Damming Weakens the Groundwater and Surface Water Exchange and Its Nitrate Removal in Semi-arid Prairie Rivers

Surface water (SW)-Groundwater (GW) exchange plays a vital role in a prairie aquatic system and the biogeochemical cycling in such a system. Considering the inadequate understanding of damming on SW-GW exchange, a damming prairie river in Southeast Eurasian steppe was chosen to investigate variations of the SW-GW exchange and its influences on the fate of nitrate (NO3-). Both hydraulic and hydrochemical methods were applied to precisely depict the daily and seasonal exchange processes. The upstream and downstream reaches of the dam were observed to be upwelling and downwelling conditions respectively within a hydrologic year. Results obtained from multiple tracer methods and hydraulic method indicate that damming contributed to transfer the stream from the upwelling to the downwelling condition and weaken the SW-GW exchange in the downstream. The patterns of SW-GW exchange modulated the NO3- uptake or production between the SW and the GW. NO3- was mainly removed in the SW-GW exchange zone (SW-GW EZ) of the upwelling segment, while produced in the downwelling segment. Both the removal and production of NO3- were enhanced during snowmelt period, which might be an active period for the SW-GW exchange and NO3- fate. This study underscores the negative effect of damming on the SW-GW exchange and accompanied NO3- removal in prairie river systems.

Budzhak Population: an experience of a fugitive review of 18th-century observations

Budzhak (in modern Moldova and Ukraine) is the western part of the Eurasian steppe, the natural character of which had determined the ways of the local life for centuries. The Ottoman and the Russian Empires had clashed here in the eighteenth century, on the eve of the European Enlightenment. This fight was to determine further prospects for development, while many contemporaries and eyewitnesses tried to guess any signs of these prospects. A profound social crisis in south-eastern Europe contributed to political and ethnic and confessional changes and was changing the natural landscape. The Turkic Muslim population had to leave these lands under the growing pressure of these changes, and the new population was predominantly Christian. Now the Christians determined the way of life in Budzhak, even its flora and fauna.

Fantastic Fauna in a Global Perspective: understanding composites in early Eurasian Antiquity

Ancient tombs and hoards across the Eurasian steppe call for a thorough revision of art-historical categories associated with pastoral societies from Mongolia to Crimea. This study focuses on one such category. “Animal style” is an umbrella term traditionally used to categorise portable precious metalwork ornamented with dynamic scenes of vigorous animal fights and entwined zoomorphic designs. With its emphasis on irregular animal anatomies and deeply rooted in a “pars-pro-toto” mode of expression, steppe imagery of fantastic fauna presents a useful case study in broader investigations of composites in the ancient world and their diffusion across cultural spheres. This study views beasts through a binary lens, the structured monsters of Greco-Roman thinkers and the organic composites of nomadic steppe artisans. In the Western canon, “composites” existed within a politically-manufactured framework of governable “otherness”, in which fantastic fauna conveys a certain tension with the exotic, unknown and uncontrollable East. Meanwhile, in the visual rhetoric of steppe artisans, monsters represented a tension with the (cyclical) shifts occurring in one's biota rather than the tumultuous events in one's constructed environment. This paper explores how the contrasting steppe pastoralist and sedentary imperial world-views came to define the various functions and meanings of “composites” in Eurasian Antiquity.

Anthropogenic disturbances consistently favor the high-yield strategists of soil bacterial community in the Eurasian steppe

