Laboratory for Radiophysical and Optical Methods of Environmental Research, National Research Tomsk State University, Tomsk, Russia.
Center for Biotesting of Nanotechnologies and Nanomaterials Safety, National Research Tomsk State University, Tomsk, Russia.
Environ Monit Assess. 2023 Mar 23;195(4):503. doi: 10.1007/s10661-023-11102-2.
Our previous studies showed that the change in the plankton response to light could be an indicator of environmental pollution. This study experimentally reveals that the response of Daphnia magna Straus and Daphnia pulex plankton ensembles to photostimulation depends on the intensity of the attracting light. This makes it difficult to identify the occurrence and change of pollutant concentration. The large variability in the magnitude of the behavioral response is caused by the nonlinear response of plankton ensembles to the intensity of the attractor stimulus. As the intensity of the photostimulation increases, the variability of the phototropic response passes through increase, decrease, and relative stabilization phases. The paper proposes a modification of the photostimulation method-paired photostimulation involving successive exposure to two photostimuli of increasing intensity. The first stimulus stabilizes the behavioral response, while the increase in response to the second stimulus makes it possible to more accurately assess the responsiveness of the plankton ensemble. The paper studies the sensitivity of the method of paired stimulation of the behavioral response of different types of freshwater plankton ensembles: Daphnia magna Straus, Daphnia pulex to the effects of pollutants (potassium bichromate, microplastic). The study demonstrates good reliability and increased sensitivity of this method of detecting changes in environmental toxicity compared to single photostimulation or traditional bioindication through the survival rate of test organisms.
我们之前的研究表明，浮游生物对光的反应变化可能是环境污染的一个指标。本研究通过实验表明，大型溞（Daphnia magna Straus）和水蚤（Daphnia pulex）浮游生物群体对光刺激的反应取决于吸引光的强度。这使得难以识别污染物浓度的发生和变化。行为反应幅度的大变化是由浮游生物群体对吸引刺激强度的非线性反应引起的。随着光刺激强度的增加，趋光反应的可变性依次经过增加、减少和相对稳定阶段。本文提出了一种光刺激方法的改进——成对光刺激，涉及连续暴露于两个强度递增的光刺激。第一个刺激稳定了行为反应，而对第二个刺激的反应增加使得更准确地评估浮游生物群体的反应性成为可能。本文研究了成对刺激不同类型淡水浮游生物群体（大型溞、水蚤）行为反应方法的敏感性：对污染物（重铬酸钾、微塑料）的影响。与单一光刺激或通过测试生物的存活率进行传统生物指示相比，该研究表明，与单一光刺激或传统生物指示相比，这种检测环境毒性变化的方法具有良好的可靠性和更高的灵敏度。
