STUDIES OF MACROZOOBENTHOS IN THE UPPER OB RIVER CATCHMENT

Abstract

The paper presents a review of studies of macroinvertebrates dwelling in waterbodies and watercourses of the Upper Ob catchment (southern part of West Siberia). Major periods of zoobenthos studies were distinguished depending on the scope and goals of the activities performed. Studies have focused on determining the taxonomic diversity, quantitative indicators and conditions for the formation of benthic communities influenced by natural and anthropogenic factors. Studies of the Upper Ob zoobenthos fall in four periods: before 1925, 1925–1977, 1977–1995, and since 1995 onwards. In the first period, the research was mainly of a reconnaissance nature, aiming to identify the species composition of aquatic ecosystem inhabitants. The second period differed from the previous one in having well-organized scientific expeditions. During that period, general information on the hydrology and biology of key river catchments and lakes of the Upper Ob was gathered, and an in-depth study of the ecology, biomass and seasonal dynamics of benthic invertebrates began. The third period was marked by the construction of hydraulic engineering facilities, wherefore research mostly concentrated on studying benthic invertebrates’ response to changes in their habitat. In the ongoing (fourth) period, studies of large waterbodies in the Upper Ob catchment continue, the amount and spectrum of research has broadened, with studies of local benthic communities moving to the foreground. Much attention is given to the state of the environment as indicated by characteristics of benthic invertebrates. Because of the large size of the Upper Ob catchment and inaccessibility of some sites, the level of hydrobiological research is highly variable across the catchment.