Purpose Multiple anthropogenic disturbances, such as climate warming and nitrogen deposition are affecting terrestrial ecosystems. Different disturbances may have some consistent effects on the soil microbial community, which remains largely unexplored. Methods We mimicked 16 anthropogenic disturbances in a steppe ecosystem, and measured the absolute abundance and taxonomic composition of soil bacterial communities with qPCR and amplicon sequencing, respectively. Results We found that while the absolute abundance of each of the four dominant bacterial phyla did not show a consistent response to these disturbances, that of the five subdominant phyla showed a consistent increase. Meanwhile, these disturbances consistently stimulated the relative abundances of metabolic functions for high-growth-yield, including the transport/metabolism of amino acids and carbohydrates. Stochastic processes (e.g., random birth) played more critical roles in structuring the subdominant than dominant phyla, and the disturbances promoted the stochastic processes. Conclusions Overall, the high-yield traits and stochasticity of subdominant phyla led to their positive responses to disturbances. Furthermore, our findings indicate that the intensifying human activities are likely to cause a high-yield-strategies-toward shift in soil microbial composition in the Eurasian steppe ecosystem.

Nomads in the Middle East

A history of pastoral nomads in the Islamic Middle East from the rise of Islam, through the middle periods when Mongols and Turks ruled most of the region, to the decline of nomadism in the twentieth century. Offering a vivid insight into the impact of nomads on the politics, culture, and ideology of the region, Beatrice Forbes Manz examines and challenges existing perceptions of these nomads, including the popular cyclical model of nomad-settled interaction developed by Ibn Khaldun. Looking at both the Arab Bedouin and the nomads from the Eurasian steppe, Manz demonstrates the significance of Bedouin and Turco-Mongolian contributions to cultural production and political ideology in the Middle East, and shows the central role played by pastoral nomads in war, trade, and state-building throughout history. Nomads provided horses and soldiers for war, the livestock and guidance which made long-distance trade possible, and animal products to provision the region's growing cities.

Exotica, Fashion and Immortality: The New Use of Gold in Han Dynasty China (206 bce–ce 220)

This article explores the use of gold in the elite tombs of Han dynasty China, the popular use of which originated outside the Chinese cultural milieu, and its integration into the Han portfolio of materials representing people's expectations for the afterlife, such as immortality and well-being. In contrast to jade, which had a long history of use in China, gold was in itself a ‘new’ element of Chinese culture. This article outlines the introduction of gold objects from Europe and Central Asia via the Eurasian Steppe and borderland of China from around the eighth century bce. The unprecedented use of gold in the Han-specific jade suits, and the process by which foreign types of zoomorphic motifs were adopted and connected with local motifs, are explored. In light of the political change from multiple competing states before the first unification in Chinese history in the third century bce, and the development in ideology and concept of an ideal and eternal afterlife, this article explains the reasons and meanings of the new use of gold in Han dynasty China and the composite system of motifs, materials and objects.

TRACES OF THE ANCIENT PATHS IN THE STEPPE TAVRIA

The original appearance of the steppe surface of the southern part of the eastern European plane was transformed by the centuries of the anthropogenic impact. Along with feather grass the traces of the ancient roads have disappeared. However, the satellite images still detect the areas around some kurhans having kept the waggons traces. We can recognize them due to the different color of vegetation as well as by the coloration of the open soil. The antiquity of the roads near kurhans is witnessed by the cases of tracks, covered by the burial mounds, that were erected in the Bronze Age. An additional indicator of the ancient transport network on the maps of the 19th century are wells or groups of pits in the open steppe, the number of which should be associated with the need to water a large number of cattle. The latter occurred during the arrival of a trade caravan or a train of wagons. The kurhans themselves are an ancient form of mass cult buildings in the Eurasian steppe, which have attracted both large main and secondary roads. Powerful tradition of building kurhans, fading and restoring through times, existed from the Eneolithic to the late Middle Ages. The appearance of new mounds or the completion of existing ones periodically renewed the system of landmarks in the monotonous steppe. The paper provides an overview of previously unknown megastructures near the Scythian giant kurhans of Oguz and Chortomlyk, which in the form of light parallel stripes are recorded on satellite images. These stripes are probably traces of trenches or the foot of stone alleys, that were found to the east of the edge of the Oguz and outreached 800—850 m, and from Chortomlyk — 670 m. A search on various satellite images of the similar light stripes near other kurhans did not yield positive results. However, in the central part of the Dnieper-Molocha steppe region, satellite images luckily detected 19 nodes (intersections) of ancient ways connected to the kurhans’ mounds. Some of these nodes do yet not fit the complete road network of the region. But six of these nodes appear to be in the area of the route of the ancient path, known in the Middle Ages as Muravsky (Murava Route). It leaded from the Don basin, through the left (eastern) part of the basin of the Dnipro River to Crimea through the Isthmus of Perekop. Interestingly, this branch of the Muravsky Trail crosses the Sirogozy ravine between the kurhans of Kozel and Oguz. In previous reconstructions of the transport network, the option of passing this branch in the south of the Oguz, between the giant embankment and Diyiv kurhan, was preferred. The other three intersections lie in the lane of the old Chumaks’ Way or the Crimean Way, marking a forty-kilometer section between kurhans Kozel and Velyka Tsymbalka. From the center of the Tavria Steppe at least four directions of paths emerge towards the ancient Dnipro fords-crossings: Rogachytsia, Lepetych, Cair (Nosakiv) and Kіzikermen (Tavan).

