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Etude palynologique sur sept excavations de la compagnie des eaux dans le suffolk. Presentation de la stratigraphie, interpretation des dates et place du «Norwick Crag» dans les series

Summary The East Anglian Pleistocene succession records eight temperate stages with forest and also interstadials with forest in two of the intervening cold stages. The forest histories of these temperate stages and interstadials are described. The records through the Pleistocene of the tree genera involved are considered. The forest assemblages in each of four substages of the temperate stages (pre-temperate, early-temperate, late-temperate, post-temperate) are compared. The development of heath in the temperate stages is also examined. Floristic and phytogeographic changes indicated by the palaeobotanical evidence give information on Tertiary-relic genera and on extinctions, and have a bearing on the problem of the history of cold stage refugia. The success or failure of particular genera in response to the stress of climatic change is discussed. Finally, comparisons are made with Pleistocene forest history in north-west Europe.

SUMMARY The relation between pollen deposition and phytosociology of 11 plant communities on the island of Ceann Ear, Monach Isles, has been studied. The relation of the phytosociology (frequency, Domin rating) of each community to the pollen analysis of a sample within it is described and the recognition of each community by its pollen spectrum is discussed. The representation of each pollen taxon in the pollen analyses in relation to the flora is tabulated, resulting in a classification of types of representation, from widespread to local to absent. The minimum percentage of pollen of off-island taxa is low (16%), over half being longdistance transport of Betula and Pinus. The frequency of off-island pollen is considered in relation to the frequency of community and out-community pollen, and various features of a plant community are suggested as possible factors in determining the relationship: height of vegetation, exposure, rate of local pollen deposition and the nature of the material trapping pollen. The significance of the results for the interpretation of fossil pollen spectra with high non-tree pollen frequencies (cold stages, post-Mesolithic clearances) is considered in relation to the reflection of a mosaic of plant communities and of regional plant communities in the pollen rain, to long-distance pollen transport and to grazing.

SUMMARY A pollen diagram from the pre-Pleistocene marine sediments near Orford, Suffolk, shows the presence of a forest flora, mainly coniferous, with a number of exotic genera of Eastern Asian/North American affinity, including Sequoia-type, Sciadopitys and Taxodium-type. It is suggested that this pollen assemblage may be Brunssumian (Lower Pliocene) in age.

SUMMARY A pollen diagram from freshwater sediments resting on glacio-fluvial outwash at Trysull, Staffordshire, England shows a sequence relating to the development of temperate stage forest. Correlation with a nearby Hoxnian site at Nechells, Birmingham is suggested.

SUMMARY The history of the application of palaeobotany to the development of Pleistocene stratigraphy in Britain is reviewed. Problems arising in the interpretation of pollen assemblages are discussed from palaeobotanical and stratigraphical points of view. Problems of correlation and nomenclature are also discussed.

SUMMARY The zonation of pollen diagrams in relation to the necessity for correct biostratigraphical subdivision is discussed, and a process of correlation of pollen diagrams to a chronostratigraphical framework is outlined.

summary The stratigraphy of the Pleistocene deposits in the area of Chelford is described. The palaeobotany of a layer of organic mud within the Middle Sands of the Pleistocene sequence is described, and it is shown that the organic mud was deposited during a cool period in which a Betula-Pinus-Picea forest was the local dominant vegetation. The climatic indications given by the flora and vegetation are discussed. The organic mud is tentatively correlated with an interstadial period early in the Last Glaciation; the implications of this correlation are briefly mentioned.