Ostroumov S. A., Walz N., Rusche R. Effect of a cationic amphiphilic compound on rotifers. - Doklady Biological Sciences. 2003 (May). Vol. 390. 252-255, https://www.researchgate.net/file.FileLoader.html?key=def6575c794b111fcc31275e853c2b15; [ISSN 0012-4966 (Print) 1608-3105 (Online)]. Welfare of the biosphere depends on filter-feeders that contribute to making water clean and transparent. Important new facts on the hazard of man-made damage to the beneficial function of rotifers, which are the plankton filter-feeders, were discovered. Paper was published, in which for the first time, it was found that a chemical pollutant inhibits filtration activity of rotifers. As a chemical pollutant, a representative of synthetic surfactants was studied. The study featured an advanced technique that allows precise measurement of the filtration rate on the basis of measuring the rate of removal of algal cells from water by rotifers. The experiment was run in the following system: the two-species culture of rotifers (Brachionus calyciflorus) and algae (Nannochloropsis limnetica; Eustigmatophyceae) was studied in a two-stage turbidostat (temperature 20 °C) as described by Walz et al. (1997) with some modifications. Dilution rate (the higher the filtration activity of rotifers, the higher the dilution rate) was monitored in the turbidostat. As a model of a chemical pollutant, the cationic surfactant tetradecyltrimethylammonium bromide (TDTMA) was added to the water of the turbidostat. On the basis of previous studies (Ostroumov, 2000), the concentration of TDTMA was 0.5 mg/L. Dynamics of the dilution rate before and after addition of the chemical was monitored. The dilution rate decreased after the addition of TDTMA. Also, a comparison of the dilution rate in the experimental turbidostat (with the surfactant) with the control turbidostat (without the chemical) was made. Under conditions of the addition of TDTMA the dilution rate was lower than in the control turbidostat. The lower dilution rate means a lower filtration and grazing activity of the population of the rotifers. The results are in accord with the hypothesis that the cationic surfactant TDTMA can inhibit the filtering activity of populations of rotifers. The results support the conclusions of previous publications, in which analogous effects of surfactants on another major group of filter-feeders (the bottom-dwelling bivalve mollusks) were discovered (Doklady of the Russian Academy of Sciences, 2001, 380, pp. 847-849; 2002, vol. 382, pp.138-141). www.springerlink.com/index/R3126462K122M13T.pdf; DOI10.1023/A:1024417903077; Key issues: cationic amphiphilic substance, rotifers Brachionus calyciflorus, algae Nannochloropsis limnetica, turbidostat, filtration activity, cationic surfactant tetradecyltrimethylammonium bromide TDTMA, grazing activity, filtering activity of populations, filter-feeders, chemical pollution, effects of pollutants, sublethal concentration, trophic interactions, man-made effects, anthropogenic,
2003 (May). Vol. 390. 252-255

http://scipeople.ru/publication/66669/; S. A. Ostroumov. Basics of the Molecular-Ecological Mechanism of Water Quality Formation and Water Self-Purification. - Contemporary Problems of Ecology, 2008, Vol. 1, No. 1, pp. 147–152. DOI: 10.1134/S1995425508010177 [ISSN 1995-4255, Pleiades Publishing, Ltd.] Key words: modern ecological theory, polyfunctional role, biota, mechanism, water quality, self-purification, aquatic ecosystems, freshwater, marine, sources of energy, structural and functional units, processes, major taxa, reliability, external factors, man-made impact, anthropogenic, pollution, pollutants, biodiversity protection, filter-feeders, bivalves, xenobiotics, organic and inorganic pollutants, synthetic surfactants, detergents, heavy metals, sustainable use, water and biological resources, ecosystem health, ecosystem services, best management Abstract.—The paper formulates basics of a new modern ecological theory of the polyfunctional role of biota in the molecular-ecological mechanism of water quality formation and water self-purification in aquatic ecosystems. The theory covers the following items: (1) sources of energy for self-purification mechanisms, (2) the main structural and functional units of the water self-purification biomachinery, (3) the main processes involved, (4) contributions of major taxa (groups of organisms) to self-purification, (5) system reliability, (6) the response of the system as a whole to external factors (esp. chemical pollution by xenobiotics including both organic and inorganic pollutants), (7) particulars of the operation of water purification mechanisms, and (8) conclusions and recommendations for biodiversity protection practice, and for sustainable use of water and biological resources. The theory was supported by new author’s experiments and recent publications.
Basics of the Molecular-Ecological Mechanism of Water Quality Formation and Water Self-Purification. - Contemporary Problems of Ecology, 2008, Vol. 1, No. 1, pp. 147–152.