Der Mensch als landschaftsprägender Faktor des westlichen Bodenseegebietes seit dem späten Atlantikum

Eingebunden in ein längerfristiges archäologisches Projekt zur jungsteinzeitlichen und bronzezeitlichen Besiedlungsgeschichte im Alpenvorland tragen archäobotanische Untersuchungen zur Kenntnis der Wechselwirkung Mensch — Landschaft in dieser Zeit bei. Pollenanalysen in Toteislöchern und in der Flachwasserzone des Bodensees sowie Großrestanalysen an den Kulturschichten praehistorischer Feuchtbodensiedlungen geben Hinweise darauf, daß bereits ab dem späten Atlantikum ein enger Zusammenhang zwischen menschlicher Besiedlung und Wirtschaft und der Veränderung terrestrischer und limnischer Ökosysteme bestand.researc

Neue Forschungen zur Umwelt und Ernährung der Pfahlbaubewohner aus Südwestdeutschland

Von 1983 bis 1993 wurden im Rahmen des DFG-Schwerpunktprogramms „Siedlungsarchäologische Untersuchungen im Alpenvorland“ spätneolithische und bronzezeitliche Ufersiedlungen am westlichen Bodensee untersucht. Botanische Untersuchungen an den archäologischen Fundplätzen und Pollenprofile aus nahegelegenen Seen und Mooren ergaben große Unterschiede zwischen spätneolithischer und bronzezeitlicher Landnutzung. Das Landnutzungsmodell für das Spätneolithikum, ein Wald-Feldbau-Verfahren mit Feuereinsatz, wird seit 1994 experimentell überprüft. Darüber hinaus wurde 2003 ein neues Projekt begonnen, in dem mehr und bessere Daten zur spätneolithischen und bronzezeitlichen Landnutzung erhoben werden sollen. Das Untersuchungsgebiet ist das Südufer des Überlinger Sees mit mehr als zwölf prähistorischen Ufersiedlungen. An diesem Seeufer und auf dem südlich anschließenden Bodanrück wurden fünf Pollenprofile entnommen. Die vorläufigen Ergebnisse bestätigen die Resultate vom Untersee und aus dem Hegau.In the years 1983-93, the „Schwerpunktprogramm der Deutschen Forschungsgemeinschaft ‚Siedlungsarchäologische Untersuchungen im Alpenvorland’“ studied Late neolithic and Bronze Age lake shore dwellings in the western Lake Constance region. Botanical investigations at the sites and of long-term sediment and peat profiles nearby reveal big differences between Late Neolithic and Bronze Age land use. The favoured land-use model for the Late Neolithic, a slash-and-burn system with shifting cultivation, was tested experimentally since 1994. In 2003, a new project was initiated to collect consistent environmental data about Late Neolithic and Bronze Age land use. As research area the southern shore of the Überlinger See with more than twelve Neolithic and Bronze Age lake shore dwellings was choosen. Five sites at this shore and at the adjacent Bodanrück were sampled for – offsite – pollen analysis. The preliminary pollen results seem to confirm the pollen data from the Untersee and Hegau region

Zafar, Capital of Himyar, Sixth Preliminary Report, February–March 2006

Die Grabungsmannschaft der Universität Heidelberg untersucht Zafar – Hauptstadt der himyarischen Stammeskonföderation – seit 1998. Dieses interdisziplinäre Projekt erbrachte Funde in der Kunstgeschichte, Botanik und Chronologi

Paysages, productions et collectes végétales en Limousin (Massif central occidental) de la Tène finale à la fin du Moyen Âge (100 BC-1 400AD)

Entre 1996 et 2004, plusieurs sites archéologiques du Limousin ont fait l’objet d’une analyse carpologique. Bien que le nombre de sites et de structures analysés soit modeste, près de 219     000 restes carbonisés, imbibés ou minéralisés et environ 300 taxons de plantes cultivées et sauvages ont été déterminés permettant l’élaboration d’une première synthèse pour une période allant de la Tène finale au bas Moyen Âge. Ce travail intègre également la publication de plusieurs études carpologiques de nécropoles gallo-romaines ainsi que les acquis régionaux des recherches anthracologiques, palynologiques et sédimentologiques. La synthèse sur les plantes cultivées et utilitaires met en évidence une modification des productions céréalières entre la fin de l’époque gallo-romaine et le haut Moyen Âge, caractérisée par la montée en puissance du seigle (Secale cereale). Elle rend compte aussi d’un développement de l’arboriculture à partir de l’époque gallo-romaine, puis au haut Moyen Âge, notamment en contexte urbain. Des importations ont également été mises en évidence, comme le poivre (Piper nigrum) au haut-Empire.Between 1996 and 2004 palaeobotanical studies were performed in archaeological sites of Limousin. Despite the limited number of the sites and structures studied, the richness in plant macroremains and taxa strenghthened by the use of additional palaeobotanical studies as well as anthracological, palynological, sedimentological and palaeoclimatic data allows to propose a first synthesis concerning the agricultural production between the end of La Tene and the low Middle Ages. More than 219.000 remains (carbonized, waterlogged and mineralized) and circa 300 wild and cultivated plants taxa were determined. This work emphasizes a change in the cereal production between the end of the Gallo-Roman period and the High Middle Age characterized by the increase in rye (Secale cereale) cultivation. It also shows the development of arboriculture during the Gallo-Roman period and the high Middle Ages, especially in urban area. The import of an exotic spice : pepper (Piper nigrum), is demonstrated during the High Empire

