to the introduction of various building materials, there is an accumulation of substances and elements that are not characteristic of the surrounding soils. Pedogenic features preserved in the cultural layers made it possible to reconstruct the dynamics of paleoclimatic conditions in different periods of the Kremlin's construction or rebuilding. Cultural layer 1 (the 17-18^th centuries) was formed in relatively humid climatic conditions, and during the formation of cultural layer 2 (the 16-17^th centuries), it was slightly drier, but also colder. The soil buried under the cultural layers in the Kremlin at the beginning of the 16^th century is characterized by a dark-colored humus horizon and an almost absence of eluvial horizon with bleached sandy-silty material, which was especially clearly revealed when compared with the surface soil. If the paleosol is classified as Luvic Phaeozem (Anthric, Loamic, Aric), the surface soil &#8211; as Folic Retisol (Loamic, Cutanic). The paleosol developed during the warm time of the Medieval Climate Anomaly. This work was supported within the framework of Goszadanie no. 0191-2019-0046 and by RFBR, project N 19-29-05024 mk.</p>