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Giesecke T.,University of Gottingen | Bennett K.D.,Queen's University of Belfast | Bennett K.D.,Uppsala University | Birks H.J.B.,University of Bergen | And 13 more authors.
Quaternary Science Reviews | Year: 2011

Mid to high latitude forest ecosystems have undergone several major compositional changes during the Holocene. The temporal and spatial patterns of these vegetation changes hold potential information to their causes and triggers. Here we test the hypothesis that the timing of vegetation change was synchronous on a sub-continental scale, which implies a common trigger or a step-like change in climate parameters. Pollen diagrams from selected European regions were statistically divided into assemblage zones and the temporal pattern of the zone boundaries analysed. The results show that the temporal pattern of vegetation change was significantly different from random. Times of change cluster around 8.2, 4.8, 3.7, and 1.2 ka, while times of higher than average stability were found around 2.1 and 5.1 ka. Compositional changes linked to the expansion of Corylus avellana and Alnus glutinosa centre around 10.6 and 9.5 ka, respectively. A climatic trigger initiating these changes may have occurred 0.5 to 1 ka earlier, respectively. The synchronous expansion of C. avellana and A. glutinosa exemplify that dispersal is not necessarily followed by population expansion. The partly synchronous, partly random expansion of A. glutinosa in adjacent European regions exemplifies that sudden synchronous population expansions are not species specific traits but vary regionally. © 2011 Elsevier Ltd.

Ehrmann O.,Munster 12 | Biester H.,TU Braunschweig | Bogenrieder A.,Albert Ludwigs University of Freiburg | Rosch M.,Landesamt fur Denkmalpflege im Regierungsprasidium Stuttgart
Vegetation History and Archaeobotany | Year: 2014

Experimental research into Neolithic agriculture has been underway in Forchtenberg, southwest Germany, since 1998. The experimental area is a medium age mixed-deciduous forest featuring different soils, mainly haplic and stagnic luvisols. In this experimental setting, research has focussed on comparisons of soil nutrients and crop yields resulting from slash and burn cultivation and from cultivation with hoeing. We show that slash and burn produces significantly higher yields, although always depending on soil quality. Hoe tilling is only profitable on the best soils in the first year after clearance. Continuous cultivation with hoeing produces too low yields, but repeated annual cultivation on slash and burn sites also resulted in progressively lower yields due to decreasing levels of nitrogen in the soil. Nitrogen originates not from burned wood but from the burning and mineralisation of organic matter in the topsoil. After burning and cultivation, a break of about 10-15 years is necessary, not only for forest re-growth, but also for the regeneration of the top soil and its nitrogen content. Slash and burn agriculture is therefore an easy and reliable tool for food production by a small population living in a large forested area. © 2014 Springer-Verlag Berlin Heidelberg.

Rosch M.,Landesamt fur Denkmalpflege im Regierungsprasidium Stuttgart | Kleinmann A.,Ritter Eccard Str. 5 | Lechterbeck J.,Landesamt fur Denkmalpflege im Regierungsprasidium Stuttgart | Wick L.,University of Basel
Vegetation History and Archaeobotany | Year: 2014

Off-site pollen data as well as onsite plant macrofossil data from Southwest Germany enable the distinguishing of three main phases of agricultural land use history. The last phase, here simplified called the "Extensive ard phase", had already started in the Bronze Age and ends in the 19th century a.d. It is characterized by extensive land management, permanent fields with short fallow phases, ploughing, the use of animal dung as fertilizer, and grazed woodlands. The first phase, comprising the Old and Middle Neolithic, is characterized by hoe-farming only on very fertile soils and a very restricted set of crops. For the second phase, comprising the Young, Late and Final Neolithic, a slash-and-burn-like agricultural system is most probable. During the Late and Final Neolithic, this cultivation system with fire use and shifting fields was gradually practised on permanent fields and was modified, leading finally to the "Extensive ard" land use system with fertilizer and ploughing instead of burning. © 2014 Springer-Verlag Berlin Heidelberg.

Hascher M.,Landesamt fur Denkmalpflege im Regierungsprasidium Stuttgart
WasserWirtschaft | Year: 2013

The EU floods directive initiates the assessment and management of flood risk to reduce adverse consequences for cultural heritage as an explicit task. As a result more than 3 500 cultural monuments, museums, archives etc. have to be considered within the management planning process in Baden-Württemberg. The assessment of flood risk is based on the probability of floods and the vulnerability of each object. A first level assessment is processed with a geographical information system. Municipalities as well as responsible authorities check the first level assessment. To support the activities of concerned stakeholders' information about diverse aspects of preparedness and recovery is provided. Usually stakeholders set up object-specific emergency response plans. These plans have to be coordinated with response planning on local level and vice versa.

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