Along the paper the new method called Invertebrate Bankfull Assessment method (IBA method) of determination of bankfull discharge is presented. The investigation of bankfull discharge using IBA were performed within one Polish Carpathian stream in the mountain region: the Ochotnica Stream. As an index of bankfull the existence of certain species of invertebrates was used which are present and resistant to specific water discharge conditions. The borders within a cross section of the mountain stream with a gravel bed were defined where characteristic invertebrates are present which are recognized as bankfull borders. Finally three invertebrates benches (IB-ms) were recognized which are characterized by very specific invertebrate species. Bankfull discharge was calculated up to this IB-ms and corelated using Canonical Correspondence Analysis with other values of bankfull calculated for a cross section using different bankfull.

There is a cascade of hydroelectric power plants built on the Váh River. From a water-management point of view, the natural channel is used to drain extreme discharges. During most of the year, discharges are regulated by water-management structures. These discharges are not used for energy-related purposes; therefore, it is important to determine the optimal discharge that will not negatively affect the ecosystem of the stream. The minimum balance discharge (hydro-ecological discharge) was determined based on the instream flow incremental methodology (IFIM) using the riverine habi-tat simulation system (RHABSIM). Input data were obtained from direct measurements on three reference reaches in the area between the cities Piešťany and Nové Mesto nad Váhom. Hydraulic flow characteristics were derived from three measurements at different water levels. Habitat quality was represented by ichthyofauna. Data to determine the habitat suit-ability curves of fish were obtained using a diving technique to collect video footage. The modelling resulted in the quanti-fication of the effect of discharge on ichthyofauna as a bio-indicator of habitat quality, which implied the need of 20 m3∙s–1 for a minimum balance discharge in summer.

The Brzanka Mountain Range in the Ciężkowickie Foothills has a dense river network. Unfortunately the contemporary maps contain only the names of some main rivers of the Brzanka Mountain Range. Local communities use the same set of names of rivers as cartographers, while studies in the historical geography of the Brzanka Mountain Range reveal a wealth of local hydronyms that have seemingly been forgotten. The article attempts both to reconstruct a set of hydronyms of the Brzanka Mountain Range and to explain their etymology. It shows that hydronyms change over time and that studies on local hydronyms can help restore the collection of the names of rivers in the Brzanka Mountain Range and provide interesting information related to the past of this region. Moreover, they reveal contemporary unknown facts related to the natural environment and settlement processes in the Middle Ages. A visual summary of the article is a map showing the Brzanka Mountain Range with its river network and associated hydronyms.