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    • "The inferred vegetation changes fit well with changes in pollen spectra observed for the same time period in the lacustrine deposits at Woryty near Olsztyn (northeast Poland) and the Lake Gościąż (Starkel et al., 1998;Ralska-Jasiewiczowa et al., 2003). It is of note that the onset of Corylus is recorded at these two sites around 10,500 cal yr BP as in most central European pollen diagrams (Giesecke et al., 2011) whereas it appears around 9500 in the NKZ 3C profile. This disparity may be due to dating uncertainties, especially at Lake Gościąż (Kilian et al., 2002). "
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    ABSTRACT: The Ner River valley (central Poland) underwent substantial transformation during the Weichselian–Holocene transition as a result of fluvial processes and climate changes, resulting in the establishment of its present shape in the Holocene. A multiproxy study based on organic deposits from a palaeochannel fill (Lutomiersk–Koziówki) shows that after the channel was cut off during the late glacial termination, it became a shallow oxbow, fed by local springs. In the Boreal period, the oxbow lake was also fed by precipitation and became a telmatic environment overgrown by rush and swamp vegetation. Finally, it was covered by overbank deposits. The first flooding phase (9900–9600 cal. BP) was followed by the accumulation of overbank sediments (after 9500 cal. BP) and flooding increased after ca. 9300–9000 cal. BP. Pollen data provide information on the regional vegetation context for local and regional changes. In the Atlantic period, an increase in both summer and winter temperatures is inferred from the pollen data, corresponding to an expansion of thermophilous deciduous forests. While in general, flooding phases of the Early Holocene are poorly recognised in Eastern Europe, the Lutomiersk–Koziówki site may be considered as one of the reference points for this phenomenon in the region.
    Full-text · Article · Jan 2016 · Quaternary Research
    • "While the primeval mid-Holocene forests of Central Europe are regarded as largely closed (Birks, 2005; Mitchell, 2005; more open conditions have been suggested by; Vera, 2000), the forests of the early Holocene are mostly considered rather open (Firbas, 1949; Tallantire, 2002; Giesecke et al., 2011). We arrive at an overall openness of 10e40% after the full expansion of birch, pine and hazel which may either represent open forests with a dense herbal layer ('savannah') or a mosaic of open vegetation within dense forests ('forest steppe'). "
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    ABSTRACT: The warming at the Younger Dryas–Holocene transition (∼11,600 cal. BP) triggered the rearrangement of vegetation across Europe. To better understand that response, we analysed both an extended fossil pollen data set and robust present-day site parameters from NE Germany in a data model comparison approach. This approach allowed to quantify past plant abundances in sub-regional landscape patterns, as defined by soil types and relief. Betula was the first tree taxon to expand from scattered stands that already existed during the Younger Dryas. The major tree taxa Betula and Pinus fully established after 200–400 years as largely separated stands of Pinus on well drained sandy and Betula on fertile morainic soils. Corylus started to spread after 11,200 cal. BP, yet the final expansion was delayed until ∼10,800 cal. BP. Corylus established on gleyic soils, from which it largely expelled Betula. Throughout the first two millennia of the Holocene, open grasslands existed on fine grained soils, where seasonal dryness prevented the establishment of deciduous trees.
    No preview · Article · Apr 2014 · Quaternary Science Reviews
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    • "At the scale of hundreds to a thousand kilometres within individual regions, we recorded little or no directional pattern in the Alnus expansion, i.e., sites with Alnus evidence initially occurred across the whole region, and then the number of sites increased equally. We recorded this pattern in all northern regions, including the deglaciated area of Scandinavia, corroborating the descriptions of Bennett and Birks [95] for the British Isles and Giesecke et al. [18] for the Baltic area. Such a general absence of spatial coherence of the Alnus expansion within large areas seems to be very specific in comparison with the generally observed “stepping stone” character of expansions commonly recorded for other European trees [95]. "
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    ABSTRACT: Recently, new palaeoecological records supported by molecular analyses and palaeodistributional modelling have provided more comprehensive insights into plant behaviour during the last Quaternary cycle. We reviewed the migration history of species of subgenus Alnus during the last 50,000 years in Europe with a focus on (1) a general revision of Alnus history since the Last Glacial Maximum (LGM), (2) evidence of northern refugia of Alnus populations during the LGM and (3) the specific history of Alnus in particular European regions.
    Full-text · Article · Feb 2014 · PLoS ONE
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