Palaeobotanical evidence for agricultural activities in the Eifel region during the Holocene: plant macro-remain and pollen analyses from sediments of three maar lakes in the Quaternary Westeifel Volcanic Field (Germany, Rheinland-Pfalz)

摘要

As a part of the ELSA-project (Eifel Laminated Sediment Archive) new pollen and plant macro-remain analyses have been carried out on a series of Holocene lacustrine sediments from three open maar lakes of the Quaternary Westeifel Volcanic Field. In combination with already existing pollen analyses, the archaeological record and written sources, the present study casts new light on settlement activities and henceforth the development of agriculture from the prehistoric to historic times in this region. While there are clues that wood pasturing was practised in the Eifel region from the Michelsberg Culture onwards (c. 4300 cal. b.c.), the Vulkaneifel is a remote area with relatively poor soils and a humid climate and was not constantly settled until the Late Neolithic/Early Bronze Age, when cereal pollen was found regularly in the deposits. Plant macro-remains (chaff), which give us direct evidence for arable agriculture in the surroundings of the maars, were also found in layers belonging to the Early Bronze Age (c. 1900 cal. b.c.). At the same time we can observe the massive spread of Fagus sylvatica (beech) in all pollen diagrams, which was most probably caused by a combination of climatic, anthropogenic and competitive factors. Later impacts of agriculture were an abundance of crop weeds and pollen in the following Middle Bronze Age. Nevertheless human impact remained discontinuous until the Urnfield Culture (1200–800 cal. b.c.). A layer of weeds dating at the end of the Urnfield Culture was found and also flax (Linum usitatissimum) cultivation first becomes apparent. However, the subsequent Iron Age and Roman Period reveal only crop weeds and cereal pollen in slightly higher concentrations, but the abundance of Poaceae pollen at this time is most probably consistent with grazing activities. There follows compelling evidence of the importance of flax cultivation and processing at the maars from the Merovingian Period (5th century a.d.) onwards. A detailed insight into the agriculture of the High Medieval comes from flash flood layers of the 14th century a.d., where remains of Secale cereale (rye) and crop weeds reflect winter-sown cultivation of rye. Cannabis sativa (hemp) was also cultivated and processed during the medieval. Finally we can trace the Prussian reforestation in the 19th century a.d., with an increase in Pinus sylvestris (pine) and Picea abies (fir), by both pollen and plant macro-remains.