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About 750 examples of patterned ground forms at 25 sites in the High Sudetes mountains (Czech Republic) were classified using morphometric characteristics and environmental parameters. Simple parameters such as length, width and height of patterned ground were measured in the field, with additional variables of elevation, intensity of deflation and regolith grain size. The surface morphometry of patterned ground, comprising relict sorted polygons and sorted nets and active earth hummocks, was strongly influenced by site characteristics. Sorted net dimensions were affected by the intensity of deflation, which determined the micro‐relief (positive correlation), and regolith coarseness, which negatively impacted the diameter of landforms. For sorted polygons, opposite relations concerning diameter and regolith coarseness were observed. The use of both morphometric and environmental variables within canonical linear discriminant analysis was successful in classifying almost 95 per cent of landforms. The advantage of combining the two types of predictors was demonstrated by the presence of both earth hummocks and sorted polygons at wind‐swept sites, but with significantly different morphometric and regolith requirements. Copyright © 2009 John Wiley & Sons, Ltd.

The Hercynian mountain ranges were islands of mountain glaciation and alpine tundra in a Central European ice‐free corridor during the Late Pleistocene. Today they are notable areas of glacial landforms, alpine‐forest free areas, peatlands and woodlands. However, our knowledge of the Lateglacial and early Holocene environmental changes in this region is limited. We present a new multi‐proxy reconstruction of a mid‐altitude environment in the Bohemian Forest spanning this period. A core (5.2 m length) in the Černé Lake cirque (1028 m a.s.l.) was subjected to lithological, geochemical, pollen and macrofossil analysis supplemented by two optically stimulated luminescence (OSL) and 10 AMS radiocarbon dates. We determined the impact of regional and supraregional climate changes on the environment. The two most significant changes in sedimentation during the Lateglacial (17.6 and 15.8–15.5 cal. ka BP) were synchronous with regional glacial chronostratigraphy. Unlike Central European mountain ranges, in the Bohemian Forest the Younger Dryas was not coincident with glacier re‐advance, but was a dry, cold episode with low lake levels, which prevailed until the early Preboreal. Plant macrofossils indicate local establishment of Betula nana and Betula pendula/pubescens at 15.4–13.4 cal. ka BP. Comparison with Holocene records from Central Europe shows a similar immigration history of vegetation at mid and higher altitudes. The tree line exceeded an altitude of ~1000 m a.s.l. around 10.5 cal. ka BP and coincided with rapid geochemical changes in the sediment. The 8.2 ka BP event did not have any response in the sedimentary record, but corresponded to stabilization of the Picea abies population and expansion of Fagus. Fagus colonized the Bohemian Forest earlier than other Hercynian mid‐mountains, but never predominated in the composition of the forest at higher elevations. Abies alba was the last tree species that immigrated to the study area.

Sorted circles and polygons are widespread features of periglacial landscapes, but the controls on their development remain poorly understood, impeding their use as palaeoenvironmental indicators. We investigate the relationship of sorted circles and polygons to altitude in the northern Billefjorden area, central Svalbard. The patterns occur in two distinct elevation zones, below 200–250 m asl and above 600 m asl. The higher‐elevated patterns have smaller diameters and shallower sorting depths due to a thinner active layer at higher elevations, suggesting that sorted patterns can indicate climate conditions and ground thermal state when the patterns initiated. Geology is believed to be of less importance for pattern morphology in the study area, causing only its fine‐scale variations. The pattern diameter‐to‐sorting depth ratios have a median value of 3.57, consistent with previous studies and theoretical models of patterned‐ground formation involving circulation mechanisms. Large‐scale sorted patterns may develop over centennial timescales in this high‐Arctic environment. They are probably not in equilibrium with present‐day climate conditions and have probably formed throughout the Holocene. Copyright © 2017 John Wiley & Sons, Ltd.