Water pollution hotspots and the role of riparian vegetation in industrial area

With the ongoing expansion of urban areas globally, industrial zones are increasingly integrated into city landscapes. These zones, characterised by a high density of industrial facilities from diverse sectors, can pose significant threats to the natural environment, particularly to aquatic ecosystems. This study aims to assess the influence of an urban area containing a designated industrial zone on spatio-temporal variations in river water chemistry and to identify critical zones of water quality degradation. The research was conducted on the Drwinka River, located in Niepołomice, southern Poland. Findings revealed abrupt shifts in water chemistry along the river, primarily driven by point-source wastewater discharges. Industrial activity led to a marked increase in water salinity, largely due to elevated concentrations of sodium chloride (NaCl). Additionally, wastewater introduced organic and inorganic forms of nitrogen, phosphorus, and carbon into the river, though the negative effects of these pollutants diminished downstream. This attenuation was attributed to the buffering capacity of riparian vegetation, particularly aquatic plants (hydrophytes). Seasonal changes in catchment biological activity also had a significant impact on the concentrations of biogenic elements in the river water. Overall, the study underscores the importance of riparian zones in mitigating pollution and highlights the need for careful monitoring and management of industrial discharges within urbanised catchments.