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The mountainous region of northwest Greece has often been cited as a possible area for the existence of temperate tree taxa during the last glacial. This series of papers examines the vegetational history and sedimentary history of two small basins in the Pindus mountain range of northwest Greece. The two basins are 18 km apart but at contrasting heights of 285 and 1800 m. The present paper describes results from the lowland basin of Gramousti lake. Techniques of pollen analysis, plant macrofossil analysis, sediment chemistry, mineral magnetics and radiocarbon dating are employed to reconstruct both the vegetational and sedimentary history of the basin. The sequence extends c. 14000 BP to c. 1000 BP. Palaeobotanical studies suggest that, during the lateglacial, vegetation in this lowland region was dominated by herbaceous taxa indicative of an open environment. Of the trees, only Quercus and Pinus were present, in low numbers. The lateglacial/postglacial transition was represented by an expansion of oak woodland and a reduction in steppe vegetation. Quercus dominated woodland persisted throughout much of the postglacial and became more diverse at c. 7500 BP with the arrival and expansion of Carpinus orientalis/Ostrya carpinifolia. Anthropogenic intervention at c. 4500 BP was probably responsible for a reduction in the oak woodland and the formation of a vegetation type similar to present day which is dominated by herbaceous taxa and chew-resistant shrubs such as Quercus coccifera and Paliurus spina-christi. [ABSTRACT FROM AUTHOR]

This paper presents macrofossil data and additional pollen analyses from the Quaternary sites previously described in Oldfield (1967). Pollen evidence presented in that paper from Bidart Plage Series B (Bidartian) and Senix Series 1 (Moulignan and Senixian) is amplified and extended by more detailed and comprehensive diagrams. The additional pollen-analytical evidence from the Bidart section confirms the importance of a Castanea-dominated pollen assemblage zone within the Bidartian Interglacial. The new diagram from Senix shows that the Moulignan major biostratigraphic subdivision is likewise interglacial in character. The late-temperate and post-temperate stages of this interglacial are well represented by the Senix and Mouligna Cliff pollen sequences now published. The macrofossil evidence from Bidart Series B(Bidartian), Mouligna Cliff MC3 (Ilbarritzian) and Marbella (Marbellan) is represented on a quantitative basis using large and volumetrically equivalent samples from each level. The main additions to the flora from these macrofossil diagrams are a wide variety aquatic and semi-aquatic species including, for the Bidartian, Ludwigia palustris and for the Marbellan, Aldrovandra vesiculosa and Proserpinaca cf. palustris a North American species not previously recorded in Post-Tiglian deposits from Europe. From Bidart, there are also interesting macrofossil records of woody warm temperate taxa, for example Chamaecyparis thyoides, Cotoneaster acuticarpa and Ostrya cf. carpinifolia. The non-aquatic macroflora from Marbella is dominated by Erica species the seeds of which have been identified largely on the basis of the fine detail of their seed coats revealed by Scanning Electron Microscopy (Huckerby, Marchant and Oldfield, 1972). [ABSTRACT FROM AUTHOR]

Pollen grains are microscopic so their identification and quantification has, for decades, depended upon human observers using light microscopes: a labour-intensive approach. Modern improvements in computing and imaging hardware and software now bring automation of pollen analyses within reach. In this paper, we provide the first review in over 15 yr of progress towards automation of the part of palynology concerned with counting and classifying pollen, bringing together literature published from a wide spectrum of sources. We consider which attempts offer the most potential for an automated palynology system for universal application across all fields of research concerned with pollen classification and counting. We discuss what is required to make the datasets of these automated systems as acceptable as those produced by human palynologists, and present suggestions for how automation will generate novel approaches to counting and classifying pollen that have hitherto been unthinkable. [ABSTRACT FROM AUTHOR]

Few studies have examined patterns of pollen deposition or the relationship between vegetation and pollen assemblages at the small scale. This paper examines the representation of both individual taxa and whole plant communities in modern pollen spectra. Micro-scale variations in modern pollen deposition were studied in three alpine plant communities on Storbreen glacier foreland, southern Norway; a pioneer community; a Salix-shrub community; and an ericaceous heath community. The relationships between vegetation and modern pollen deposition and the variability of these relationships at the local scale were investigated within 16 × 1 m²-quadrats. The data were classified using two-way indicator-species analysis (TWINSPAN) and ordinated using detrended-correspondence analysis (DCA). In addition, the pollen and vegetation data were ordinated simultaneously, using canonical correspondence analysis (CCA). The effect of removing arboreal pollen from the pollen sum was examined. The three plant communities were distinguished successfully by multivariate statistical techniques, using both pollen data and vegetation data. However, within the communities there was high variability in pollen deposition, which was most pronounced in the Salix-shrub community. The abundance of individual taxa in the vegetation was compared with their representation in the pollen spectra. The strongest relationships were shown by Salix, Ericales, Empetrum and Lycopodium. Certain taxa showed consistent, reproducible patterns of behaviour. These patterns provided valuable evidence for separating contrasting plant communities. Comparison of modern pollen-vegetation relationships of this kind with pollen data from Holocene and Pleistocene sites is important to improve the reconstruction of past plant communities. [ABSTRACT FROM AUTHOR]

This paper describes palaeoecological studies at Abernethy Forest by means of pollen and macrofossil analysis and radiocarbon dating. It also illustrates the value of stratigraphic macrofossil analysis in conjunction with pollen analysis in increasing the range and detail of palaeoecological reconstructions of past vegetation and environment. A new, large diameter core from Abernethy Forest was radiocarbon dated, and the presence of Late Devensian sediments was confirmed. Clear vegetational changes were recorded. A pioneer grass-sedge vegetation colonized the bare moraine. It developed into a shrub tundra, dominated by Empetrum and Betula nana as a result of the climatic warming during Allerød time. The Younger Dryas climatic deterioration led to the formation of species-rich open vegetation, in which Artemisia was very abundant. At the opening of the Flandrian, at about 9700 B.P., Juniperus and. Betula nana scrub developed, which was later colonized by tree Betula and then Corylus. From about 7225 B.P. Pinus dominated the forest. Throughout, the specific determinations and local derivation of macrofossils enhanced the reconstruction of the upland vegetation. In addition, macrofossils provided the majority of the evidence for the progression of the hydrosere through lake to bog communities. The complementary nature of pollen and macrofossil analyses from the same core is emphasized by a direct comparison of seed and pollen influxes. [ABSTRACT FROM AUTHOR]