. This paper critically appraises the evidence for a succession of ice‐dammed lakes in the central Strait of Magellan (c. 53°S) c. 17 000–12 250 cal. yr BP. The topographic configuration of islands and channels in the southern Strait of Magellan means that the presence of lakes provides compelling constraints on the position of former ice margins. Lake shorelines and glacio‐lacustrine sediments have been dated by their association with a key tephra layer from Volcan Reclús (c. 15 510–14 350 cal. years bp) and by 14C‐dated peats. The timing of glacial lake formation and associated glacier readvances is at odds with the rapid and widespread glacier retreat of the Patagonian ice fields further north after c. 17 000 cal. yr bp, suggesting rather that the lakes were coeval with the Antarctic Cold Reversal and persisted to the Late‐glacial/Holocene transition. This apparent asymmetrical latitudinal response in glacier behaviour may reflect overlapping spheres of northern hemisphere and Antarctic climatic influence in the Magellan region.

This series of papers addresses the principal natural and anthropogenic environmental changes that have transformed a typical lowland Scottish landscape during the Holocene. Sediment- and pollen- stratigraphic techniques, together with radiocarbon dating, are applied in this paper to the stratigraphy of a raised bog at Burnfoothill Moss, eastern Dumfriesshire, to deduce changes in groundwater levels within the bog, and by inference, changes in effective precipitation. The basin, initially a shallow pond, was rapidly colonized by fen peat at 9600 BP, possibly during a phase of drier climate, which ended at c. 8700 BP. Short-lived fluctuations in bog-surface wetness are identified before a major change to a wetter bog surface at around 7700 cal. BP, representing the transformation from fen peat to raised moss. Anthropogenic interference with surrounding woodland is believed to have destabilized the water balance within the peat. Drier bog-surface conditions occur at c. 6700 cal. BP, and a shift to a wetter climate at around 5250 cal. BP, but a perhaps more substantial wet shift is recorded at c. 4000 cal. BP. At c. 1900 cal. BP a dry climate shift is recognized, ending at c. 1200 cal. BP. Slightly prior to the 'Little Ice Age', represented by a very wet phase before c. 400 cal. BP, is a dry period between c. 600 and 400 cal. BP.

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This contribution describes the geomorphic, stratigraphic, palaeoclimatic, palaeoecological and 14C dating evidence for the timing within the present interglacial of blanket peat initiation and extension (‘spread’) from five localities throughout the upland and northern regions of Scotland. The results suggest that blanket peat was common or abundant over much of the highland landscape within a few thousand years of the beginning of the Holocene period. Blanket peat developed either as an inevitable but rapid end-stage to soil development in this generally cold and wet climate or was promoted by climatic change. There is no evidence from this data-set that blanket peat developed as a result of anthropogenic activities. It is suggested, indeed, that farming communities successfully resisted the natural spread of peat across their fields

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This paper examines the importance of palynological site selection criteria, speci cally basin size, for the detection of vegetation mosaics and small-or local-scale human activity within a spatially diverse, mosaic landscape. Using a site selection strategy which recognizes landscape patchiness, pollen analyses from three small peat basins (10-56 m diameter) in an open, exposed upland valley (.250 m OD) provide records which are sensitive to local vegetation mosaics and small-scale, localized agriculture. The results indicate c. 4000 14 C years (4400 cal. years) of land use, with spatial and temporal variations in the valley. Contrasts between the sequences suggest that local pollen production remains an important component of the pollen rain deposited in small peat basins, even in open environments; this is especially true of palynological 'agricultural indicators'. By comparison, sites with regional pollen source areas underestimate the spatial diversity of the upland landscape, and are insensitive to small-scale human activity in an environment where the fragmentary distribution of soils suitable for agriculture favoured a small-scale, dispersed pattern of farming. It is therefore essential to match the spatial resolution of pollen records with the grain size or scale of variations in the environment under investigation in order to sense the scale of mosaics in vegetation and agriculture within patchy landscapes.

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