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Historical aerial images represent a source of information of great value for glacier monitoring, as they cover the area of interest at a well-defined epoch and allow for visual interpretation and metric analysis. Typically, the aerial images are used to produce orthophotos and manually digitize the perimeters of the glaciers for analysis of the surface extent of the glaciers, while the extraction of height information is more challenging due to data quality and characteristics. This article discusses the potential of historical aerial images for glacier modelling. More specifically, it analyses the impact of their coverage, radiometric- and geometric accuracy, state of preservation and completeness on the photogrammetric workflow. The data set used consists of scans of 300 (analog) aerial images acquired between August and October 1954 by the U.S. Air Force with a Fairchild KF7660 camera over the entire Province of Trento. For the modelling of the glaciers, different techniques such as manual stereoscopic measurement and dense image matching were tested on sample glaciers and the results were analysed in detail. Due to local radiometric saturation in a large part of the glacial surfaces and other disturbances affecting the historical images (e.g. scratches, scanning errors, dark shadows), dense image matching did not produce any valuable results, and stereo plotting could be used only on images (or image parts) with acceptable quality. The derived Digital Terrain Models (DTMs) were compared with a reference DTM obtained with dense image matching from digital aerial images acquired in September 2015 with an UltraCam Eagle sensor, and, for some glaciers, to a DTM obtained with dense image matching from scanned aerial images acquired in September 1983 with a RC30 analog camera. The differences between 1954 and 2015 DTMs showed values up to 70–80 m in height and a behaviour that is confirmed by the models employed by the glaciology experts in Trento.

Anthropogenic soils are formed by human activities. The contents of potentially risk elements are one of the most important criteria of the exploitability of such soils for the agricultural production. The aim of this paper is to assess the contents of the selected potentially risk elements in 16 areas of the Sokolov region, including 5 reclaimed areas and 11 natural soils. 116 sampling locations were analysed in total. Another aim is to analyse the relationships between the elements, using multivariate statistical methods. The contents of the risk elements studied were in most cases under the limit values. In some cases, as with Pb, they were very low compared to the limit values. In the principal component analysis, four components explaining 74% of total variability were selected. The first component (30.2% of variability) showed strong correlations with Mn, V, Ni, and Cu contents. The second component (15.8% of variability) correlated with As and Be. The third component (14.3%) correlated with Pb and Cd. The fourth component (13.7%) correlated with Zn and Cr. The mean scores of each area were projected into the component plots, which enables the assessment of the relative importance of each group of elements in each particular area. The reclaimed and the natural soils are clearly distinguished. It can be concluded that the contents of the risk elements studied do not currently present any important problem in the reclaimed areas. Nevertheless, the situation should be further monitored.