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The study analyses a 7.5-m-thick sedimentary succession deposited in the largest sandur (the Gwda sandur, a glacial outwash plain) in NW Poland, during the late Weichselian (MIS 2). Although the study site is located in the distal zone of the sandur, its sedimentological features and palaeohydrological parameters reflect the presence of an energetic, powerful environment typical of the proximal zone. Three sedimentary units were recognized in the studied sedimentary succession: (1) lower unit — fine-grained sands with ripple cross-lamination and horizontal lamination; (2) middle unit — gravelly coarse-grained sands and sandy gravels with planar cross-stratification; and, (3) upper unit — sands and gravelly sands with trough cross-stratification. Although the age of deposition of the sandur is accepted to be convergent with that of end-moraines of the same phase, the sediments in the distal zone of the Gwda sandur correlate with an earlier glaciation phase/subphase. Our findings hint at a complex problem: large sandurs such as the Gwda sandur were probably deposited over a long time, and their successions might record the textural and structural features of the proximal subenvironment, even in their distal parts due to deglaciation-related shifting of the proximal zone of a sandur. This paper presents a new approach to analysing the depositional processes in large sandurs, shows a new light on glaciofluvial water supply dynamics of distal parts of sandurs, and may solve several fundamental problems related to the sandur deposition. [ABSTRACT FROM AUTHOR]

A diverse terrain is one of the essential natural features of a balanced landscape and the specific features of its geomorphological units (sandur, moraine) contribute to regional diversity. The present work describes research designed to verify the hypothesis that the diversity of flora in the ecotone zone of woodland in Poland relates to variability both in the terrain and in land use. By using phytoindication it was possible to assess differentiation in the surfaces under study. It was found that land use (agricultural and forest use) was responsible for the occurrence of a positive interrelationship between trophy and synanthropisation values, no matter what kind of geomorphological unit there was. On the basis of the species composition in the areas under research, within the ecotone zone of woodland, it was established that in the area within moraine which had previously been used agriculturally there was a cumulation of species due to habitat diversity in ecological niches resulting from the terrain, the amount of mineral nutrients in the soil and a large amount of, in particular, native and neutral species in the gene pool. [ABSTRACT FROM AUTHOR]