Astrid Stobbe

Late-Holocene land-use history and environmental changes at the high altitudes of St Antönien (Switzerland, Northern Alps): Combined evidence from pollen, soil and tree-ring analyses

In climatically sensitive regions such as the Northern Alps, changes in climate and land use have a strong impact on landscapes, vegetation, animals and humans. Multidisciplinary investigations in the high St Antönien Valley (Switzerland) at 1400—3000 m a.s.l. have generated a reconstruction of land-use history. Humans began affecting the landscape of this high mountain region during the Bronze Age. Multiproxy palaeoenvironmental studies show that the present cultural landscape of the valley has been the result of long-term human environmental interactions. Pollen, soil and tree analyses were combined with archaeological and historical archives to provide strong evidence of the complexity of the high-mountain land-use system over the last 3500 years. Phases of agro-pastoral activity from Bronze Age (around 1300 BC), Iron Age (800—15 BC), Roman Period (15 BC—AD 450) and Middle Ages (AD 450—1500) are linked to climate and economic, social and cultural developments. Our results reveal that expansions of pasture land, in combination with climatic fluctuations, led to pronounced ecological changes in St Antönien Valley. Humans adjusted land-use practices according to changing environmental conditions. In this context, the use of fire was an important factor in land management. Forest clearances reached maximum intensity during the late Middle Ages (AD 1300—1500) and triggered natural catastrophes that were amplified during the most severe environmental phase (AD 1600—1850) of the ‘Little Ice Age’ (LIA).

Asynchronous Holocene colluvial and alluvial aggradation: A matter of hydrosedimentary connectivity

Based on Optically Stimulated Luminescence (OSL) and radiocarbon dating we establish chronologies of colluviation and alluviation in different floodplain sections of the northwestern Wetterau loess basin (Germany). Similar to some other European valley floors, Holocene floodplain aggradation is marked by two important breaks: (1) a millennial-scale delay between the Neolithic agricultural colluviation and floodplain aggradation. In loess catchments agricultural colluviation started at about 7000 cal. BP and anthropogenic floodplain aggradation only at about 2200 ± 200 cal. BP; (2) a centennial-scale variability in a temporary rise in rates of anthropogenic floodplain aggradation (up to 3.6 ± 1.7 mm/yr) during the High Middle Ages in directly neighbouring reaches. Independent archaeologic, historic, and vegetation records document distinct agricultural histories of hillsides and floodplains and highlight the importance of hydrosedimentary connectivity as compared with land use intensity. The late Iron Age start of alluviation can be linked to the introduction of an integrated land use system with intense cultivation on hillsides and immediate neighbouring floodplains. The centennial-scale variability of medieval peak aggradation is a result of the successive introduction (or temporal failure) of hydraulic water milling infrastructure. Using palaeoecological and geomorphological information for reconstructing cause and consequence of sediment redistribution in coupled human–natural systems requires firm information about the spatial organisation and technological abilities that are associated with socio-agricultural transformations.

Archaeobotanical analysis of plant use at Kamennyi Ambar, a Bronze Age fortified settlement of the Sintashta culture in the southern Trans-Urals steppe, Russia

This paper presents the results of plant macro-remain and charcoal analyses from a fortified settlement of the Sintashta archaeological culture in the southern Trans-Urals, Russia. The work was carried out within the scope of a German/Russian research project and represents the first systematic studies on Bronze Age plant material in the region. Previous archaeological and archaeozoological investigations have revealed that the Sintashta economy was mainly based on livestock herding of cattle, small cattle and horses. There is additional evidence for fishing as well as some copper metallurgy, while the role of agriculture is still being discussed. Archaeobotanical studies therefore focused on the question whether the Bronze Age settlers cultivated, processed or stored crop plants. All cultural layers and important settlement features were systematically sampled, wet-sieved and subjected to plant macro-remain analysis. Anthracological (charcoal) samples were taken from burnt structures and charcoal concentrations. As no evidence for either cultivated plants or agricultural practices was found in the settlement, it can be concluded that farming was not practised at Kamennyi Ambar, and that the Sintashta economy was exclusively based on animal husbandry and fishing in that steppe region. The charred plant remains found in the settlement represent a broad spectrum of wild plants which can be attributed to vegetation units like small woodlands, steppe, ruderal steppe, meadow steppe and the riparian zone. As supported by palynological studies, Bronze Age vegetation patterns are largely comparable with those of the modern steppe environment. Since some of the recorded taxa have the potential to serve as food, fodder or for craft purposes, the use of wild plants at Kamennyi Ambar must be considered. The charcoal analysis reveals the dominance of Pinus sylvestris and Betula sp., representing a typical tree taxa spectrum from the steppe region during the Bronze Age as well as present times. It can be concluded that wood was readily available for construction material and fuel.

Bronze Age human–landscape interactions in the southern Transural steppe, Russia – Evidence from high-resolution palaeobotanical studies

The Transural steppe is a cultural contact zone between areas east and west of the Ural Mountains. Mobile pastoralism is the traditional way of life in the steppe, while sedentary cultures constitute an exception, probably as a result of climatic variations. A change of lifestyle together with other innovations is documented at the turn of the 3rd to the 2nd millennia BC and often believed to have been accompanied by a shift to agro-pastoralism. To examine the ecology and economy in the Bronze Age steppe, we employed a combination of methods. As proxy-data, plant macro-remains from archaeological excavations of Sintashta fortified settlements and pollen from off-site archives were used for a high-resolution palaeoenvironmental reconstruction. Statistical comparisons of past and present pollen spectra show no significant differences in vegetation distribution. This allowed us to map the recent vegetation units by multispectral satellite imagery and to use them for modelling. Models further incorporate steppe productivity, carrying capacity and population figures to estimate herd sizes. Even if the climate was suitable for agriculture, evidence is missing from all botanical records. The economic mainstay was animal husbandry. Models consider autonomous activity zones of at least 4 km radius surrounding each Sintashta settlement where grazing resources could easily sustain the estimated population and their livestock. The river is seen as the determining factor to settle in this region as it provided constant access to water and valuable natural grazing areas. During dry years and winter, the productive meadow steppes functioned as reserve pastures.