Библиографическое описание:Флуоресценция хлорофилла в оценке воздействия соединений тяжёлых металлов на водные организмы : научное издание / Г. А. Сорокина [и др.]. - Текст : непосредственный // Известия Иркутского государственного университета. Серия: Биология. Экология. - 2021. - Т. 36, № . - С. 24-36. - ISSN 2073-3372, DOI 10.26516/2073-3372.2021.36.24.
Аннотация:Рассматриваются возможности повышения качества биотестирования состояния среды водных объектов с помощью измерения флуоресценции хлорофилла, позволяющего оперативно получать информацию о физиологических изменениях в организме водных растений и животных. С использованием различных вариаций метода регистрации флуоресценции хлорофилла в серии экспериментов выполнена оценка чувствительности ряда тест-объектов (водоросли, высшие водные растения, ракообразные) к воздействию ионов тяжёлых металлов. Обсуждаются выявленные преимущества метода.
Fluorescent methods allow to improve the bioassays because of time effectiveness. These methods give information on chlorophyll concentration and plant photosynthetic apparatus activity in a short period of time. The aim of this study was to estimate the sensitivity of aquatic organisms to heavy metals using chlorophyll fluorescent methods. The test-organisms of different taxonomic categories were used, including thermophilic strain <i>Chlorella vulgaris</i> Beijer, aquatic plants <i>Elodea сanadensis</i> Michx. and <i>Lemna minor</i> L., crustacean <i>Daphnia magna</i> Straus. Fluorimeter “Foton 10” developed in SibFU was employed to measure prompt and delayed fluorescence (PF and DF respectively). The experiments revealed that copper ions affected DF of chlorella in 30 minutes, resulting in a 50% decrease of relative indicator of DF (RIDF) in the range of concentrations 0.005-0.01 mg/l of Cu<sup>2+</sup>. Measuring the DF of duckweed was less time-consuming compared to registration the changing of morphological parameters when the plants were exposed to heavy metals. Copper, cadmium, and nickel exposures were found to decrease the RIDF of duckweed by more than 50% at the concentrations of 0.17, 0.31, and 1.89 mg/l respectively. However, zinc had no significant effect on the RIDF of <i>Lemna minor</i> in the range of 0.1-8 mg/l of Zn<sup>2+</sup> within 24 h of exposure time. The analysis of fluorescent parameters of Canadian elodea showed the possibility of using the plant as a sorbent during the bioremediation of aquatic environments from heavy metals. Registration of chlorophyll fluorescence allowed revealing the toxic effects of negligible concentrations of heavy metals in experiments with the feeding rate of daphnids. The median effective concentrations (EC<sub>50</sub>) were 0.002, 0.02, 0.4, and 0.25 mg/l of Cd<sup>2+</sup>, Cu<sup>2+</sup>, Zn<sup>2+</sup>, and potassium dichromate respectively. This makes it possible to obtain information on the effects of pollution in the early stages of exposure and in a shorter time. Thus, the use of chlorophyll fluorescence in biomonitoring the state of the aquatic environment makes it possible to more quickly respond to changes in the ecological situation in water bodies.
