The priority programme ''Changes of the Geo-Biosphere'' aimed to reconstruct the environmental history of central Europe with emphasis on the time interval from 9000 to 5500 cal BP (time-slice II), coinciding with the Holocene climatic optimum. During this period, the onset of human activities such as settlement, agriculture and animal husbandry caused environmental changes. Studies of different landscape units in Germany were carried out to identify these anthropogenically induced changes and to distinguish them from natural effects on the environmental system. The investigated archives included laminated lake sediments, fluvial sediments, colluvia and soils, speleothems, peat and coastal sediments. The different archives were examined using refined research methods including a variety of sedimentary and geochemical analyses, together with pollen analysis and dating methods for the establishment of a reliable chronology. The results of the various research groups are summarised and critically discussed. Based on these results, the climatic optimum can be subdivided into three periods: (1) the Early Atlantic from 9000 to 7500 cal BP with negligible human impact and stable environmental conditions; (2) the Late Atlantic during Early and Middle Neolithic from 7500 to 6300 cal BP with pollen evidence for vegetation changes but only negligible changes detectable in other proxy records; and (3) the Late Atlantic during the Younger Neolithic (Jungneolithikum), after 6300 cal BP, with human impact observed in many archives and proxy records especially in the pollen record but also in lacustrine and fluvial sediments. During the whole climatic optimum natural causes, such as minor shifts of temperature, did not induce substantial environmental changes, though some changes, such as temporary droughts, may have facilitated and amplified the observed human impact. r

Abstract:The Rhine river system can look back on a long history of human impact. Whereas significant anthropogenic changes to the river channel started only 200 years ago, the impacts of land use have been felt for more than 7500 years. Here, we review results from several case studies and show how land-use change and climate impacts have transformed the fluvial system. We focus on changes in sediment delivery pathways and slope-channel coupling, and show that these vary in time and depend on the magnitude of a rainfall event. These changes must be accounted for when trying to use sediments as archives of land-use change and climatic impacts on fluvial systems. For example, human impact is recorded in slope deposits only as long as rainfall intensity and runoff generation do not exceed the threshold for gullying. Similarly, climatic impacts are only recorded in alluvium when both the landscape is rendered sensitive by human activities (e.g. deforestation) and rainfall thresholds for gullying are exceeded.

No abstract

No abstract

No abstract

No abstract

No abstract

Abstract. The current state of research about ancient settlements within the Nile Delta allows the hypothesizing of fluvial connections to ancient settlements all over the Nile Delta. Previous studies suggest a larger Nile branch close to Kom el-Gir, an ancient settlement hill in the northwestern Nile Delta. To contribute new knowledge to this little-known site and prove this hypothesis, this study aims at using small-scale paleogeographic investigations to reconstruct an ancient channel system in the surroundings of Kom el-Gir. The study pursues the following: (1) the identification of sedimentary environments via stratigraphic and portable X-ray fluorescence (pXRF) analyses of the sediments, (2) the detection of fluvial elements via electrical resistivity tomography (ERT), and (3) the synthesis of all results to provide a comprehensive reconstruction of a former fluvial network in the surroundings of Kom el-Gir. Therefore, auger core drillings, pXRF analyses, and ERT were conducted to examine the sediments within the study area. Based on the evaluation of the results, the study presents clear evidence of a former channel system in the surroundings of Kom el-Gir. Thereby, it is the combination of both methods, 1-D corings and 2-D ERT profiles, that derives a more detailed illustration of previous environmental conditions which other studies can adopt. Especially within the Nile Delta which comprises a large number of smaller and larger ancient settlement hills, this study's approach can contribute to paleogeographic investigations to improve the general understanding of the former fluvial landscape.