Paleoecological Conditions in the Steppe Zone of the Eastern European Plain at the Post-Catacomb Time

The article is devoted to reconstruction of paleoecological conditions of the steppe zone of the Eastern European Plain in the late Middle Bronze Age. The buried soils of the Kurgan of the Babinskaya culture in the Bogucharsky district of the Voronezh region were studied. It is shown that chemical properties of soil are determined by winter precipitation, while the state of its microbial community reflects the moisture content in the warm season. Annual precipitation trend in the steppe zone in the post-Catacomb period was reconstructed on the basis of findings of a comparative analysis of the chemical and biological properties of soils. It has been established that soils at the end of the 3rd millennium BC showed obvious signs of aridization, which led to a change in soils properties and types causing Southern Chernozems (rich black soils) formation in areas where Ordinary Chernozems is currently located. At the same time, microbial biomass in the buried soils significantly exceeded the current values, and the structure of soil microbial community was dominated by microorganisms involved in plant litter decomposition, which indicates favorable summer conditions and intense summertime precipitation. The research data do not relate to the crisis narrative regarding the paleoecological conditions of the late Middle Bronze Age in the steppe zone of the Eastern European Plain. Furthermore, results obtained do not support the idea of crisis as some kind of comprehensive complex of negative natural and social phenomena. It is more correct to speak of an asynchronous change in the annual course of moisture supply with a decrease in winter and an increase in summer precipitation against the background of general climatic cooling. The article raises the question of the specifics of global climate change manifestation and consequences in the steppe zone generally referred to the “4.2-ka BP aridification event”, which caused drought in the lower latitudes and an increase in precipitation in high latitudes while undergoning a general cooling trend. It is suggested that, under those conditions, climatic fluctuation scale in the steppe zone, located intermediately between the boreal and tropical belts, was not so high. Thus, the steppe remained attractive for communities which managed to adjust their economic model to new conditions.