Аннотация
The study of zoobenthos was conducted in July 2021 on small and medium-sized rivers of the Upper Volga from the village. Selizharovo to the Ivankovo reservoir in areas poorly affected by economic activity. The task was to study the features of river biocenoses in landscapes of different types. The western part of the territory under consideration is elevated (Valdai upland), the eastern part is low–lying (Upper Volga lowland); watercourses in these areas differ in flow velocity and type of bottom sediments. These two factors lead to differences in the composition of bottom biocenoses: in upland rivers, the number of species of mayflies, brooks, and spring wort is significantly higher than in watercourses of low-lying territories. There is a connection in the series: landscape – hydrological characteristics of rivers – bottom biocenoses. Water quality indicators – the Woodiwiss and BMWP indices indicate the uncontamination of watercourses. At the same time, the indicators themselves naturally change under the influence of landscape (and hydrological) parameters. Therefore, when conducting a biological indication of the Upper Volga watercourses, it is recommended to take into account the landscape features of the formation of bottom biocenoses.