Within the scope of the conducted experiment the authors analysed the efficiency of runoff reduction by the system of extensive type green roofs. The observations were based on storm events in the area of Lower Silesia at the Agro and Hydrometeorology Station Wrocław-Swojec. The authors analysed the thickness of plant substrate, and also estimated the quality of runoff waters under the conditions of periodic atmospheric deposition. Also considered were such indicators as electrolytic conductivity, N, NO₃⁻, NO₂⁻, NH₄⁺, P, PO₄³⁻. The experiment included roof substrates designed in two variants, with known hydraulic and physical properties of the soil material. The analysis was performed for models with vegetation layer based on pumice and zelolite, covered with five plant species from the sedum family. The modelling of the hydraulic properties was conducted with variably saturated medium, using the Hydrus 1D software. The performance of systems with primary layer thickness of 11 cm and 9, 8, 7, 6 and 5 cm was estimated. The designed models reduced the average peak flows to 89%, and in addition they caused a delay in the initiation of the runoff which was dependent on the intensity and distribution of rainfalls in time, and on the initial moisture of the profiles. Simulations, performed for variable substrate thickness, permit the conclusion that in the case of thin-layer profiles (5 cm), the relative retention index was decidedly lower and amounted to 35.9% for the substrate with zeolite (originally 60.6%) and 41% for the substrate with pumice (originally 65.7%). In the case of total nitrogen and phosphates, statistical analysis revealed significant differences (p < 0.05) in relation to specific concentrations in the rainwater and in the control surface. The total nitrogen in the runoff from the green roof was nearly twice as high as that in the rainwater and amounted to, on average, 8.3 mg L⁻¹.

Green architecture, including green roofs, can limit the effects of urbanization. Green roofs soften the thermal effect in urban conditions, especially considering the significant increase in the European and global population and that a significant share of the age group, mainly the elderly is exposed to diseases caused by high temperatures. We studied runoff and the quality of water from green roof systems in Lower Silesia, within the area of the Agro and Hydrometeorology Station Wrocław-Swojec, in the years 2012–2016. In the study, two systems with a vegetation layer based on light expanded clay aggregate and perlite were analyzed. The studies were based on the assessment of peak flow reduction, rainwater volume preservation and peak wave reduction. The calculated maximum retention performance indicator, relative to rainfall, for perlite surfaces was up to 65%, and in relation to the control surface up to 49%. In addition, the quality of water from runoff was estimated in the conditions of annual atmospheric deposition, taking into account such indicators as electrolytic conductivity; the content of N, NO₃, NO₂, NH₄, P, PO₄; and the content of metals, Cu, Zn, Pb and Cd. The load of total nitrogen exceeded the values of concentration in rainwater and amounted to 7.17 and 13.01 mg∙L⁻¹ for leca and perlite, respectively. In the case of the metal content, significantly higher concentrations of copper and zinc from green surfaces were observed in relation to precipitation. For surfaces with perlite, these were 320 mg∙L⁻¹ and 241 mg∙L⁻¹, respectively, with rainwater concentrations of 50 and 31 mg∙L⁻¹.

Flooding is a phenomenon that has become more frequent in recent years due to climate change. This also includes Poland, where a flood occurred in 2024 due to the inflow of the Genoese low. The main objective of the article is to comprehensively characterize this phenomenon in the Bóbr River Basin. To achieve this objective, available hourly hydro-meteorological data from stations monitored by the Polish Institute of Meteorology and Water Management were used. On this basis, the duration, magnitude, scale of the flood, and selected runoff measures were determined. Data shows that the flood was caused by rainfall, which occurred at the highest intensity between 13.09 and 15.09. The duration of the flood was 536 h, assuming warning levels as boundary points. The average duration of the flood in all stations was 125.32 h, and its average magnitude (ratio of the highest level to the alert level)—1.53. The 10-point flood scale adopted in the article indicates that the flood affected the area around Jelenia Góra the most (average 3.10 for the entire basin). In 6 out of 22 stations, the highest water flow measurements in history were recorded in 2024. The area around Jelenia Góra was selected as the region most exposed to flooding. This work can be a compendium of knowledge in the field of understanding the mechanisms related to flooding. It may be important in the context of formulating the future water policy, developing documents related to flood protection, adaptation to climate change and sustainable development goals.

The study addresses the problem of hard coal mine closures in the Wałbrzych coal mining area and its effects on the natural environment and landscape functioning. Coal mining resulted in the degradation of the natural environment and losses on fixed assets caused by the surface subsidence. The...