Abstract
We assess the quality of surface water in water bodies located in the Middle Volga region (Russian Federation). The water quality is assessed using 19 chemical compounds and cilioplankton indicators, such as the total number of species, the abundance of each species, and, based on both of them, the saprobity index and the Shannon–Weaver diversity index (H). We classify the water quality from polluted to extremely dirty by using abiotic indicators, and from conditionally clean to dirty by means of biotic indicators. Using the logistic regression method, we are able to predict the water quality (clean or dirty) in correspondence with the species diversity index (H) and to clarify how the quality of the water is related to its physicochemical properties. The seven most significant chemical predictors of both natural origin (mineralization, hydro carbonates, and chlorides) and natural-anthropogenic origin (organic substances (according to BOD5), nitrates, total petroleum hydrocarbons, iron), identified during the stepwise selection procedure, have a substantial influence on the outcome of the model. Qualitative and quantitative indicators of development of ciliates, as well as indices calculated on their basis, allow assessing with a very high level of accuracy the water quality and the condition of aquatic ecosystems in general. The Shannon index calculated for the number of ciliates can be successfully used for ranking water bodies as “clean/dirty”.
Highlights
Throughout recent decades, the system of assessment of surface water quality has undergone significant changes
Water bodies of the Middle Volga region are subjected to varying degrees of anthropogenic impact
This affects the quality of surface water, which can be rated from contaminated to extremely dirty
Summary
Throughout recent decades, the system of assessment of surface water quality has undergone significant changes. Phytoplankton, zooplankton, and zoobenthos organisms are used as the main indicator groups. Microzooplankton organisms, in particular, infusoria, as an indicator group are not taken into account at all in this system. Many researchers admit that infusoria are an important component of the plankton community in freshwater ecosystems [2,3,4,5,6,7,8,9,10,11,12]. A convenient object for characterizing the ecological condition of water bodies by synecological approaches [13,14]. The communities of ciliates that populate water bodies with various trophic levels and distinct habitats (plankton, benthos, periphyton) differ from each other. Infusoria are highly sensitive to changes in environmental conditions and react to them before other organisms.
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
