(View exact match)pollen diagramSYNONYMS OR RELATED TERMS: pollen spectrum
DEFINITION: A diagram produced after the analysis of the pollen from a column of peat or other soil. Pollen diagrams consist of a number of graphs, showing the fluctuations of different pollen types through a sediment or soil. The vertical axis of the diagram represents depth through the deposit and is therefore roughly related to time, as the deeper layers are the oldest. Each small graph represents the changing frequency of one pollen type, either as a percentage (proportional pollen counting) or as an absolute frequency (absolute pollen counting). It is often possible to split the diagram up into a number of pollen zones, each dominated by high frequencies of a particular pollen type or types.
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DEFINITION: A site in Suffolk, England, where John Frere discovered Stone Age implements (hand axes) among some fossilized bones of extinct animals in 1797. At that time, it was believed that the Earth had been created in 4004 BC. In reporting his findings, Frere suggested that the remains came from a time considerably earlier than that. His report was politely received, but it wasn't until 1956 that it was demonstrated that the lake clays had a distinctive Hoxnian pollen diagram and the Acheulian hand axes were associated with this.LehringenCATEGORY: site
DEFINITION: A Middle Palaeolithic site near Bremen in north Germany (Lower Saxony), where organic muds revealed a pollen diagram of the last Interglacial. In these muds, a yew wood spear broken into several pieces was found. It passed between the ribs of the skeleton of an Elephant of Elephas antiquus type. The tip was finely shaved to a point and fire-hardened; the spear was evidently used for thrusting.pollen analysisSYNONYMS OR RELATED TERMS: palynology
DEFINITION: The study of pollen grains in soil samples from an archaeological site which provides information on ancient human use of plants and plant resources. This technique, which is used in establishing relative chronologies as well as in environmental archaeology, was developed primarily as a technique for the relative dating of natural horizons. Pollen grains are produced in vast quantities by all plants, especially the wind-pollinated tree species. The outer skin (exine) of these grains is remarkably resistant to decay, and on wet ground or on a buried surface, it will be preserved, locked in the humus content. The pollen grains of trees, shrubs, grasses, and flowers are preserved in either anaerobic conditions or in acid soils. Samples can be taken from the deposits by means of a core or from individual layers at frequent intervals in a section face on an archaeological site. The pollen is extracted and then concentrated and stained and examined under a microscope. Pollen grains are identifiable by their shape, and the percentages of the different species present in each sample are recorded on a pollen diagram. A comparison of the pollen diagrams for different levels within a deposit allows the identification of changes in the percentages of species and thus changes in the environment. As a dating technique, pollen has been used to identify different zones of arboreal vegetation which often correspond to climatic changes. The technique is invaluable for disclosing the environment of early man's sites and can even, over and series of samples, reveal man's influence on his environment by, for example, forest clearance. The sediments most frequently investigated are peat and lake deposits, but the more acid soils, such as podsols, are also analyzed. Radiocarbon dates may be taken at intervals in the sequence, and it is possible to reconstruct the history of vegetation in the area around the site where the samples were taken. Palynology plays an important role in the investigation of ancient climates, particularly through studies of deposits formed during glacial and interglacial stages of the Pleistocene epoch.pollen zoneCATEGORY: technique
DEFINITION: A division that can be drawn across a pollen diagram on the basis of fluctuations in pollen types. Each pollen zone is dominated by high frequencies of a particular pollen type or types. In recent years, many palynologists have abandoned general zonation schemes and instead have divided their pollen diagrams into 'pollen assemblage zones' (p.a.z.). These are based simply on the pollen fluctuations seen in each particular diagram and can therefore take account of local variation in the history of vegetation.