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Different tree species influence litter decomposition directly through species-specific litter traits, and indirectly through distinct modifications of the local decomposition environment. Whether these indirect effects on decomposition are influenced by tree species diversity is presently not clear., We addressed this question by studying the decomposition of two common substrates, cellulose paper and wood sticks, in a total of 209 forest stands of varying tree species diversity across six major forest types at the scale of Europe., Tree species richness showed a weak but positive correlation with the decomposition of cellulose but not with that of wood. Surprisingly, macroclimate had only a minor effect on cellulose decomposition and no effect on wood decomposition despite the wide range in climatic conditions among sites from Mediterranean to boreal forests. Instead, forest canopy density and stand-specific litter traits affected the decomposition of both substrates, with a particularly clear negative effect of the proportion of evergreen tree litter., Our study suggests that species richness and composition of tree canopies modify decomposition indirectly through changes in microenvironmental conditions. These canopy-induced differences in the local decomposition environment control decomposition to a greater extent than continental-scale differences in macroclimatic conditions. [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]

The paper presents a brief and personal history of the main developments in British vascular plant taxonomy and distribution studies in a European setting since the Second World War. It assesses the importance of the 'European view', and considers recent and current work under two main heads: the factual information itself, and the presentation of the facts, especially in the form of dot distribution maps. [ABSTRACT FROM AUTHOR]