Organic Matter Utilization and Destruction in Water Bodies at Different Trophic Level

It has been established that phytoplankton actively takes up low-molecular organic compounds, while high-molecular organic matter is utilized mainly by bacterioplankton. It has been found that algae utilize high-molecular compounds only in the presence of bacteria, because the latter take up final products of hydrolysis rather than release lytic enzymes into the environment.     

Studying seasonal dynamics of surface water pollution in Lower Volga Basin

The results of environmental monitoring of surface-water quality in the Lower Volga Basin are given. The results of regular observations are differentiated. Water pollution is assessed based on the criterion of seasonal occurrence of chemicals in water at gage sections classified by zonal principle. An integrated estimate demonstrates considerable variations within a year and an increase in the normal annual concentrations of some pollutants of both natural and anthropogenic origin.     

Suppression of Alga Blooming by Zooplankton Filter Feeders in Small Water Bodies

The study is focused on the ability of filterers–phytophages Daphnia longispina O.F. Mueller to suppress blooming in shallow-water bodies in Moscow oblast. The effect of phytoplankton development on the composition of daphnia populations is studied. With the predominance of small-cell (<40 μm in length) green, yellow-green, and euglena algae in the phytoplankton and, accordingly, in the nutrient budget of daphnia, the biomass of D. longispina (12 mg/L) is 1.5–6.0 times greater than that in the water bodies where the phytoplankton shows the predominance of Aphanizomenon flexuosum Komárek et Ková?ik (filamentous cyanobacteria) and Volvox polychlamys Korshikov (cenobial green algae). The mean fertility of the reproducing organisms of D. longispina (the number of eggs per female reached 11) was also higher in the former case.     

Suppression of Phytoplankton Blooming in Water Bodies with the Use of Filtering Zooplankton in Flow-Through Ecosystems

Water Resources - The study has been focused on the population composition dynamics and trophic relationships of Simocephalus vetulus (O.F. Müller, 1776) in the absence of the food stress of...