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The increasing occurrence of cyanobacterial blooms in water bodies is a serious threat to the environment. Efficient in-lake treatment methods for the control of cyanobacteria proliferation are needed, their in-vivo detection to obtain a real-time response to their presence, as well as the information about their physiological state after the applied treatment. In-vivo fluorescence measurements of photosynthetic pigments have proved to be effective for quantitative and qualitative detection of phytoplankton in a water environment. In the experiment, chlorophyll and phycocyanin fluorescence sensors were used concurrently to detect stress caused by electrochemical oxidation applying an electrolytic cell equipped with borondoped diamond electrodes on a laboratory culture of cyanobacteria Microcystis aeruginosa PCC 7806. The inflicted injuries were reflected in a clear transient increase in the phycocyanin fluorescence signal (for 104 %± 43%) 24 h after the treatment, which was not the case for the chlorophyll fluorescence signal. In the next 72 h of observation, the fluorescence signals decreased (on 40% of the starting signal) indicating a reduction of cell number, which was confirmed by cell count (24% reduction of the starting concentration) and analysis of extracted chlorophyll and phycocyanin pigment. These results demonstrate the viability of the combined application of two sensors as a useful tool for in-vivo detection of induced stress, providing real-time information needed for the evaluation of the efficiency of the in-lake treatment and decision upon the necessity of its repetition. The electrochemical treatment also resulted in a lower free microcystins concentration compared to control. [ABSTRACT FROM AUTHOR]

Purpose: Changes in the behavior of earthworms (for example avoidance of a particular substrate) can influence the soil ecosystem. Our aim was to determine whether the earthworms Eisenia fetida and Lumbricus terrestris are able to avoid ivermectin (a veterinary endectocide belonging to the avermectins). A standard avoidance test with earthworms was conducted using standardized Lufa 2.3 soil (Speyer, Germany) and sandy soil provided by Cinkarna Celje (Slovenia). Materials and methods: A two-chamber system of avoidance test as described in ISO guideline 17512-1 (ISO ) was applied. We investigated the substrate preference of E. fetida and L. terrestris after 48 h at ivermectin concentrations of 8, 32, 64, and 256 mg kg dry soil. Results and discussion: No deterrent effects were observed for either species and either soil types. E. fetida in Lufa 2.3 soil was clearly attracted to ivermectin. More than 70% of the earthworms preferred soil with ivermectin concentrations of 8, 64, and 256 mg kg. No observed effect concentration and lowest observed effect concentration, 2-day exposure, for effects on the avoidance of both species are >256 mg kg dry soil in two different soils. Conclusions: High percentage of earthworms in the test soil was observed in the experiment with E. fetida in Lufa 2.3 soil treated with 8, 64, and 256 mg ivermectin kg. We can conclude that earthworms, as it was observed in E. fetida in Lufa 2.3 soil treated with ivermectin, may be attracted by some chemicals. The percentage of L. terrestris in soil from Cinkarna Celje treated with ivermectin ranged from 39% to 52% and of E. fetida from 33% to 55%. [ABSTRACT FROM AUTHOR]