The impact of multiple years of underground mining of minerals on changes in the elevation of an urban area has been evaluated using the case study of Bytom in southern Poland. Between 1883 and 2011, that city experienced changes in absolute minimum (from 250.0 to 243.0 m a.s.l.) and maximum (from 340.0 to 348.4 m a.s.l.) elevations. During that period, the difference between minimum and maximum elevations increased from 90.0 to 105.4 m. The consequence of underground mining has been the formation of extensive subsidence basins with a maximum depth of 35 m. Where the terrain became raised, its elevation rose most commonly by 1.1 m to 5.0 m, with maximum increase in elevation caused by human activity amounting to 35 m. The rate of anthropogenic subsidence in the city between 1883 and 2011 averaged 43 mm/year (5.5 m over the study period).

An assessment was carried out of the anthropogenic enrichment of the chemical composition of the bottom sediments of water bodies situated in an area with an urban and industrial character (63.7% of the total area). The endorheic catchments of the water bodies studied are lithologically uniform with sandy formations accounting for more than 90% of the surface area. On the basis of geoaccumulation index values, it was found that the bottom sediments of the water bodies studied were contaminated with the following elements: Cd, Zn, S, As, Pb, Sr, Co, Cr, Cu, Ba, Ni, V, Be, in degrees ranging from moderate to extreme, with lower contamination (or absence of contamination) with the same elements being found in the formations present in the vicinity and in the substrate of the basins of water bodies. It was found that one consequence of the fact that these water bodies are located in urban and industrial areas is that there is anthropogenic enrichment of the chemical composition of bottom sediments with certain basic components (organic matter, Mn, Ca and P compounds) and trace elements: Cd, Zn, Pb, Sb, As, Cu and Co, Br, Ni, S, Be, Cs, Sr, V, Cr, Sc, Ba, U, Ce, Eu and Th, with virtually no enrichment of sediments with the other basic and trace components analysed (La, Rb, K₂O, Nd, Sm, Na₂O, Hf, SiO₂, Zr).

Jezioro Lake is the only natural lake in southern Poland outside mountainous areas to have existed continuously since the Pleistocene. The record of environmental change in the Late Vistulian (Weichselian) and Holocene is preserved in the deposits and landforms around the lake. This paper presents the results of paleogeographical and paleoecological research that emabled us to reconstruct the history of the Jezioro Lake. At the end of the Vistulian period, the outlet of the lake was blocked by a parabolic dune moving in from the west. Limnic sedimentation was evident in the sediment core at all levels from the Holocene, with remains of Cladocera, Chironomidae larvae, and aquatic plants. The lake did not disappear at that time, although its area decreased by a factor of 12 by the end of the period. Paleobotanical research permitted the reconstruction of sequences of plant communities and changes in nutrient status and water level. An initial oligotrophic lake, as indicated by the presence of Isoëtes lacustris L., changed to a eutrophic lake, as indicated by the presence of Potamogeton natans L. and Nuphar sp., then the lake progressed to the present-day dystrophic lake that is surrounded by a swamp. The profile of organic deposits contains a record of environmental change at least since the Younger Dryas in southern Poland.

The study of bottom sediments was conducted within the basins of water bodies used for recreational purposes (e.g., bathing, fishing and diving) in the Silesian Upland and its periphery in southern Poland. Various concentrations of trace elements were found in bottom sediments, reflected by the following levels: Pb (30–3020 mg/kg), Zn (142–35,300 mg/kg), Cd (0.7–286 mg/kg), Ni (10–115 mg/kg), Cu (11–298 mg/kg), Co (3–40 mg/kg), Cr (22–203 mg/kg), As (8–178 mg/kg), Ba (263–19,300 mg/kg), Sb (0.9–52.5 mg/kg), Br (1–31 mg/kg), Sr (63–510 mg/kg) and S (0.001–4.590%). These trace elements are present in amounts that usually exceed those found in other bodies of water or are sometimes even unprecedented among bodies of water in the world (e.g., cadmium—286 mg/kg, zinc—35,300 mg/kg, lead—3020 mg/kg, arsenic—178 mg/kg). It was found that bottom sediments were contaminated to varying degrees with toxic metals, metalloids and non-metals, as evidenced by the values of geoecological indicators, i.e., the geoaccumulation index (−6.31 < I_geo < 10.90), the sediment contamination factor (0.0 ≤ $C_f^i$ < 286.0), the sediment contamination degree (4.6 < C_d < 513.1) and the ratios of the concentrations found to the regional geochemical background (0.5 < I_RE < 196.9). It was concluded that the presence of toxic elements (e.g., lead, zinc, cadmium, chromium, strontium and arsenic) in bottom sediments should be taken into account when classifying water bodies as suitable for recreational use. A maximum ratio of the concentrations found to the regional geochemical background of I_RE ≤ 5.0 was proposed as the threshold for the permissibility of recreational use of water bodies. The water bodies used for recreational purposes in the Silesian Upland and its periphery do not meet the geoecological conditions for safe use in terms of recreation and leisure activities. Forms of their recreational use that directly affect the participants’ health (e.g., fishing and the consumption of fish and other aquatic organisms) should be abandoned.

A particularly large accumulation of mining subsidence basins is characteristic for the Silesian Upland in southern Poland. This region is home to one of Europe’s largest coal basins. The objective of the study was to assess the subsidence process on the land surface in an industrialized urban area, as well as their impact on changes in the water cycle. Detailed studies were conducted in an area of 51.26 km², which covers urban areas—mainly of Świętochłowice and partly Ruda Śląska and Chorzów, as well as Bytom and Zabrze. In the period 1883–1994 land surface depressions were revealed in an area of 38.8 km², which constitutes 75.7% of the study area. In total, the endorheic areas spread over 6.9 km². Changes in land reliefs have resulted in distinct water-cycle disturbances at local and regional levels. A generalised water-cycle scheme has been developed for the mining subsidence zone. The main directions of changes in water migration within the endorheic subsidence basin have been indicated, accounting for the situation before and after land subsidence. Consequently, this results in an average excess of 1.7 hm³ of water per year in the water cycle in these areas.