Modern Siberian dog ancestry was shaped by several thousand years of Eurasian-wide trade and human dispersal

Dogs have been essential to life in the Siberian Arctic for over 9,500 y, and this tight link between people and dogs continues in Siberian communities. Although Arctic Siberian groups such as the Nenets received limited gene flow from neighboring groups, archaeological evidence suggests that metallurgy and new subsistence strategies emerged in Northwest Siberia around 2,000 y ago. It is unclear if the Siberian Arctic dog population was as continuous as the people of the region or if instead admixture occurred, possibly in relation to the influx of material culture from other parts of Eurasia. To address this question, we sequenced and analyzed the genomes of 20 ancient and historical Siberian and Eurasian Steppe dogs. Our analyses indicate that while Siberian dogs were genetically homogenous between 9,500 to 7,000 y ago, later introduction of dogs from the Eurasian Steppe and Europe led to substantial admixture. This is clearly the case in the Iamal-Nenets region (Northwestern Siberia) where dogs from the Iron Age period (∼2,000 y ago) possess substantially less ancestry related to European and Steppe dogs than dogs from the medieval period (∼1,000 y ago). Combined with findings of nonlocal materials recovered from these archaeological sites, including glass beads and metal items, these results indicate that Northwest Siberian communities were connected to a larger trade network through which they acquired genetically distinctive dogs from other regions. These exchanges were part of a series of major societal changes, including the rise of large-scale reindeer pastoralism ∼800 y ago.

Dairying enabled Early Bronze Age Yamnaya steppe expansions

During the Early Bronze Age, populations of the western Eurasian steppe expanded across an immense area of northern Eurasia. Combined archaeological and genetic evidence supports widespread Early Bronze Age population movements out of the Pontic–Caspian steppe that resulted in gene flow across vast distances, linking populations of Yamnaya pastoralists in Scandinavia with pastoral populations (known as the Afanasievo) far to the east in the Altai Mountains1,2 and Mongolia3. Although some models hold that this expansion was the outcome of a newly mobile pastoral economy characterized by horse traction, bulk wagon transport4–6 and regular dietary dependence on meat and milk5, hard evidence for these economic features has not been found. Here we draw on proteomic analysis of dental calculus from individuals from the western Eurasian steppe to demonstrate a major transition in dairying at the start of the Bronze Age. The rapid onset of ubiquitous dairying at a point in time when steppe populations are known to have begun dispersing offers critical insight into a key catalyst of steppe mobility. The identification of horse milk proteins also indicates horse domestication by the Early Bronze Age, which provides support for its role in steppe dispersals. Our results point to a potential epicentre for horse domestication in the Pontic–Caspian steppe by the third millennium bc, and offer strong support for the notion that the novel exploitation of secondary animal products was a key driver of the expansions of Eurasian steppe pastoralists by the Early Bronze Age.