Akkumulation von amorphem Silizium in holozänen Seesedimenten des Herrenwieser Sees (Nordschwarzwald)

Datierte Seesedimente sind Geoarchive, welche klimagesteuerte biogeochemische Prozesse im Einzugsgebiet aber auch gewässerinterne Prozesse widerspiegeln. Im Rahmen des DFG-PAK 179 analysierten wir in datierten Sedimentkernen des Herrenwieser Sees (Nordschwarzwald) verschiedene Si-Fraktionen und Gehalte weiterer Elemente, um daraus Aussagen über die längerfristige Elementdynamik in den Böden des Einzugsgebiets abzuleiten. Das mit Hilfe von heißer NaOH aufschließbare amorphe („biogene“) Silizium, welches v.a. die Diatomeen-Produktion eines Sees widerspiegelt (vgl. Conley, 1998; Sauer et al., 2006), ist eng gekoppelt an die Klimaschwankungen während des Holozäns. Vor allem im feucht-warmen Atlantikum (HTM-Holocene-Thermal-Maximum) weisen die Bioproduktion im untersuchten See und damit das Kieselalgenwachstum die höchsten Gehalte auf

Intensification of agriculture in southwestern Germany between the Bronze Age and Medieval period, based on archaeobotanical data from Baden-Württemberg

A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern Germany since the Bronze Age. It involved fallow periods, where the arable land is left without crops in order to let it recover its fertility for several years while becoming grassland. This led to regeneration of the topsoil humus, which could later be mobilized by cultivation. With later farming systems, the supply of nutrients needed for crops could also be provided by manuring, which allowed shorter fallow periods but required the production of manure. Such cultivation systems with short or even without fallow phases and with intensive manuring are known from the medieval period as one, two or three field systems of agriculture and their development was an important step towards the intensification of farming. The current study considers on-site plant macrofossil data from archaeological sites as well as the off-site pollen data from cores in Baden-Württemberg in order to recognize the main changes towards agricultural intensification through time from the Bronze Age up to medieval times. The various landscape types included in the study area also reveal their different agricultural histories of intensification. In lowlands with good soils, the intensification can be recognized earlier and more strongly than in uplands or other marginal areas. The main shift towards intensification took place in the Roman period, which is also confirmed by written sources of the time that mention manuring as well as a kind of two field system and alternation between grassland and arable land.publishedVersio

Prediction of Holocene Mercury Accumulation Trends by Combining Palynological and Geochemical Records of Lake Sediments (Black Forest, Germany)

Forest vegetation plays a key role in the cycling of mercury (Hg) and organic matter (OM) in terrestrial ecosystems. Litterfall has been indicated as the major transport vector of atmospheric Hg to forest soils, which is eventually transported and stored in the sediments of forest lakes. Hence, it is important to understand how changes in forest vegetation affect Hg in soil and its biogeochemical cycling in lake systems. We investigated the pollen records and the geochemical compositions of sediments from two lakes (Schurmsee and Glaswaldsee) in the Black Forest (Germany) to evaluate whether long-term shifts in forest vegetation induced by climate or land use influenced Hg accumulation in the lakes. We were particularly interested to determine whether coniferous forests were associated with a larger export of Hg to aquatic systems than deciduous forests. Principal components analysis followed by principal component regression enabled us to describe the evolution of the weight of the latent processes determining the accumulation of Hg over time. Our results emphasize that the in-lake uptake of Hg during warm climate periods, soil erosion after deforestation and emissions from mining and other human activities triggered changes in Hg accumulation during the Holocene stronger than the changes caused by forest vegetation alone

