The growth of urban centers has been causing interference in water quality. Because of this, it is necessary to monitor the environment of water bodies, either by quality parameters or by the application of the Rapid Assessment Protocol (PAR). In this context, this study aimed to evaluate the level of disturbance and water quality of the Água Fresca Stream, a microbasin of the Cambé stream in the municipality of Londrina, in the north of Paraná, by means of a PAR and physicochemical analyses of turbidity, electrical conductivity and pH, and microbiological analyses of heterotrophic bacteria, total coliforms and Escherechia coli (E.coli). For this, five sampling points were established and water collection campaigns were carried out in two months with different rainfall rates, being March (215.1 mm) and April (83.6 mm) of 2022. From the analysis of the PAR it is concluded that the Água Fresca Stream can be considered as an impacted stretch, also observed by the values of electrical conductivity, from 161 to 173 μS/cm. The highest concentrations of total coliforms, heterotrophic bacteria and E.coli occurred in the month with the highest rainfall, reaching concentrations of 62,600, 163,900 and 3,000 CFU/100 mL, respectively, influenced by the greater surface runoff caused by rainwater.

UDK 574.587:595.371(497.6 Sarajevo)          595.371:502.17(497.6 Sarajevo) The paper is the result of a research into the composition of benthos of the hydro-system within the protected area of Vrelo Bosne (water source of River Bosna) and the wider region during 2009 - 2010 period. The aim of the paper is to establish the state of the populations of the endemic species of amphipod Niphargus illidzensis S., get an overview of the underlying ecological conditions within the habitats, conduct a morpho-metrical analysis of the specimens and designate the new habitats of this species. By analysing the basic physical/chemical and biological (phytobenthos and macrozoobenthos) parameters a high-quality level of water inside the habitats of this endemic species of amphipods was established: the water source of River Bosna (four), stream Stojčevac and the water source in the area of Blažuj. The highest number of specimen was recorded in stream Stojčevac where the longest specimen was also noted – 22 mm. The source in the area of Blažuj (potable water bottling plant Dijamant) is the new habitat for this species which was previously only noted in the area of Avala and Topčider near Belgrade. The paper presents a comprehensive overview of the ecology and the current state of this endemic species after its repeated description dating from 1974.