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Sphagnum is the major genus in northern peatlands that contributes to peat formation and carbon sequestration. Sphagnum growth in summer has been fairly well studied but the information about growth in autumn and winter is limited. Therefore, we studied how the growth of Sphagnum is seasonally distributed with a particular interest on possible winter growth. The linear increment and biomass production of three Sphagum species was measured in three Northern European bogs over a year. In all sites, our results indicate the highest annual linear increment in S. angustifolium (28 mm), followed by S. magellanicum (20 mm) and S. fuscum (13 mm), but the biomass production was fairly even among the species (189, 192 and 215 g m −2 , respectively). Both linear increment and biomass production depended mostly on meteorological parameters rather than ecophysiological or microsite properties. The seasonal measurements revealed a significant linear increment and biomass production during the winter that accounted for ca. 10% and ca. 5% from the annual values, respectively.Moreover, the mean daily rates of linear increment in autumn often exceeded the increment in summer. Our results thus indicate the ability for year-around growth of Sphagna if the conditions are favorable, including during boreal winter. K E Y W O R D Sbiomass production, linear increment, peat moss, peatland, seasonality

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Relative sea level (RSL) changes and the palaeogeography of a Neolithic hunter-fisher-gatherer settlement site on the former shore of the Gulf of Finland in the city centre of Tallinn were reconstructed by implementing GIS in landscape modelling based on archaeological, sedimentary and shore displacement data. AMS radiocarbon dating of mammal bones from the cultural layer suggests the existence of the hunter-fisher-gatherer settlement around 5.1–4.8 cal. ka BP on a seaward inclining sandy beach of Tallinn palaeo-bay c. 100 m from the Litorina Sea shoreline and at about 2.4 m above the coeval sea level. The shoreline passed the study site at about 5.8 cal. ka BP and retreated towards northeast with an average speed of 13 m per century, while the RSL lowered by c. 2.5 mm annually. Combining radiocarbon dates of terrestrial and marine mammal bones from the Neolithic cultural layer, a marine reservoir effect of 350 14C years for the brackish-water Baltic Sea was calculated. By using high-resolution archaeological data in combination with RSL and other geological proxies, we demonstrate new possibilities to reconstruct the palaeoenvironment of deeply buried coastal settlement sites and to predict a possible continuation of the cultural layer in heavily built-up areas.

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