Еnvironmental conditions in the transition period between the Bronze and the Iron Age in the Ishim river basin, Western Siberia (according to the on-site paleobotanical data from the settlement of Marai 1)

The paper focuses on the new archaeobotanical data of the environment near the hillfort of Marai 1 and on evaluation of their role in the paleoeconomical changes in the forest-steppe area in the transition period from the Bronze to the Iron Age. Archaeological materials of the cultural layers characterize various paleoeconomic models which existed in the same landscape niche with a four-century interval. We compared the bottom and the roof level of semi-dugouts by the composition of archaeobotanical macro-remains of two habitation phase: the transition period from the Bronze Age to the Iron Age (IX — the beginning of the VIII century BC), and the Early Iron Age (IV–III century BC). Plant macro analysis revealed that the village was surrounded by grass and forbs meadows during the first and the second occupation phases, the local living environment did not change significantly. The economic activity was more intensive in the early Iron Age, which caused an increase in the proportion of weeds near the dwellings. Not many coastal and aquatic plants were discovered at the roof level, which is indicative that the roof was covered the sod, and cane or reed sheaves were not used. The analysis of saturation with fish bones of the cultural layer into dwellings floor showed equal results for both habitation periods. Basing on pollen and spore data of the cultural layers, we can say that the settlement was surrounded by open forest-steppe landscapes during two occupation phases. Meadow and steppe were the main vegetation background, with a significant share of wet meadows in the flood plain. There were only small birch forests in the immediate vicinity of the settlement in the transition period between the Bronze and the Early Iron Age, but the share of forests near the hillford of Marai 1 began to increase in the Early Iron Age. In general, the reconstruction of local environmental conditions near Marai 1 in the transition period between the Bronze and the Early Iron Ages did not show any signs of an ecological crisis or significant changes in the appearance of landscapes which could cause a return to an appropriating economy. Therefore, reorientation to hunt elk and roe was not synchronized with a widespread appearance of forest along the Ishim River valley. The economy specificity of population of the Krasnoozersk culture, formed as a synthesis among the local pastoralists and groups of taiga fishermen and hunters who came from the North, was not so much determined by natural conditions as by the influence of the newcomers. Later, in the Early Iron Age, there was indeed a slight increase in the proportion of forests in the immediate vicinity of Marai 1 settlement, despite this, livestock breeding was a basis of the hillforts' economy. Fish was unambiguously one of the important components in the diet of the population during both habitation phases, regardless of the basic economic orientation. Thus, there is no reasonable basis yet for indicating that a serious climatic cataclysm dramatically changed the habitat of the population of the Ishim River basin at the boundary between the Bronze and the Early Iron Age