Abstract
The Ilek River, one of the most polluted water bodies in the Ural–Caspian Basin, is subject to considerable anthropogenic pressure. This impact is primarily caused by the inflow of heavy metals (Cr, Pb, Fe, Mn), boron, petroleum hydrocarbons, and organic pollutants, including surfactants, COD, and BOD₅. The aim of this study was to conduct a comprehensive bioindication-based assessment of organic pollution in the river channel. To achieve this, we applied the saprobity index of macrophyte communities in combination with instrumental analysis of the water’s physicochemical parameters. The study further examined the remediation potential of six macrophyte species (Ceratophyllum demersum, Lemna minor, Eichhornia crassipes, Pistia stratiotes, Typha latifolia, and Phragmites australis) for removing priority pollutants. This analysis was supported by a systematic review of scientific publications indexed in Scopus between 2018 and 2025.