Late Neolithic Agriculture in Temperate Europe — A Long-Term Experimental Approach

Long-term slash-and-burn experiments, when compared with intensive tillage without manuring, resulted in a huge data set relating to potential crop yields, depending on soil quality, crop type, and agricultural measures. Cultivation without manuring or fallow phases did not produce satisfying yields, and mono-season cropping on freshly cleared and burned plots resulted in rather high yields, comparable to those produced during modern industrial agriculture - at least ten-fold the ones estimated for the medieval period. Continuous cultivation on the same plot, using imported wood from adjacent areas as fuel, causes decreasing yields over several years. The high yield of the first harvest of a slash-and-burn agriculture is caused by nutrient input through the ash produced and mobilization from the organic matter of the topsoil, due to high soil temperatures during the burning process and higher topsoil temperatures due to the soil’s black surface. The harvested crops are pure, without contamination of any weeds. Considering the amount of work required to fight weeds without burning, the slash-and-burn technique yields much better results than any other tested agricultural approach. Therefore, in dense woodland, without optimal soils and climate, slash-and-burn agriculture seems to be the best, if not the only, feasible method to start agriculture, for example, during the Late Neolithic, when agriculture expanded from the loess belt into landscapes less suitable for agriculture. Extensive and cultivation with manuring is more practical in an already-open landscape and with a denser population, but its efficiency in terms of the ratio of the manpower input to food output, is worse. Slash-and-burn agriculture is not only a phenomenon of temperate European agriculture during the Neolithic, but played a major role in land-use in forested regions worldwide, creating anthromes on a huge spatial scale.© 2017 the authorspublishedVersio

Historical Spruce Abundance in Central Europe: A Combined Dendrochronological and Palynological Approach

Spruce is the most cultivated tree species in modern forestry in Central Europe, since it has the ability to grow on many soil types with profitable biomass accumulation. However, even-aged and uniform spruce forests are affected by recurring droughts and associated biotic stressors leading to large-scale diebacks across Central Europe causing controversies among foresters and nature conservationists. We investigate the role of spruce in historical woodlands by using 15666 spruce timbers from historical buildings and on the basis of pollen-based land cover estimates using the REVEALS model from 157 pollen sites in southern Central Europe. Start and end dates of the spruce timber samples and their dendrological characteristics (age, growth rates and stem diameters) were used to obtain information on past forest structures. Tree rings and REVEALS estimates are combined at a spatial scale of 1° × 1° resolution, grouped in four sub-regions, and a temporal resolution of 100-year time windows starting from 1150 to 1850 CE. We found that spruce dominates the species assemblage of construction timber with almost 41% and that the harvest age varies little through time, whereas a declining trend in growth rates and stem diameters are observed toward times before modern forestry. Temporal and regional differences in spruce abundance and building activity were found highlighting periods of (i) land abandonment and forest expansion in the 14th century, (ii) increased wood consumption during the 16th century due to population increase and beginning industrial developments, (iii) a forest recovery during and after the Thirty years' war, and (iv) afforestation efforts from the 1650s onwards. Furthermore, this study shows that spruce was constantly present in the study area in most studied sub-regions for the last 800 years. We demonstrate the need of combining tree-ring and pollen data to identify spatiotemporal patterns in spruce abundance and utilization.publishedVersio

The potential of stomata analysis in conifers to estimate presence of conifer trees: examples from the Alps

To estimate whether or not a plant taxon found in the fossil record was locally present may be difficult if only pollen is analyzed. Plant macrofossils, in contrast, provide a clear indication of a taxon's local presence, although in some lake sediments or peats, macrofossils may be rare or degraded. For conifers, the stomata found on pollen slides are derived from needles and thus provide a valuable proxy for local presence and they can be identified to genus level. From previously published studies, a transect across the Alps based on 13 sites is presented. For basal samples in sandy silt above the till with high pollen values of Pinus, for example, we may distinguish pine pollen from distant sources (samples with no stomata), from reworked pollen (samples with stomata present). The first apparent local presence of most conifer genera based on stomata often but not always occurs together with the phase of rapid pollen increase (rational limit). An exception is Larix, with its annual deposition of needles and heavy poorly dispersed pollen, for it often shows the first stomata earlier, at the empirical pollen limit. The decline and potential local extinction of a conifer can sometimes be shown in the stomata record. The decline may have been caused by climatic change, competition, or human impact. In situations where conifers form the timberline, the stomata record may indicate timberline fluctuations. In the discussion of immigration or migration of taxa we advocate the use of the cautious term "apparent local presence” to include some uncertainties. Absence of a taxon is impossible to prove