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Eight relict rock-slope failures (RSFs) on Skiddaw Group terrain in the Lake District, northwest England, are described. Five of the failures are rockslides, one is a product of slope deformation, and two are compound features with evidence for sliding and deformation in different sectors. As none appears to have been overrun and modified by glacier ice it is concluded that they all post-date the Last Glacial Maximum (LGM; c.21±3 cal. ka BP). Slope stress readjustments resulting from glacial and deglacial influences are considered to have weakened the slopes, and application of the term paraglacial is appropriate. Permafrost aggradation and degradation, seismic activity and fluvial erosion are among processes that may have contributed to failure at certain sites. The failures are significant as potential debris sources during future ice advances, contributing to valley widening and cirque enlargement and, possibly, for acting as sites of cirque initiation. Previously, Skiddaw Group rocks have been regarded as homogeneous and of limited resistance to the weathering and erosion associated with Quaternary glacial, periglacial and fluvial processes. These characteristics and processes have been used to explain the steep smooth slopes and rounded hills that dominate Skiddaw Group terrain. Rock-slope failure has also helped shape this terrain and should be incorporated in future interpretations of landscape development. [ABSTRACT FROM AUTHOR]

Mountain landscapes show rapid evolution, especially at high altitudes, in response to current climate changes. In addition, the greater number of routes and trails made available and the increase in tourism have caused some impacts on mountain areas. Gradual soil erosion has been observed along some hiking trails, with the latter tending to deepen, and with stronger erosion where the trail cuts the slope. Where trails cross forested areas, trees can suffer root damage from foot trampling as roots become exposed. A dendrogeomorphological study was conducted on trees along two hiking trails in upper Valtellina (Italian Alps). On the first trail, in Valle dei Forni, European larches and stone pines, mostly with exposed roots, were sampled. A mean erosion rate of 2.7 mm/a, related to deepening of the footpath, was obtained, and various degrees of root growth disturbance along the trail were observed. In particular, the growth of many sampled roots shows an increase in ring width corresponding with the moment when root exposure occurred, followed, after 3-5 years, by rapid growth suppression. The exposure of many roots has taken place since the 1980s. No significant variations in stem growth were observed, even when there were exposed and damaged roots. Along the second trail, in Valle Alpisella, exposed roots of mountain pines were analysed. A mean erosion rate of 3.2-3.7 mm/a, related to the escarpments bordering the footpath, was obtained, while no significant changes were detected in root growth. [ABSTRACT FROM AUTHOR]