The Różany Strumień catchment located in the north of Poznań is an example of a small anthropogenically-induced catchment. The main aim of this study is to analyse the variability of selected physical and chemical properties of surface waters in the catchment area in the years 1988-2012. It was found that surface waters in the catchment can be classified as hard and very hard, with slightly basic pH. The deterioration of Różany Strumień water quality concerns chemical oxygen demand, conductivity, chlorides, sodium, ammonia nitrogen and nitrite nitrogen concentrations. The authors of the study have noticed a decrease in the amount of phosphates and sulphates in the water. As observed, the hydrogeochemical type of water changed from calcium-hydrogen carbonate-sulphate into calcium-sodium-hydrogen carbonate-sulphate-chloride. Changes in water chemistry are probably a result of anthropogenic impacts, and they can be associated with the transformation of land use in the catchment area, i.e. the ongoing urbanization of the area.
At present, concentrations of pharmaceuticals in surface and ground waters are low; however, even low concentrations of certain substances may prove very harmful. One of such pharmaceutical drugs is diclofenac, a popular non-steroidal anti-inflammatory drug (NSAID). For this reason, it is important to determine its mobility in groundwater and to estimate parameters of migration. Authors conducted column tests for two porous media: an artificial one, consisting of glass granules, and a natural one, i.e., sandur sand obtained from a site north of the city of Poznań (Poland). During the test, impulse breakthrough curves of chloride ions and diclofenac were recorded. The results were used to identify a specific sorption model and to determine values of migration parameters. Solutions of the inverse problem using optimisation methods and of equations of mathematical migration models were carried out in a MATLAB environment. Based on test results, the mobility of diclofenac is shown to be very high and comparable to that of chloride ions. The tests also revealed a slight and irreversible sorption of diclofenac on grains of both porous media.